text: /**
   * pugixml parser - version 1.8
   * --------------------------------------------------------
   * Copyright (C) 2006-2018, by Arseny Kapoulkine (arseny.kapoulkine@gmail.com)
   * Report bugs and download new versions at http://pugixml.org/
   *
   * This library is distributed under the MIT License. See notice at the end
   * of this file.
   *
   * This work is based on the pugxml parser, which is:
   * Copyright (C) 2003, by Kristen Wegner (kristen@tima.net)
   */
  
  #ifndef SOURCE_PUGIXML_CPP
  #define SOURCE_PUGIXML_CPP
  
  #include "pugixml.hpp"
  
  #include <stdlib.h>
  #include <stdio.h>
  #include <string.h>
  #include <assert.h>
  #include <limits.h>
  
  #ifdef PUGIXML_WCHAR_MODE
  #	include <wchar.h>
  #endif
  
  #ifndef PUGIXML_NO_XPATH
  #	include <math.h>
  #	include <float.h>
  #endif
  
  #ifndef PUGIXML_NO_STL
  #	include <istream>
  #	include <ostream>
  #	include <string>
  #endif
  
  // For placement new
  #include <new>
  
  #ifdef _MSC_VER
  #	pragma warning(push)
  #	pragma warning(disable: 4127) // conditional expression is constant
  #	pragma warning(disable: 4324) // structure was padded due to __declspec(align())
  #	pragma warning(disable: 4702) // unreachable code
  #	pragma warning(disable: 4996) // this function or variable may be unsafe
  #endif
  
  #if defined(_MSC_VER) && defined(__c2__)
  #	pragma clang diagnostic push
  #	pragma clang diagnostic ignored "-Wdeprecated" // this function or variable may be unsafe
  #endif
  
  #ifdef __INTEL_COMPILER
  #	pragma warning(disable: 177) // function was declared but never referenced
  #	pragma warning(disable: 279) // controlling expression is constant
  #	pragma warning(disable: 1478 1786) // function was declared "deprecated"
  #	pragma warning(disable: 1684) // conversion from pointer to same-sized integral type
  #endif
  
  #if defined(__BORLANDC__) && defined(PUGIXML_HEADER_ONLY)
  #	pragma warn -8080 // symbol is declared but never used; disabling this inside push/pop bracket does not make the warning go away
  #endif
  
  #ifdef __BORLANDC__
  #	pragma option push
  #	pragma warn -8008 // condition is always false
  #	pragma warn -8066 // unreachable code
  #endif
  
  #ifdef __SNC__
  // Using diag_push/diag_pop does not disable the warnings inside templates due to a compiler bug
  #	pragma diag_suppress=178 // function was declared but never referenced
  #	pragma diag_suppress=237 // controlling expression is constant
  #endif
  
  // Inlining controls
  #if defined(_MSC_VER) && _MSC_VER >= 1300
  #	define PUGI__NO_INLINE __declspec(noinline)
  #elif defined(__GNUC__)
  #	define PUGI__NO_INLINE __attribute__((noinline))
  #else
  #	define PUGI__NO_INLINE
  #endif
  
  // Branch weight controls
  #if defined(__GNUC__) && !defined(__c2__)
  #	define PUGI__UNLIKELY(cond) __builtin_expect(cond, 0)
  #else
  #	define PUGI__UNLIKELY(cond) (cond)
  #endif
  
  // Simple static assertion
  #define PUGI__STATIC_ASSERT(cond) { static const char condition_failed[(cond) ? 1 : -1] = {0}; (void)condition_failed[0]; }
  
  // Digital Mars C++ bug workaround for passing char loaded from memory via stack
  #ifdef __DMC__
  #	define PUGI__DMC_VOLATILE volatile
  #else
  #	define PUGI__DMC_VOLATILE
  #endif
  
  // Integer sanitizer workaround
  #ifdef __has_attribute
  #	if __has_attribute(no_sanitize)
  #		define PUGI__UNSIGNED_OVERFLOW __attribute__((no_sanitize("unsigned-integer-overflow")))
  #	else
  #		define PUGI__UNSIGNED_OVERFLOW
  #	endif
  #else
  #	define PUGI__UNSIGNED_OVERFLOW
  #endif
  
  // Borland C++ bug workaround for not defining ::memcpy depending on header include order (can't always use std::memcpy because some compilers don't have it at all)
  #if defined(__BORLANDC__) && !defined(__MEM_H_USING_LIST)
  using std::memcpy;
  using std::memmove;
  using std::memset;
  #endif
  
  // Some MinGW versions have headers that erroneously omit LLONG_MIN/LLONG_MAX/ULLONG_MAX definitions in strict ANSI mode
  #if defined(PUGIXML_HAS_LONG_LONG) && defined(__MINGW32__) && defined(__STRICT_ANSI__) && !defined(LLONG_MAX) && !defined(LLONG_MIN) && !defined(ULLONG_MAX)
  #	define LLONG_MAX 9223372036854775807LL
  #	define LLONG_MIN (-LLONG_MAX-1)
  #	define ULLONG_MAX (2ULL*LLONG_MAX+1)
  #endif
  
  // In some environments MSVC is a compiler but the CRT lacks certain MSVC-specific features
  #if defined(_MSC_VER) && !defined(__S3E__)
  #	define PUGI__MSVC_CRT_VERSION _MSC_VER
  #endif
  
  // Not all platforms have snprintf; we define a wrapper that uses snprintf if possible. This only works with buffers with a known size.
  #if __cplusplus >= 201103
  #	define PUGI__SNPRINTF(buf, ...) snprintf(buf, sizeof(buf), __VA_ARGS__)
  #elif defined(PUGI__MSVC_CRT_VERSION) && PUGI__MSVC_CRT_VERSION >= 1400
  #	define PUGI__SNPRINTF(buf, ...) _snprintf_s(buf, _countof(buf), _TRUNCATE, __VA_ARGS__)
  #else
  #	define PUGI__SNPRINTF sprintf
  #endif
  
  // We put implementation details into an anonymous namespace in source mode, but have to keep it in non-anonymous namespace in header-only mode to prevent binary bloat.
  #ifdef PUGIXML_HEADER_ONLY
  #	define PUGI__NS_BEGIN namespace pugi { namespace impl {
  #	define PUGI__NS_END } }
  #	define PUGI__FN inline
  #	define PUGI__FN_NO_INLINE inline
  #else
  #	if defined(_MSC_VER) && _MSC_VER < 1300 // MSVC6 seems to have an amusing bug with anonymous namespaces inside namespaces
  #		define PUGI__NS_BEGIN namespace pugi { namespace impl {
  #		define PUGI__NS_END } }
  #	else
  #		define PUGI__NS_BEGIN namespace pugi { namespace impl { namespace {
  #		define PUGI__NS_END } } }
  #	endif
  #	define PUGI__FN
  #	define PUGI__FN_NO_INLINE PUGI__NO_INLINE
  #endif
  
  // uintptr_t
  #if (defined(_MSC_VER) && _MSC_VER < 1600) || (defined(__BORLANDC__) && __BORLANDC__ < 0x561)
  namespace pugi
  {
  #	ifndef _UINTPTR_T_DEFINED
  	typedef size_t uintptr_t;
  #	endif
  
  	typedef unsigned __int8 uint8_t;
  	typedef unsigned __int16 uint16_t;
  	typedef unsigned __int32 uint32_t;
  }
  #else
  #	include <stdint.h>
  #endif
  
  // Memory allocation
  PUGI__NS_BEGIN
  	PUGI__FN void* default_allocate(size_t size)
  	{
  		return malloc(size);
  	}
  
  	PUGI__FN void default_deallocate(void* ptr)
  	{
  		free(ptr);
  	}
  
  	template <typename T>
  	struct xml_memory_management_function_storage
  	{
  		static allocation_function allocate;
  		static deallocation_function deallocate;
  	};
  
  	// Global allocation functions are stored in class statics so that in header mode linker deduplicates them
  	// Without a template<> we'll get multiple definitions of the same static
  	template <typename T> allocation_function xml_memory_management_function_storage<T>::allocate = default_allocate;
  	template <typename T> deallocation_function xml_memory_management_function_storage<T>::deallocate = default_deallocate;
  
  	typedef xml_memory_management_function_storage<int> xml_memory;
  PUGI__NS_END
  
  // String utilities
  PUGI__NS_BEGIN
  	// Get string length
  	PUGI__FN size_t strlength(const char_t* s)
  	{
  		assert(s);
  
  	#ifdef PUGIXML_WCHAR_MODE
  		return wcslen(s);
  	#else
  		return strlen(s);
  	#endif
  	}
  
  	// Compare two strings
  	PUGI__FN bool strequal(const char_t* src, const char_t* dst)
  	{
  		assert(src && dst);
  
  	#ifdef PUGIXML_WCHAR_MODE
  		return wcscmp(src, dst) == 0;
  	#else
  		return strcmp(src, dst) == 0;
  	#endif
  	}
  
  	// Compare lhs with [rhs_begin, rhs_end)
  	PUGI__FN bool strequalrange(const char_t* lhs, const char_t* rhs, size_t count)
  	{
  		for (size_t i = 0; i < count; ++i)
  			if (lhs[i] != rhs[i])
  				return false;
  
  		return lhs[count] == 0;
  	}
  
  	// Get length of wide string, even if CRT lacks wide character support
  	PUGI__FN size_t strlength_wide(const wchar_t* s)
  	{
  		assert(s);
  
  	#ifdef PUGIXML_WCHAR_MODE
  		return wcslen(s);
  	#else
  		const wchar_t* end = s;
  		while (*end) end++;
  		return static_cast<size_t>(end - s);
  	#endif
  	}
  PUGI__NS_END
  
  // auto_ptr-like object for exception recovery
  PUGI__NS_BEGIN
  	template <typename T> struct auto_deleter
  	{
  		typedef void (*D)(T*);
  
  		T* data;
  		D deleter;
  
  		auto_deleter(T* data_, D deleter_): data(data_), deleter(deleter_)
  		{
  		}
  
  		~auto_deleter()
  		{
  			if (data) deleter(data);
  		}
  
  		T* release()
  		{
  			T* result = data;
  			data = 0;
  			return result;
  		}
  	};
  PUGI__NS_END
  
  #ifdef PUGIXML_COMPACT
  PUGI__NS_BEGIN
  	class compact_hash_table
  	{
  	public:
  		compact_hash_table(): _items(0), _capacity(0), _count(0)
  		{
  		}
  
  		void clear()
  		{
  			if (_items)
  			{
  				xml_memory::deallocate(_items);
  				_items = 0;
  				_capacity = 0;
  				_count = 0;
  			}
  		}
  
  		void* find(const void* key)
  		{
  			if (_capacity == 0) return 0;
  
  			item_t* item = get_item(key);
  			assert(item);
  			assert(item->key == key || (item->key == 0 && item->value == 0));
  
  			return item->value;
  		}
  
  		void insert(const void* key, void* value)
  		{
  			assert(_capacity != 0 && _count < _capacity - _capacity / 4);
  
  			item_t* item = get_item(key);
  			assert(item);
  
  			if (item->key == 0)
  			{
  				_count++;
  				item->key = key;
  			}
  
  			item->value = value;
  		}
  
  		bool reserve(size_t extra = 16)
  		{
  			if (_count + extra >= _capacity - _capacity / 4)
  				return rehash(_count + extra);
  
  			return true;
  		}
  
  	private:
  		struct item_t
  		{
  			const void* key;
  			void* value;
  		};
  
  		item_t* _items;
  		size_t _capacity;
  
  		size_t _count;
  
  		bool rehash(size_t count);
  
  		item_t* get_item(const void* key)
  		{
  			assert(key);
  			assert(_capacity > 0);
  
  			size_t hashmod = _capacity - 1;
  			size_t bucket = hash(key) & hashmod;
  
  			for (size_t probe = 0; probe <= hashmod; ++probe)
  			{
  				item_t& probe_item = _items[bucket];
  
  				if (probe_item.key == key || probe_item.key == 0)
  					return &probe_item;
  
  				// hash collision, quadratic probing
  				bucket = (bucket + probe + 1) & hashmod;
  			}
  
  			assert(false && "Hash table is full"); // unreachable
  			return 0;
  		}
  
  		static PUGI__UNSIGNED_OVERFLOW unsigned int hash(const void* key)
  		{
  			unsigned int h = static_cast<unsigned int>(reinterpret_cast<uintptr_t>(key));
  
  			// MurmurHash3 32-bit finalizer
  			h ^= h >> 16;
  			h *= 0x85ebca6bu;
  			h ^= h >> 13;
  			h *= 0xc2b2ae35u;
  			h ^= h >> 16;
  
  			return h;
  		}
  	};
  
  	PUGI__FN_NO_INLINE bool compact_hash_table::rehash(size_t count)
  	{
  		size_t capacity = 32;
  		while (count >= capacity - capacity / 4)
  			capacity *= 2;
  
  		compact_hash_table rt;
  		rt._capacity = capacity;
  		rt._items = static_cast<item_t*>(xml_memory::allocate(sizeof(item_t) * capacity));
  
  		if (!rt._items)
  			return false;
  
  		memset(rt._items, 0, sizeof(item_t) * capacity);
  
  		for (size_t i = 0; i < _capacity; ++i)
  			if (_items[i].key)
  				rt.insert(_items[i].key, _items[i].value);
  
  		if (_items)
  			xml_memory::deallocate(_items);
  
  		_capacity = capacity;
  		_items = rt._items;
  
  		assert(_count == rt._count);
  
  		return true;
  	}
  
  PUGI__NS_END
  #endif
  
  PUGI__NS_BEGIN
  #ifdef PUGIXML_COMPACT
  	static const uintptr_t xml_memory_block_alignment = 4;
  #else
  	static const uintptr_t xml_memory_block_alignment = sizeof(void*);
  #endif
  
  	// extra metadata bits
  	static const uintptr_t xml_memory_page_contents_shared_mask = 64;
  	static const uintptr_t xml_memory_page_name_allocated_mask = 32;
  	static const uintptr_t xml_memory_page_value_allocated_mask = 16;
  	static const uintptr_t xml_memory_page_type_mask = 15;
  
  	// combined masks for string uniqueness
  	static const uintptr_t xml_memory_page_name_allocated_or_shared_mask = xml_memory_page_name_allocated_mask | xml_memory_page_contents_shared_mask;
  	static const uintptr_t xml_memory_page_value_allocated_or_shared_mask = xml_memory_page_value_allocated_mask | xml_memory_page_contents_shared_mask;
  
  #ifdef PUGIXML_COMPACT
  	#define PUGI__GETHEADER_IMPL(object, page, flags) // unused
  	#define PUGI__GETPAGE_IMPL(header) (header).get_page()
  #else
  	#define PUGI__GETHEADER_IMPL(object, page, flags) (((reinterpret_cast<char*>(object) - reinterpret_cast<char*>(page)) << 8) | (flags))
  	// this macro casts pointers through void* to avoid 'cast increases required alignment of target type' warnings
  	#define PUGI__GETPAGE_IMPL(header) static_cast<impl::xml_memory_page*>(const_cast<void*>(static_cast<const void*>(reinterpret_cast<const char*>(&header) - (header >> 8))))
  #endif
  
  	#define PUGI__GETPAGE(n) PUGI__GETPAGE_IMPL((n)->header)
  	#define PUGI__NODETYPE(n) static_cast<xml_node_type>((n)->header & impl::xml_memory_page_type_mask)
  
  	struct xml_allocator;
  
  	struct xml_memory_page
  	{
  		static xml_memory_page* construct(void* memory)
  		{
  			xml_memory_page* result = static_cast<xml_memory_page*>(memory);
  
  			result->allocator = 0;
  			result->prev = 0;
  			result->next = 0;
  			result->busy_size = 0;
  			result->freed_size = 0;
  
  		#ifdef PUGIXML_COMPACT
  			result->compact_string_base = 0;
  			result->compact_shared_parent = 0;
  			result->compact_page_marker = 0;
  		#endif
  
  			return result;
  		}
  
  		xml_allocator* allocator;
  
  		xml_memory_page* prev;
  		xml_memory_page* next;
  
  		size_t busy_size;
  		size_t freed_size;
  
  	#ifdef PUGIXML_COMPACT
  		char_t* compact_string_base;
  		void* compact_shared_parent;
  		uint32_t* compact_page_marker;
  	#endif
  	};
  
  	static const size_t xml_memory_page_size =
  	#ifdef PUGIXML_MEMORY_PAGE_SIZE
  		(PUGIXML_MEMORY_PAGE_SIZE)
  	#else
  		32768
  	#endif
  		- sizeof(xml_memory_page);
  
  	struct xml_memory_string_header
  	{
  		uint16_t page_offset; // offset from page->data
  		uint16_t full_size; // 0 if string occupies whole page
  	};
  
  	struct xml_allocator
  	{
  		xml_allocator(xml_memory_page* root): _root(root), _busy_size(root->busy_size)
  		{
  		#ifdef PUGIXML_COMPACT
  			_hash = 0;
  		#endif
  		}
  
  		xml_memory_page* allocate_page(size_t data_size)
  		{
  			size_t size = sizeof(xml_memory_page) + data_size;
  
  			// allocate block with some alignment, leaving memory for worst-case padding
  			void* memory = xml_memory::allocate(size);
  			if (!memory) return 0;
  
  			// prepare page structure
  			xml_memory_page* page = xml_memory_page::construct(memory);
  			assert(page);
  
  			page->allocator = _root->allocator;
  
  			return page;
  		}
  
  		static void deallocate_page(xml_memory_page* page)
  		{
  			xml_memory::deallocate(page);
  		}
  
  		void* allocate_memory_oob(size_t size, xml_memory_page*& out_page);
  
  		void* allocate_memory(size_t size, xml_memory_page*& out_page)
  		{
  			if (PUGI__UNLIKELY(_busy_size + size > xml_memory_page_size))
  				return allocate_memory_oob(size, out_page);
  
  			void* buf = reinterpret_cast<char*>(_root) + sizeof(xml_memory_page) + _busy_size;
  
  			_busy_size += size;
  
  			out_page = _root;
  
  			return buf;
  		}
  
  	#ifdef PUGIXML_COMPACT
  		void* allocate_object(size_t size, xml_memory_page*& out_page)
  		{
  			void* result = allocate_memory(size + sizeof(uint32_t), out_page);
  			if (!result) return 0;
  
  			// adjust for marker
  			ptrdiff_t offset = static_cast<char*>(result) - reinterpret_cast<char*>(out_page->compact_page_marker);
  
  			if (PUGI__UNLIKELY(static_cast<uintptr_t>(offset) >= 256 * xml_memory_block_alignment))
  			{
  				// insert new marker
  				uint32_t* marker = static_cast<uint32_t*>(result);
  
  				*marker = static_cast<uint32_t>(reinterpret_cast<char*>(marker) - reinterpret_cast<char*>(out_page));
  				out_page->compact_page_marker = marker;
  
  				// since we don't reuse the page space until we reallocate it, we can just pretend that we freed the marker block
  				// this will make sure deallocate_memory correctly tracks the size
  				out_page->freed_size += sizeof(uint32_t);
  
  				return marker + 1;
  			}
  			else
  			{
  				// roll back uint32_t part
  				_busy_size -= sizeof(uint32_t);
  
  				return result;
  			}
  		}
  	#else
  		void* allocate_object(size_t size, xml_memory_page*& out_page)
  		{
  			return allocate_memory(size, out_page);
  		}
  	#endif
  
  		void deallocate_memory(void* ptr, size_t size, xml_memory_page* page)
  		{
  			if (page == _root) page->busy_size = _busy_size;
  
  			assert(ptr >= reinterpret_cast<char*>(page) + sizeof(xml_memory_page) && ptr < reinterpret_cast<char*>(page) + sizeof(xml_memory_page) + page->busy_size);
  			(void)!ptr;
  
  			page->freed_size += size;
  			assert(page->freed_size <= page->busy_size);
  
  			if (page->freed_size == page->busy_size)
  			{
  				if (page->next == 0)
  				{
  					assert(_root == page);
  
  					// top page freed, just reset sizes
  					page->busy_size = 0;
  					page->freed_size = 0;
  
  				#ifdef PUGIXML_COMPACT
  					// reset compact state to maximize efficiency
  					page->compact_string_base = 0;
  					page->compact_shared_parent = 0;
  					page->compact_page_marker = 0;
  				#endif
  
  					_busy_size = 0;
  				}
  				else
  				{
  					assert(_root != page);
  					assert(page->prev);
  
  					// remove from the list
  					page->prev->next = page->next;
  					page->next->prev = page->prev;
  
  					// deallocate
  					deallocate_page(page);
  				}
  			}
  		}
  
  		char_t* allocate_string(size_t length)
  		{
  			static const size_t max_encoded_offset = (1 << 16) * xml_memory_block_alignment;
  
  			PUGI__STATIC_ASSERT(xml_memory_page_size <= max_encoded_offset);
  
  			// allocate memory for string and header block
  			size_t size = sizeof(xml_memory_string_header) + length * sizeof(char_t);
  
  			// round size up to block alignment boundary
  			size_t full_size = (size + (xml_memory_block_alignment - 1)) & ~(xml_memory_block_alignment - 1);
  
  			xml_memory_page* page;
  			xml_memory_string_header* header = static_cast<xml_memory_string_header*>(allocate_memory(full_size, page));
  
  			if (!header) return 0;
  
  			// setup header
  			ptrdiff_t page_offset = reinterpret_cast<char*>(header) - reinterpret_cast<char*>(page) - sizeof(xml_memory_page);
  
  			assert(page_offset % xml_memory_block_alignment == 0);
  			assert(page_offset >= 0 && static_cast<size_t>(page_offset) < max_encoded_offset);
  			header->page_offset = static_cast<uint16_t>(static_cast<size_t>(page_offset) / xml_memory_block_alignment);
  
  			// full_size == 0 for large strings that occupy the whole page
  			assert(full_size % xml_memory_block_alignment == 0);
  			assert(full_size < max_encoded_offset || (page->busy_size == full_size && page_offset == 0));
  			header->full_size = static_cast<uint16_t>(full_size < max_encoded_offset ? full_size / xml_memory_block_alignment : 0);
  
  			// round-trip through void* to avoid 'cast increases required alignment of target type' warning
  			// header is guaranteed a pointer-sized alignment, which should be enough for char_t
  			return static_cast<char_t*>(static_cast<void*>(header + 1));
  		}
  
  		void deallocate_string(char_t* string)
  		{
  			// this function casts pointers through void* to avoid 'cast increases required alignment of target type' warnings
  			// we're guaranteed the proper (pointer-sized) alignment on the input string if it was allocated via allocate_string
  
  			// get header
  			xml_memory_string_header* header = static_cast<xml_memory_string_header*>(static_cast<void*>(string)) - 1;
  			assert(header);
  
  			// deallocate
  			size_t page_offset = sizeof(xml_memory_page) + header->page_offset * xml_memory_block_alignment;
  			xml_memory_page* page = reinterpret_cast<xml_memory_page*>(static_cast<void*>(reinterpret_cast<char*>(header) - page_offset));
  
  			// if full_size == 0 then this string occupies the whole page
  			size_t full_size = header->full_size == 0 ? page->busy_size : header->full_size * xml_memory_block_alignment;
  
  			deallocate_memory(header, full_size, page);
  		}
  
  		bool reserve()
  		{
  		#ifdef PUGIXML_COMPACT
  			return _hash->reserve();
  		#else
  			return true;
  		#endif
  		}
  
  		xml_memory_page* _root;
  		size_t _busy_size;
  
  	#ifdef PUGIXML_COMPACT
  		compact_hash_table* _hash;
  	#endif
  	};
  
  	PUGI__FN_NO_INLINE void* xml_allocator::allocate_memory_oob(size_t size, xml_memory_page*& out_page)
  	{
  		const size_t large_allocation_threshold = xml_memory_page_size / 4;
  
  		xml_memory_page* page = allocate_page(size <= large_allocation_threshold ? xml_memory_page_size : size);
  		out_page = page;
  
  		if (!page) return 0;
  
  		if (size <= large_allocation_threshold)
  		{
  			_root->busy_size = _busy_size;
  
  			// insert page at the end of linked list
  			page->prev = _root;
  			_root->next = page;
  			_root = page;
  
  			_busy_size = size;
  		}
  		else
  		{
  			// insert page before the end of linked list, so that it is deleted as soon as possible
  			// the last page is not deleted even if it's empty (see deallocate_memory)
  			assert(_root->prev);
  
  			page->prev = _root->prev;
  			page->next = _root;
  
  			_root->prev->next = page;
  			_root->prev = page;
  
  			page->busy_size = size;
  		}
  
  		return reinterpret_cast<char*>(page) + sizeof(xml_memory_page);
  	}
  PUGI__NS_END
  
  #ifdef PUGIXML_COMPACT
  PUGI__NS_BEGIN
  	static const uintptr_t compact_alignment_log2 = 2;
  	static const uintptr_t compact_alignment = 1 << compact_alignment_log2;
  
  	class compact_header
  	{
  	public:
  		compact_header(xml_memory_page* page, unsigned int flags)
  		{
  			PUGI__STATIC_ASSERT(xml_memory_block_alignment == compact_alignment);
  
  			ptrdiff_t offset = (reinterpret_cast<char*>(this) - reinterpret_cast<char*>(page->compact_page_marker));
  			assert(offset % compact_alignment == 0 && static_cast<uintptr_t>(offset) < 256 * compact_alignment);
  
  			_page = static_cast<unsigned char>(offset >> compact_alignment_log2);
  			_flags = static_cast<unsigned char>(flags);
  		}
  
  		void operator&=(uintptr_t mod)
  		{
  			_flags &= static_cast<unsigned char>(mod);
  		}
  
  		void operator|=(uintptr_t mod)
  		{
  			_flags |= static_cast<unsigned char>(mod);
  		}
  
  		uintptr_t operator&(uintptr_t mod) const
  		{
  			return _flags & mod;
  		}
  
  		xml_memory_page* get_page() const
  		{
  			// round-trip through void* to silence 'cast increases required alignment of target type' warnings
  			const char* page_marker = reinterpret_cast<const char*>(this) - (_page << compact_alignment_log2);
  			const char* page = page_marker - *reinterpret_cast<const uint32_t*>(static_cast<const void*>(page_marker));
  
  			return const_cast<xml_memory_page*>(reinterpret_cast<const xml_memory_page*>(static_cast<const void*>(page)));
  		}
  
  	private:
  		unsigned char _page;
  		unsigned char _flags;
  	};
  
  	PUGI__FN xml_memory_page* compact_get_page(const void* object, int header_offset)
  	{
  		const compact_header* header = reinterpret_cast<const compact_header*>(static_cast<const char*>(object) - header_offset);
  
  		return header->get_page();
  	}
  
  	template <int header_offset, typename T> PUGI__FN_NO_INLINE T* compact_get_value(const void* object)
  	{
  		return static_cast<T*>(compact_get_page(object, header_offset)->allocator->_hash->find(object));
  	}
  
  	template <int header_offset, typename T> PUGI__FN_NO_INLINE void compact_set_value(const void* object, T* value)
  	{
  		compact_get_page(object, header_offset)->allocator->_hash->insert(object, value);
  	}
  
  	template <typename T, int header_offset, int start = -126> class compact_pointer
  	{
  	public:
  		compact_pointer(): _data(0)
  		{
  		}
  
  		void operator=(const compact_pointer& rhs)
  		{
  			*this = rhs + 0;
  		}
  
  		void operator=(T* value)
  		{
  			if (value)
  			{
  				// value is guaranteed to be compact-aligned; 'this' is not
  				// our decoding is based on 'this' aligned to compact alignment downwards (see operator T*)
  				// so for negative offsets (e.g. -3) we need to adjust the diff by compact_alignment - 1 to
  				// compensate for arithmetic shift rounding for negative values
  				ptrdiff_t diff = reinterpret_cast<char*>(value) - reinterpret_cast<char*>(this);
  				ptrdiff_t offset = ((diff + int(compact_alignment - 1)) >> compact_alignment_log2) - start;
  
  				if (static_cast<uintptr_t>(offset) <= 253)
  					_data = static_cast<unsigned char>(offset + 1);
  				else
  				{
  					compact_set_value<header_offset>(this, value);
  
  					_data = 255;
  				}
  			}
  			else
  				_data = 0;
  		}
  
  		operator T*() const
  		{
  			if (_data)
  			{
  				if (_data < 255)
  				{
  					uintptr_t base = reinterpret_cast<uintptr_t>(this) & ~(compact_alignment - 1);
  
  					return reinterpret_cast<T*>(base + ((_data - 1 + start) << compact_alignment_log2));
  				}
  				else
  					return compact_get_value<header_offset, T>(this);
  			}
  			else
  				return 0;
  		}
  
  		T* operator->() const
  		{
  			return *this;
  		}
  
  	private:
  		unsigned char _data;
  	};
  
  	template <typename T, int header_offset> class compact_pointer_parent
  	{
  	public:
  		compact_pointer_parent(): _data(0)
  		{
  		}
  
  		void operator=(const compact_pointer_parent& rhs)
  		{
  			*this = rhs + 0;
  		}
  
  		void operator=(T* value)
  		{
  			if (value)
  			{
  				// value is guaranteed to be compact-aligned; 'this' is not
  				// our decoding is based on 'this' aligned to compact alignment downwards (see operator T*)
  				// so for negative offsets (e.g. -3) we need to adjust the diff by compact_alignment - 1 to
  				// compensate for arithmetic shift behavior for negative values
  				ptrdiff_t diff = reinterpret_cast<char*>(value) - reinterpret_cast<char*>(this);
  				ptrdiff_t offset = ((diff + int(compact_alignment - 1)) >> compact_alignment_log2) + 65533;
  
  				if (static_cast<uintptr_t>(offset) <= 65533)
  				{
  					_data = static_cast<unsigned short>(offset + 1);
  				}
  				else
  				{
  					xml_memory_page* page = compact_get_page(this, header_offset);
  
  					if (PUGI__UNLIKELY(page->compact_shared_parent == 0))
  						page->compact_shared_parent = value;
  
  					if (page->compact_shared_parent == value)
  					{
  						_data = 65534;
  					}
  					else
  					{
  						compact_set_value<header_offset>(this, value);
  
  						_data = 65535;
  					}
  				}
  			}
  			else
  			{
  				_data = 0;
  			}
  		}
  
  		operator T*() const
  		{
  			if (_data)
  			{
  				if (_data < 65534)
  				{
  					uintptr_t base = reinterpret_cast<uintptr_t>(this) & ~(compact_alignment - 1);
  
  					return reinterpret_cast<T*>(base + ((_data - 1 - 65533) << compact_alignment_log2));
  				}
  				else if (_data == 65534)
  					return static_cast<T*>(compact_get_page(this, header_offset)->compact_shared_parent);
  				else
  					return compact_get_value<header_offset, T>(this);
  			}
  			else
  				return 0;
  		}
  
  		T* operator->() const
  		{
  			return *this;
  		}
  
  	private:
  		uint16_t _data;
  	};
  
  	template <int header_offset, int base_offset> class compact_string
  	{
  	public:
  		compact_string(): _data(0)
  		{
  		}
  
  		void operator=(const compact_string& rhs)
  		{
  			*this = rhs + 0;
  		}
  
  		void operator=(char_t* value)
  		{
  			if (value)
  			{
  				xml_memory_page* page = compact_get_page(this, header_offset);
  
  				if (PUGI__UNLIKELY(page->compact_string_base == 0))
  					page->compact_string_base = value;
  
  				ptrdiff_t offset = value - page->compact_string_base;
  
  				if (static_cast<uintptr_t>(offset) < (65535 << 7))
  				{
  					// round-trip through void* to silence 'cast increases required alignment of target type' warnings
  					uint16_t* base = reinterpret_cast<uint16_t*>(static_cast<void*>(reinterpret_cast<char*>(this) - base_offset));
  
  					if (*base == 0)
  					{
  						*base = static_cast<uint16_t>((offset >> 7) + 1);
  						_data = static_cast<unsigned char>((offset & 127) + 1);
  					}
  					else
  					{
  						ptrdiff_t remainder = offset - ((*base - 1) << 7);
  
  						if (static_cast<uintptr_t>(remainder) <= 253)
  						{
  							_data = static_cast<unsigned char>(remainder + 1);
  						}
  						else
  						{
  							compact_set_value<header_offset>(this, value);
  
  							_data = 255;
  						}
  					}
  				}
  				else
  				{
  					compact_set_value<header_offset>(this, value);
  
  					_data = 255;
  				}
  			}
  			else
  			{
  				_data = 0;
  			}
  		}
  
  		operator char_t*() const
  		{
  			if (_data)
  			{
  				if (_data < 255)
  				{
  					xml_memory_page* page = compact_get_page(this, header_offset);
  
  					// round-trip through void* to silence 'cast increases required alignment of target type' warnings
  					const uint16_t* base = reinterpret_cast<const uint16_t*>(static_cast<const void*>(reinterpret_cast<const char*>(this) - base_offset));
  					assert(*base);
  
  					ptrdiff_t offset = ((*base - 1) << 7) + (_data - 1);
  
  					return page->compact_string_base + offset;
  				}
  				else
  				{
  					return compact_get_value<header_offset, char_t>(this);
  				}
  			}
  			else
  				return 0;
  		}
  
  	private:
  		unsigned char _data;
  	};
  PUGI__NS_END
  #endif
  
  #ifdef PUGIXML_COMPACT
  namespace pugi
  {
  	struct xml_attribute_struct
  	{
  		xml_attribute_struct(impl::xml_memory_page* page): header(page, 0), namevalue_base(0)
  		{
  			PUGI__STATIC_ASSERT(sizeof(xml_attribute_struct) == 8);
  		}
  
  		impl::compact_header header;
  
  		uint16_t namevalue_base;
  
  		impl::compact_string<4, 2> name;
  		impl::compact_string<5, 3> value;
  
  		impl::compact_pointer<xml_attribute_struct, 6> prev_attribute_c;
  		impl::compact_pointer<xml_attribute_struct, 7, 0> next_attribute;
  	};
  
  	struct xml_node_struct
  	{
  		xml_node_struct(impl::xml_memory_page* page, xml_node_type type): header(page, type), namevalue_base(0)
  		{
  			PUGI__STATIC_ASSERT(sizeof(xml_node_struct) == 12);
  		}
  
  		impl::compact_header header;
  
  		uint16_t namevalue_base;
  
  		impl::compact_string<4, 2> name;
  		impl::compact_string<5, 3> value;
  
  		impl::compact_pointer_parent<xml_node_struct, 6> parent;
  
  		impl::compact_pointer<xml_node_struct, 8, 0> first_child;
  
  		impl::compact_pointer<xml_node_struct,  9>    prev_sibling_c;
  		impl::compact_pointer<xml_node_struct, 10, 0> next_sibling;
  
  		impl::compact_pointer<xml_attribute_struct, 11, 0> first_attribute;
  	};
  }
  #else
  namespace pugi
  {
  	struct xml_attribute_struct
  	{
  		xml_attribute_struct(impl::xml_memory_page* page): name(0), value(0), prev_attribute_c(0), next_attribute(0)
  		{
  			header = PUGI__GETHEADER_IMPL(this, page, 0);
  		}
  
  		uintptr_t header;
  
  		char_t*	name;
  		char_t*	value;
  
  		xml_attribute_struct* prev_attribute_c;
  		xml_attribute_struct* next_attribute;
  	};
  
  	struct xml_node_struct
  	{
  		xml_node_struct(impl::xml_memory_page* page, xml_node_type type): name(0), value(0), parent(0), first_child(0), prev_sibling_c(0), next_sibling(0), first_attribute(0)
  		{
  			header = PUGI__GETHEADER_IMPL(this, page, type);
  		}
  
  		uintptr_t header;
  
  		char_t* name;
  		char_t* value;
  
  		xml_node_struct* parent;
  
  		xml_node_struct* first_child;
  
  		xml_node_struct* prev_sibling_c;
  		xml_node_struct* next_sibling;
  
  		xml_attribute_struct* first_attribute;
  	};
  }
  #endif
  
  PUGI__NS_BEGIN
  	struct xml_extra_buffer
  	{
  		char_t* buffer;
  		xml_extra_buffer* next;
  	};
  
  	struct xml_document_struct: public xml_node_struct, public xml_allocator
  	{
  		xml_document_struct(xml_memory_page* page): xml_node_struct(page, node_document), xml_allocator(page), buffer(0), extra_buffers(0)
  		{
  		}
  
  		const char_t* buffer;
  
  		xml_extra_buffer* extra_buffers;
  
  	#ifdef PUGIXML_COMPACT
  		compact_hash_table hash;
  	#endif
  	};
  
  	template <typename Object> inline xml_allocator& get_allocator(const Object* object)
  	{
  		assert(object);
  
  		return *PUGI__GETPAGE(object)->allocator;
  	}
  
  	template <typename Object> inline xml_document_struct& get_document(const Object* object)
  	{
  		assert(object);
  
  		return *static_cast<xml_document_struct*>(PUGI__GETPAGE(object)->allocator);
  	}
  PUGI__NS_END
  
  // Low-level DOM operations
  PUGI__NS_BEGIN
  	inline xml_attribute_struct* allocate_attribute(xml_allocator& alloc)
  	{
  		xml_memory_page* page;
  		void* memory = alloc.allocate_object(sizeof(xml_attribute_struct), page);
  		if (!memory) return 0;
  
  		return new (memory) xml_attribute_struct(page);
  	}
  
  	inline xml_node_struct* allocate_node(xml_allocator& alloc, xml_node_type type)
  	{
  		xml_memory_page* page;
  		void* memory = alloc.allocate_object(sizeof(xml_node_struct), page);
  		if (!memory) return 0;
  
  		return new (memory) xml_node_struct(page, type);
  	}
  
  	inline void destroy_attribute(xml_attribute_struct* a, xml_allocator& alloc)
  	{
  		if (a->header & impl::xml_memory_page_name_allocated_mask)
  			alloc.deallocate_string(a->name);
  
  		if (a->header & impl::xml_memory_page_value_allocated_mask)
  			alloc.deallocate_string(a->value);
  
  		alloc.deallocate_memory(a, sizeof(xml_attribute_struct), PUGI__GETPAGE(a));
  	}
  
  	inline void destroy_node(xml_node_struct* n, xml_allocator& alloc)
  	{
  		if (n->header & impl::xml_memory_page_name_allocated_mask)
  			alloc.deallocate_string(n->name);
  
  		if (n->header & impl::xml_memory_page_value_allocated_mask)
  			alloc.deallocate_string(n->value);
  
  		for (xml_attribute_struct* attr = n->first_attribute; attr; )
  		{
  			xml_attribute_struct* next = attr->next_attribute;
  
  			destroy_attribute(attr, alloc);
  
  			attr = next;
  		}
  
  		for (xml_node_struct* child = n->first_child; child; )
  		{
  			xml_node_struct* next = child->next_sibling;
  
  			destroy_node(child, alloc);
  
  			child = next;
  		}
  
  		alloc.deallocate_memory(n, sizeof(xml_node_struct), PUGI__GETPAGE(n));
  	}
  
  	inline void append_node(xml_node_struct* child, xml_node_struct* node)
  	{
  		child->parent = node;
  
  		xml_node_struct* head = node->first_child;
  
  		if (head)
  		{
  			xml_node_struct* tail = head->prev_sibling_c;
  
  			tail->next_sibling = child;
  			child->prev_sibling_c = tail;
  			head->prev_sibling_c = child;
  		}
  		else
  		{
  			node->first_child = child;
  			child->prev_sibling_c = child;
  		}
  	}
  
  	inline void prepend_node(xml_node_struct* child, xml_node_struct* node)
  	{
  		child->parent = node;
  
  		xml_node_struct* head = node->first_child;
  
  		if (head)
  		{
  			child->prev_sibling_c = head->prev_sibling_c;
  			head->prev_sibling_c = child;
  		}
  		else
  			child->prev_sibling_c = child;
  
  		child->next_sibling = head;
  		node->first_child = child;
  	}
  
  	inline void insert_node_after(xml_node_struct* child, xml_node_struct* node)
  	{
  		xml_node_struct* parent = node->parent;
  
  		child->parent = parent;
  
  		if (node->next_sibling)
  			node->next_sibling->prev_sibling_c = child;
  		else
  			parent->first_child->prev_sibling_c = child;
  
  		child->next_sibling = node->next_sibling;
  		child->prev_sibling_c = node;
  
  		node->next_sibling = child;
  	}
  
  	inline void insert_node_before(xml_node_struct* child, xml_node_struct* node)
  	{
  		xml_node_struct* parent = node->parent;
  
  		child->parent = parent;
  
  		if (node->prev_sibling_c->next_sibling)
  			node->prev_sibling_c->next_sibling = child;
  		else
  			parent->first_child = child;
  
  		child->prev_sibling_c = node->prev_sibling_c;
  		child->next_sibling = node;
  
  		node->prev_sibling_c = child;
  	}
  
  	inline void remove_node(xml_node_struct* node)
  	{
  		xml_node_struct* parent = node->parent;
  
  		if (node->next_sibling)
  			node->next_sibling->prev_sibling_c = node->prev_sibling_c;
  		else
  			parent->first_child->prev_sibling_c = node->prev_sibling_c;
  
  		if (node->prev_sibling_c->next_sibling)
  			node->prev_sibling_c->next_sibling = node->next_sibling;
  		else
  			parent->first_child = node->next_sibling;
  
  		node->parent = 0;
  		node->prev_sibling_c = 0;
  		node->next_sibling = 0;
  	}
  
  	inline void append_attribute(xml_attribute_struct* attr, xml_node_struct* node)
  	{
  		xml_attribute_struct* head = node->first_attribute;
  
  		if (head)
  		{
  			xml_attribute_struct* tail = head->prev_attribute_c;
  
  			tail->next_attribute = attr;
  			attr->prev_attribute_c = tail;
  			head->prev_attribute_c = attr;
  		}
  		else
  		{
  			node->first_attribute = attr;
  			attr->prev_attribute_c = attr;
  		}
  	}
  
  	inline void prepend_attribute(xml_attribute_struct* attr, xml_node_struct* node)
  	{
  		xml_attribute_struct* head = node->first_attribute;
  
  		if (head)
  		{
  			attr->prev_attribute_c = head->prev_attribute_c;
  			head->prev_attribute_c = attr;
  		}
  		else
  			attr->prev_attribute_c = attr;
  
  		attr->next_attribute = head;
  		node->first_attribute = attr;
  	}
  
  	inline void insert_attribute_after(xml_attribute_struct* attr, xml_attribute_struct* place, xml_node_struct* node)
  	{
  		if (place->next_attribute)
  			place->next_attribute->prev_attribute_c = attr;
  		else
  			node->first_attribute->prev_attribute_c = attr;
  
  		attr->next_attribute = place->next_attribute;
  		attr->prev_attribute_c = place;
  		place->next_attribute = attr;
  	}
  
  	inline void insert_attribute_before(xml_attribute_struct* attr, xml_attribute_struct* place, xml_node_struct* node)
  	{
  		if (place->prev_attribute_c->next_attribute)
  			place->prev_attribute_c->next_attribute = attr;
  		else
  			node->first_attribute = attr;
  
  		attr->prev_attribute_c = place->prev_attribute_c;
  		attr->next_attribute = place;
  		place->prev_attribute_c = attr;
  	}
  
  	inline void remove_attribute(xml_attribute_struct* attr, xml_node_struct* node)
  	{
  		if (attr->next_attribute)
  			attr->next_attribute->prev_attribute_c = attr->prev_attribute_c;
  		else
  			node->first_attribute->prev_attribute_c = attr->prev_attribute_c;
  
  		if (attr->prev_attribute_c->next_attribute)
  			attr->prev_attribute_c->next_attribute = attr->next_attribute;
  		else
  			node->first_attribute = attr->next_attribute;
  
  		attr->prev_attribute_c = 0;
  		attr->next_attribute = 0;
  	}
  
  	PUGI__FN_NO_INLINE xml_node_struct* append_new_node(xml_node_struct* node, xml_allocator& alloc, xml_node_type type = node_element)
  	{
  		if (!alloc.reserve()) return 0;
  
  		xml_node_struct* child = allocate_node(alloc, type);
  		if (!child) return 0;
  
  		append_node(child, node);
  
  		return child;
  	}
  
  	PUGI__FN_NO_INLINE xml_attribute_struct* append_new_attribute(xml_node_struct* node, xml_allocator& alloc)
  	{
  		if (!alloc.reserve()) return 0;
  
  		xml_attribute_struct* attr = allocate_attribute(alloc);
  		if (!attr) return 0;
  
  		append_attribute(attr, node);
  
  		return attr;
  	}
  PUGI__NS_END
  
  // Helper classes for code generation
  PUGI__NS_BEGIN
  	struct opt_false
  	{
  		enum { value = 0 };
  	};
  
  	struct opt_true
  	{
  		enum { value = 1 };
  	};
  PUGI__NS_END
  
  // Unicode utilities
  PUGI__NS_BEGIN
  	inline uint16_t endian_swap(uint16_t value)
  	{
  		return static_cast<uint16_t>(((value & 0xff) << 8) | (value >> 8));
  	}
  
  	inline uint32_t endian_swap(uint32_t value)
  	{
  		return ((value & 0xff) << 24) | ((value & 0xff00) << 8) | ((value & 0xff0000) >> 8) | (value >> 24);
  	}
  
  	struct utf8_counter
  	{
  		typedef size_t value_type;
  
  		static value_type low(value_type result, uint32_t ch)
  		{
  			// U+0000..U+007F
  			if (ch < 0x80) return result + 1;
  			// U+0080..U+07FF
  			else if (ch < 0x800) return result + 2;
  			// U+0800..U+FFFF
  			else return result + 3;
  		}
  
  		static value_type high(value_type result, uint32_t)
  		{
  			// U+10000..U+10FFFF
  			return result + 4;
  		}
  	};
  
  	struct utf8_writer
  	{
  		typedef uint8_t* value_type;
  
  		static value_type low(value_type result, uint32_t ch)
  		{
  			// U+0000..U+007F
  			if (ch < 0x80)
  			{
  				*result = static_cast<uint8_t>(ch);
  				return result + 1;
  			}
  			// U+0080..U+07FF
  			else if (ch < 0x800)
  			{
  				result[0] = static_cast<uint8_t>(0xC0 | (ch >> 6));
  				result[1] = static_cast<uint8_t>(0x80 | (ch & 0x3F));
  				return result + 2;
  			}
  			// U+0800..U+FFFF
  			else
  			{
  				result[0] = static_cast<uint8_t>(0xE0 | (ch >> 12));
  				result[1] = static_cast<uint8_t>(0x80 | ((ch >> 6) & 0x3F));
  				result[2] = static_cast<uint8_t>(0x80 | (ch & 0x3F));
  				return result + 3;
  			}
  		}
  
  		static value_type high(value_type result, uint32_t ch)
  		{
  			// U+10000..U+10FFFF
  			result[0] = static_cast<uint8_t>(0xF0 | (ch >> 18));
  			result[1] = static_cast<uint8_t>(0x80 | ((ch >> 12) & 0x3F));
  			result[2] = static_cast<uint8_t>(0x80 | ((ch >> 6) & 0x3F));
  			result[3] = static_cast<uint8_t>(0x80 | (ch & 0x3F));
  			return result + 4;
  		}
  
  		static value_type any(value_type result, uint32_t ch)
  		{
  			return (ch < 0x10000) ? low(result, ch) : high(result, ch);
  		}
  	};
  
  	struct utf16_counter
  	{
  		typedef size_t value_type;
  
  		static value_type low(value_type result, uint32_t)
  		{
  			return result + 1;
  		}
  
  		static value_type high(value_type result, uint32_t)
  		{
  			return result + 2;
  		}
  	};
  
  	struct utf16_writer
  	{
  		typedef uint16_t* value_type;
  
  		static value_type low(value_type result, uint32_t ch)
  		{
  			*result = static_cast<uint16_t>(ch);
  
  			return result + 1;
  		}
  
  		static value_type high(value_type result, uint32_t ch)
  		{
  			uint32_t msh = static_cast<uint32_t>(ch - 0x10000) >> 10;
  			uint32_t lsh = static_cast<uint32_t>(ch - 0x10000) & 0x3ff;
  
  			result[0] = static_cast<uint16_t>(0xD800 + msh);
  			result[1] = static_cast<uint16_t>(0xDC00 + lsh);
  
  			return result + 2;
  		}
  
  		static value_type any(value_type result, uint32_t ch)
  		{
  			return (ch < 0x10000) ? low(result, ch) : high(result, ch);
  		}
  	};
  
  	struct utf32_counter
  	{
  		typedef size_t value_type;
  
  		static value_type low(value_type result, uint32_t)
  		{
  			return result + 1;
  		}
  
  		static value_type high(value_type result, uint32_t)
  		{
  			return result + 1;
  		}
  	};
  
  	struct utf32_writer
  	{
  		typedef uint32_t* value_type;
  
  		static value_type low(value_type result, uint32_t ch)
  		{
  			*result = ch;
  
  			return result + 1;
  		}
  
  		static value_type high(value_type result, uint32_t ch)
  		{
  			*result = ch;
  
  			return result + 1;
  		}
  
  		static value_type any(value_type result, uint32_t ch)
  		{
  			*result = ch;
  
  			return result + 1;
  		}
  	};
  
  	struct latin1_writer
  	{
  		typedef uint8_t* value_type;
  
  		static value_type low(value_type result, uint32_t ch)
  		{
  			*result = static_cast<uint8_t>(ch > 255 ? '?' : ch);
  
  			return result + 1;
  		}
  
  		static value_type high(value_type result, uint32_t ch)
  		{
  			(void)ch;
  
  			*result = '?';
  
  			return result + 1;
  		}
  	};
  
  	struct utf8_decoder
  	{
  		typedef uint8_t type;
  
  		template <typename Traits> static inline typename Traits::value_type process(const uint8_t* data, size_t size, typename Traits::value_type result, Traits)
  		{
  			const uint8_t utf8_byte_mask = 0x3f;
  
  			while (size)
  			{
  				uint8_t lead = *data;
  
  				// 0xxxxxxx -> U+0000..U+007F
  				if (lead < 0x80)
  				{
  					result = Traits::low(result, lead);
  					data += 1;
  					size -= 1;
  
  					// process aligned single-byte (ascii) blocks
  					if ((reinterpret_cast<uintptr_t>(data) & 3) == 0)
  					{
  						// round-trip through void* to silence 'cast increases required alignment of target type' warnings
  						while (size >= 4 && (*static_cast<const uint32_t*>(static_cast<const void*>(data)) & 0x80808080) == 0)
  						{
  							result = Traits::low(result, data[0]);
  							result = Traits::low(result, data[1]);
  							result = Traits::low(result, data[2]);
  							result = Traits::low(result, data[3]);
  							data += 4;
  							size -= 4;
  						}
  					}
  				}
  				// 110xxxxx -> U+0080..U+07FF
  				else if (static_cast<unsigned int>(lead - 0xC0) < 0x20 && size >= 2 && (data[1] & 0xc0) == 0x80)
  				{
  					result = Traits::low(result, ((lead & ~0xC0) << 6) | (data[1] & utf8_byte_mask));
  					data += 2;
  					size -= 2;
  				}
  				// 1110xxxx -> U+0800-U+FFFF
  				else if (static_cast<unsigned int>(lead - 0xE0) < 0x10 && size >= 3 && (data[1] & 0xc0) == 0x80 && (data[2] & 0xc0) == 0x80)
  				{
  					result = Traits::low(result, ((lead & ~0xE0) << 12) | ((data[1] & utf8_byte_mask) << 6) | (data[2] & utf8_byte_mask));
  					data += 3;
  					size -= 3;
  				}
  				// 11110xxx -> U+10000..U+10FFFF
  				else if (static_cast<unsigned int>(lead - 0xF0) < 0x08 && size >= 4 && (data[1] & 0xc0) == 0x80 && (data[2] & 0xc0) == 0x80 && (data[3] & 0xc0) == 0x80)
  				{
  					result = Traits::high(result, ((lead & ~0xF0) << 18) | ((data[1] & utf8_byte_mask) << 12) | ((data[2] & utf8_byte_mask) << 6) | (data[3] & utf8_byte_mask));
  					data += 4;
  					size -= 4;
  				}
  				// 10xxxxxx or 11111xxx -> invalid
  				else
  				{
  					data += 1;
  					size -= 1;
  				}
  			}
  
  			return result;
  		}
  	};
  
  	template <typename opt_swap> struct utf16_decoder
  	{
  		typedef uint16_t type;
  
  		template <typename Traits> static inline typename Traits::value_type process(const uint16_t* data, size_t size, typename Traits::value_type result, Traits)
  		{
  			while (size)
  			{
  				uint16_t lead = opt_swap::value ? endian_swap(*data) : *data;
  
  				// U+0000..U+D7FF
  				if (lead < 0xD800)
  				{
  					result = Traits::low(result, lead);
  					data += 1;
  					size -= 1;
  				}
  				// U+E000..U+FFFF
  				else if (static_cast<unsigned int>(lead - 0xE000) < 0x2000)
  				{
  					result = Traits::low(result, lead);
  					data += 1;
  					size -= 1;
  				}
  				// surrogate pair lead
  				else if (static_cast<unsigned int>(lead - 0xD800) < 0x400 && size >= 2)
  				{
  					uint16_t next = opt_swap::value ? endian_swap(data[1]) : data[1];
  
  					if (static_cast<unsigned int>(next - 0xDC00) < 0x400)
  					{
  						result = Traits::high(result, 0x10000 + ((lead & 0x3ff) << 10) + (next & 0x3ff));
  						data += 2;
  						size -= 2;
  					}
  					else
  					{
  						data += 1;
  						size -= 1;
  					}
  				}
  				else
  				{
  					data += 1;
  					size -= 1;
  				}
  			}
  
  			return result;
  		}
  	};
  
  	template <typename opt_swap> struct utf32_decoder
  	{
  		typedef uint32_t type;
  
  		template <typename Traits> static inline typename Traits::value_type process(const uint32_t* data, size_t size, typename Traits::value_type result, Traits)
  		{
  			while (size)
  			{
  				uint32_t lead = opt_swap::value ? endian_swap(*data) : *data;
  
  				// U+0000..U+FFFF
  				if (lead < 0x10000)
  				{
  					result = Traits::low(result, lead);
  					data += 1;
  					size -= 1;
  				}
  				// U+10000..U+10FFFF
  				else
  				{
  					result = Traits::high(result, lead);
  					data += 1;
  					size -= 1;
  				}
  			}
  
  			return result;
  		}
  	};
  
  	struct latin1_decoder
  	{
  		typedef uint8_t type;
  
  		template <typename Traits> static inline typename Traits::value_type process(const uint8_t* data, size_t size, typename Traits::value_type result, Traits)
  		{
  			while (size)
  			{
  				result = Traits::low(result, *data);
  				data += 1;
  				size -= 1;
  			}
  
  			return result;
  		}
  	};
  
  	template <size_t size> struct wchar_selector;
  
  	template <> struct wchar_selector<2>
  	{
  		typedef uint16_t type;
  		typedef utf16_counter counter;
  		typedef utf16_writer writer;
  		typedef utf16_decoder<opt_false> decoder;
  	};
  
  	template <> struct wchar_selector<4>
  	{
  		typedef uint32_t type;
  		typedef utf32_counter counter;
  		typedef utf32_writer writer;
  		typedef utf32_decoder<opt_false> decoder;
  	};
  
  	typedef wchar_selector<sizeof(wchar_t)>::counter wchar_counter;
  	typedef wchar_selector<sizeof(wchar_t)>::writer wchar_writer;
  
  	struct wchar_decoder
  	{
  		typedef wchar_t type;
  
  		template <typename Traits> static inline typename Traits::value_type process(const wchar_t* data, size_t size, typename Traits::value_type result, Traits traits)
  		{
  			typedef wchar_selector<sizeof(wchar_t)>::decoder decoder;
  
  			return decoder::process(reinterpret_cast<const typename decoder::type*>(data), size, result, traits);
  		}
  	};
  
  #ifdef PUGIXML_WCHAR_MODE
  	PUGI__FN void convert_wchar_endian_swap(wchar_t* result, const wchar_t* data, size_t length)
  	{
  		for (size_t i = 0; i < length; ++i)
  			result[i] = static_cast<wchar_t>(endian_swap(static_cast<wchar_selector<sizeof(wchar_t)>::type>(data[i])));
  	}
  #endif
  PUGI__NS_END
  
  PUGI__NS_BEGIN
  	enum chartype_t
  	{
  		ct_parse_pcdata = 1,	// \0, &, \r, <
  		ct_parse_attr = 2,		// \0, &, \r, ', "
  		ct_parse_attr_ws = 4,	// \0, &, \r, ', ", \n, tab
  		ct_space = 8,			// \r, \n, space, tab
  		ct_parse_cdata = 16,	// \0, ], >, \r
  		ct_parse_comment = 32,	// \0, -, >, \r
  		ct_symbol = 64,			// Any symbol > 127, a-z, A-Z, 0-9, _, :, -, .
  		ct_start_symbol = 128	// Any symbol > 127, a-z, A-Z, _, :
  	};
  
  	static const unsigned char chartype_table[256] =
  	{
  		55,  0,   0,   0,   0,   0,   0,   0,      0,   12,  12,  0,   0,   63,  0,   0,   // 0-15
  		0,   0,   0,   0,   0,   0,   0,   0,      0,   0,   0,   0,   0,   0,   0,   0,   // 16-31
  		8,   0,   6,   0,   0,   0,   7,   6,      0,   0,   0,   0,   0,   96,  64,  0,   // 32-47
  		64,  64,  64,  64,  64,  64,  64,  64,     64,  64,  192, 0,   1,   0,   48,  0,   // 48-63
  		0,   192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192, // 64-79
  		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 0,   0,   16,  0,   192, // 80-95
  		0,   192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192, // 96-111
  		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 0, 0, 0, 0, 0,           // 112-127
  
  		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192, // 128+
  		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192,
  		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192,
  		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192,
  		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192,
  		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192,
  		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192,
  		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192
  	};
  
  	enum chartypex_t
  	{
  		ctx_special_pcdata = 1,   // Any symbol >= 0 and < 32 (except \t, \r, \n), &, <, >
  		ctx_special_attr = 2,     // Any symbol >= 0 and < 32 (except \t), &, <, >, "
  		ctx_start_symbol = 4,	  // Any symbol > 127, a-z, A-Z, _
  		ctx_digit = 8,			  // 0-9
  		ctx_symbol = 16			  // Any symbol > 127, a-z, A-Z, 0-9, _, -, .
  	};
  
  	static const unsigned char chartypex_table[256] =
  	{
  		3,  3,  3,  3,  3,  3,  3,  3,     3,  0,  2,  3,  3,  2,  3,  3,     // 0-15
  		3,  3,  3,  3,  3,  3,  3,  3,     3,  3,  3,  3,  3,  3,  3,  3,     // 16-31
  		0,  0,  2,  0,  0,  0,  3,  0,     0,  0,  0,  0,  0, 16, 16,  0,     // 32-47
  		24, 24, 24, 24, 24, 24, 24, 24,    24, 24, 0,  0,  3,  0,  3,  0,     // 48-63
  
  		0,  20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,    // 64-79
  		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 0,  0,  0,  0,  20,    // 80-95
  		0,  20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,    // 96-111
  		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 0,  0,  0,  0,  0,     // 112-127
  
  		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,    // 128+
  		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,
  		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,
  		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,
  		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,
  		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,
  		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,
  		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20
  	};
  
  #ifdef PUGIXML_WCHAR_MODE
  	#define PUGI__IS_CHARTYPE_IMPL(c, ct, table) ((static_cast<unsigned int>(c) < 128 ? table[static_cast<unsigned int>(c)] : table[128]) & (ct))
  #else
  	#define PUGI__IS_CHARTYPE_IMPL(c, ct, table) (table[static_cast<unsigned char>(c)] & (ct))
  #endif
  
  	#define PUGI__IS_CHARTYPE(c, ct) PUGI__IS_CHARTYPE_IMPL(c, ct, chartype_table)
  	#define PUGI__IS_CHARTYPEX(c, ct) PUGI__IS_CHARTYPE_IMPL(c, ct, chartypex_table)
  
  	PUGI__FN bool is_little_endian()
  	{
  		unsigned int ui = 1;
  
  		return *reinterpret_cast<unsigned char*>(&ui) == 1;
  	}
  
  	PUGI__FN xml_encoding get_wchar_encoding()
  	{
  		PUGI__STATIC_ASSERT(sizeof(wchar_t) == 2 || sizeof(wchar_t) == 4);
  
  		if (sizeof(wchar_t) == 2)
  			return is_little_endian() ? encoding_utf16_le : encoding_utf16_be;
  		else
  			return is_little_endian() ? encoding_utf32_le : encoding_utf32_be;
  	}
  
  	PUGI__FN bool parse_declaration_encoding(const uint8_t* data, size_t size, const uint8_t*& out_encoding, size_t& out_length)
  	{
  	#define PUGI__SCANCHAR(ch) { if (offset >= size || data[offset] != ch) return false; offset++; }
  	#define PUGI__SCANCHARTYPE(ct) { while (offset < size && PUGI__IS_CHARTYPE(data[offset], ct)) offset++; }
  
  		// check if we have a non-empty XML declaration
  		if (size < 6 || !((data[0] == '<') & (data[1] == '?') & (data[2] == 'x') & (data[3] == 'm') & (data[4] == 'l') && PUGI__IS_CHARTYPE(data[5], ct_space)))
  			return false;
  
  		// scan XML declaration until the encoding field
  		for (size_t i = 6; i + 1 < size; ++i)
  		{
  			// declaration can not contain ? in quoted values
  			if (data[i] == '?')
  				return false;
  
  			if (data[i] == 'e' && data[i + 1] == 'n')
  			{
  				size_t offset = i;
  
  				// encoding follows the version field which can't contain 'en' so this has to be the encoding if XML is well formed
  				PUGI__SCANCHAR('e'); PUGI__SCANCHAR('n'); PUGI__SCANCHAR('c'); PUGI__SCANCHAR('o');
  				PUGI__SCANCHAR('d'); PUGI__SCANCHAR('i'); PUGI__SCANCHAR('n'); PUGI__SCANCHAR('g');
  
  				// S? = S?
  				PUGI__SCANCHARTYPE(ct_space);
  				PUGI__SCANCHAR('=');
  				PUGI__SCANCHARTYPE(ct_space);
  
  				// the only two valid delimiters are ' and "
  				uint8_t delimiter = (offset < size && data[offset] == '"') ? '"' : '\'';
  
  				PUGI__SCANCHAR(delimiter);
  
  				size_t start = offset;
  
  				out_encoding = data + offset;
  
  				PUGI__SCANCHARTYPE(ct_symbol);
  
  				out_length = offset - start;
  
  				PUGI__SCANCHAR(delimiter);
  
  				return true;
  			}
  		}
  
  		return false;
  
  	#undef PUGI__SCANCHAR
  	#undef PUGI__SCANCHARTYPE
  	}
  
  	PUGI__FN xml_encoding guess_buffer_encoding(const uint8_t* data, size_t size)
  	{
  		// skip encoding autodetection if input buffer is too small
  		if (size < 4) return encoding_utf8;
  
  		uint8_t d0 = data[0], d1 = data[1], d2 = data[2], d3 = data[3];
  
  		// look for BOM in first few bytes
  		if (d0 == 0 && d1 == 0 && d2 == 0xfe && d3 == 0xff) return encoding_utf32_be;
  		if (d0 == 0xff && d1 == 0xfe && d2 == 0 && d3 == 0) return encoding_utf32_le;
  		if (d0 == 0xfe && d1 == 0xff) return encoding_utf16_be;
  		if (d0 == 0xff && d1 == 0xfe) return encoding_utf16_le;
  		if (d0 == 0xef && d1 == 0xbb && d2 == 0xbf) return encoding_utf8;
  
  		// look for <, <? or <?xm in various encodings
  		if (d0 == 0 && d1 == 0 && d2 == 0 && d3 == 0x3c) return encoding_utf32_be;
  		if (d0 == 0x3c && d1 == 0 && d2 == 0 && d3 == 0) return encoding_utf32_le;
  		if (d0 == 0 && d1 == 0x3c && d2 == 0 && d3 == 0x3f) return encoding_utf16_be;
  		if (d0 == 0x3c && d1 == 0 && d2 == 0x3f && d3 == 0) return encoding_utf16_le;
  
  		// look for utf16 < followed by node name (this may fail, but is better than utf8 since it's zero terminated so early)
  		if (d0 == 0 && d1 == 0x3c) return encoding_utf16_be;
  		if (d0 == 0x3c && d1 == 0) return encoding_utf16_le;
  
  		// no known BOM detected; parse declaration
  		const uint8_t* enc = 0;
  		size_t enc_length = 0;
  
  		if (d0 == 0x3c && d1 == 0x3f && d2 == 0x78 && d3 == 0x6d && parse_declaration_encoding(data, size, enc, enc_length))
  		{
  			// iso-8859-1 (case-insensitive)
  			if (enc_length == 10
  				&& (enc[0] | ' ') == 'i' && (enc[1] | ' ') == 's' && (enc[2] | ' ') == 'o'
  				&& enc[3] == '-' && enc[4] == '8' && enc[5] == '8' && enc[6] == '5' && enc[7] == '9'
  				&& enc[8] == '-' && enc[9] == '1')
  				return encoding_latin1;
  
  			// latin1 (case-insensitive)
  			if (enc_length == 6
  				&& (enc[0] | ' ') == 'l' && (enc[1] | ' ') == 'a' && (enc[2] | ' ') == 't'
  				&& (enc[3] | ' ') == 'i' && (enc[4] | ' ') == 'n'
  				&& enc[5] == '1')
  				return encoding_latin1;
  		}
  
  		return encoding_utf8;
  	}
  
  	PUGI__FN xml_encoding get_buffer_encoding(xml_encoding encoding, const void* contents, size_t size)
  	{
  		// replace wchar encoding with utf implementation
  		if (encoding == encoding_wchar) return get_wchar_encoding();
  
  		// replace utf16 encoding with utf16 with specific endianness
  		if (encoding == encoding_utf16) return is_little_endian() ? encoding_utf16_le : encoding_utf16_be;
  
  		// replace utf32 encoding with utf32 with specific endianness
  		if (encoding == encoding_utf32) return is_little_endian() ? encoding_utf32_le : encoding_utf32_be;
  
  		// only do autodetection if no explicit encoding is requested
  		if (encoding != encoding_auto) return encoding;
  
  		// try to guess encoding (based on XML specification, Appendix F.1)
  		const uint8_t* data = static_cast<const uint8_t*>(contents);
  
  		return guess_buffer_encoding(data, size);
  	}
  
  	PUGI__FN bool get_mutable_buffer(char_t*& out_buffer, size_t& out_length, const void* contents, size_t size, bool is_mutable)
  	{
  		size_t length = size / sizeof(char_t);
  
  		if (is_mutable)
  		{
  			out_buffer = static_cast<char_t*>(const_cast<void*>(contents));
  			out_length = length;
  		}
  		else
  		{
  			char_t* buffer = static_cast<char_t*>(xml_memory::allocate((length + 1) * sizeof(char_t)));
  			if (!buffer) return false;
  
  			if (contents)
  				memcpy(buffer, contents, length * sizeof(char_t));
  			else
  				assert(length == 0);
  
  			buffer[length] = 0;
  
  			out_buffer = buffer;
  			out_length = length + 1;
  		}
  
  		return true;
  	}
  
  #ifdef PUGIXML_WCHAR_MODE
  	PUGI__FN bool need_endian_swap_utf(xml_encoding le, xml_encoding re)
  	{
  		return (le == encoding_utf16_be && re == encoding_utf16_le) || (le == encoding_utf16_le && re == encoding_utf16_be) ||
  			   (le == encoding_utf32_be && re == encoding_utf32_le) || (le == encoding_utf32_le && re == encoding_utf32_be);
  	}
  
  	PUGI__FN bool convert_buffer_endian_swap(char_t*& out_buffer, size_t& out_length, const void* contents, size_t size, bool is_mutable)
  	{
  		const char_t* data = static_cast<const char_t*>(contents);
  		size_t length = size / sizeof(char_t);
  
  		if (is_mutable)
  		{
  			char_t* buffer = const_cast<char_t*>(data);
  
  			convert_wchar_endian_swap(buffer, data, length);
  
  			out_buffer = buffer;
  			out_length = length;
  		}
  		else
  		{
  			char_t* buffer = static_cast<char_t*>(xml_memory::allocate((length + 1) * sizeof(char_t)));
  			if (!buffer) return false;
  
  			convert_wchar_endian_swap(buffer, data, length);
  			buffer[length] = 0;
  
  			out_buffer = buffer;
  			out_length = length + 1;
  		}
  
  		return true;
  	}
  
  	template <typename D> PUGI__FN bool convert_buffer_generic(char_t*& out_buffer, size_t& out_length, const void* contents, size_t size, D)
  	{
  		const typename D::type* data = static_cast<const typename D::type*>(contents);
  		size_t data_length = size / sizeof(typename D::type);
  
  		// first pass: get length in wchar_t units
  		size_t length = D::process(data, data_length, 0, wchar_counter());
  
  		// allocate buffer of suitable length
  		char_t* buffer = static_cast<char_t*>(xml_memory::allocate((length + 1) * sizeof(char_t)));
  		if (!buffer) return false;
  
  		// second pass: convert utf16 input to wchar_t
  		wchar_writer::value_type obegin = reinterpret_cast<wchar_writer::value_type>(buffer);
  		wchar_writer::value_type oend = D::process(data, data_length, obegin, wchar_writer());
  
  		assert(oend == obegin + length);
  		*oend = 0;
  
  		out_buffer = buffer;
  		out_length = length + 1;
  
  		return true;
  	}
  
  	PUGI__FN bool convert_buffer(char_t*& out_buffer, size_t& out_length, xml_encoding encoding, const void* contents, size_t size, bool is_mutable)
  	{
  		// get native encoding
  		xml_encoding wchar_encoding = get_wchar_encoding();
  
  		// fast path: no conversion required
  		if (encoding == wchar_encoding)
  			return get_mutable_buffer(out_buffer, out_length, contents, size, is_mutable);
  
  		// only endian-swapping is required
  		if (need_endian_swap_utf(encoding, wchar_encoding))
  			return convert_buffer_endian_swap(out_buffer, out_length, contents, size, is_mutable);
  
  		// source encoding is utf8
  		if (encoding == encoding_utf8)
  			return convert_buffer_generic(out_buffer, out_length, contents, size, utf8_decoder());
  
  		// source encoding is utf16
  		if (encoding == encoding_utf16_be || encoding == encoding_utf16_le)
  		{
  			xml_encoding native_encoding = is_little_endian() ? encoding_utf16_le : encoding_utf16_be;
  
  			return (native_encoding == encoding) ?
  				convert_buffer_generic(out_buffer, out_length, contents, size, utf16_decoder<opt_false>()) :
  				convert_buffer_generic(out_buffer, out_length, contents, size, utf16_decoder<opt_true>());
  		}
  
  		// source encoding is utf32
  		if (encoding == encoding_utf32_be || encoding == encoding_utf32_le)
  		{
  			xml_encoding native_encoding = is_little_endian() ? encoding_utf32_le : encoding_utf32_be;
  
  			return (native_encoding == encoding) ?
  				convert_buffer_generic(out_buffer, out_length, contents, size, utf32_decoder<opt_false>()) :
  				convert_buffer_generic(out_buffer, out_length, contents, size, utf32_decoder<opt_true>());
  		}
  
  		// source encoding is latin1
  		if (encoding == encoding_latin1)
  			return convert_buffer_generic(out_buffer, out_length, contents, size, latin1_decoder());
  
  		assert(false && "Invalid encoding"); // unreachable
  		return false;
  	}
  #else
  	template <typename D> PUGI__FN bool convert_buffer_generic(char_t*& out_buffer, size_t& out_length, const void* contents, size_t size, D)
  	{
  		const typename D::type* data = static_cast<const typename D::type*>(contents);
  		size_t data_length = size / sizeof(typename D::type);
  
  		// first pass: get length in utf8 units
  		size_t length = D::process(data, data_length, 0, utf8_counter());
  
  		// allocate buffer of suitable length
  		char_t* buffer = static_cast<char_t*>(xml_memory::allocate((length + 1) * sizeof(char_t)));
  		if (!buffer) return false;
  
  		// second pass: convert utf16 input to utf8
  		uint8_t* obegin = reinterpret_cast<uint8_t*>(buffer);
  		uint8_t* oend = D::process(data, data_length, obegin, utf8_writer());
  
  		assert(oend == obegin + length);
  		*oend = 0;
  
  		out_buffer = buffer;
  		out_length = length + 1;
  
  		return true;
  	}
  
  	PUGI__FN size_t get_latin1_7bit_prefix_length(const uint8_t* data, size_t size)
  	{
  		for (size_t i = 0; i < size; ++i)
  			if (data[i] > 127)
  				return i;
  
  		return size;
  	}
  
  	PUGI__FN bool convert_buffer_latin1(char_t*& out_buffer, size_t& out_length, const void* contents, size_t size, bool is_mutable)
  	{
  		const uint8_t* data = static_cast<const uint8_t*>(contents);
  		size_t data_length = size;
  
  		// get size of prefix that does not need utf8 conversion
  		size_t prefix_length = get_latin1_7bit_prefix_length(data, data_length);
  		assert(prefix_length <= data_length);
  
  		const uint8_t* postfix = data + prefix_length;
  		size_t postfix_length = data_length - prefix_length;
  
  		// if no conversion is needed, just return the original buffer
  		if (postfix_length == 0) return get_mutable_buffer(out_buffer, out_length, contents, size, is_mutable);
  
  		// first pass: get length in utf8 units
  		size_t length = prefix_length + latin1_decoder::process(postfix, postfix_length, 0, utf8_counter());
  
  		// allocate buffer of suitable length
  		char_t* buffer = static_cast<char_t*>(xml_memory::allocate((length + 1) * sizeof(char_t)));
  		if (!buffer) return false;
  
  		// second pass: convert latin1 input to utf8
  		memcpy(buffer, data, prefix_length);
  
  		uint8_t* obegin = reinterpret_cast<uint8_t*>(buffer);
  		uint8_t* oend = latin1_decoder::process(postfix, postfix_length, obegin + prefix_length, utf8_writer());
  
  		assert(oend == obegin + length);
  		*oend = 0;
  
  		out_buffer = buffer;
  		out_length = length + 1;
  
  		return true;
  	}
  
  	PUGI__FN bool convert_buffer(char_t*& out_buffer, size_t& out_length, xml_encoding encoding, const void* contents, size_t size, bool is_mutable)
  	{
  		// fast path: no conversion required
  		if (encoding == encoding_utf8)
  			return get_mutable_buffer(out_buffer, out_length, contents, size, is_mutable);
  
  		// source encoding is utf16
  		if (encoding == encoding_utf16_be || encoding == encoding_utf16_le)
  		{
  			xml_encoding native_encoding = is_little_endian() ? encoding_utf16_le : encoding_utf16_be;
  
  			return (native_encoding == encoding) ?
  				convert_buffer_generic(out_buffer, out_length, contents, size, utf16_decoder<opt_false>()) :
  				convert_buffer_generic(out_buffer, out_length, contents, size, utf16_decoder<opt_true>());
  		}
  
  		// source encoding is utf32
  		if (encoding == encoding_utf32_be || encoding == encoding_utf32_le)
  		{
  			xml_encoding native_encoding = is_little_endian() ? encoding_utf32_le : encoding_utf32_be;
  
  			return (native_encoding == encoding) ?
  				convert_buffer_generic(out_buffer, out_length, contents, size, utf32_decoder<opt_false>()) :
  				convert_buffer_generic(out_buffer, out_length, contents, size, utf32_decoder<opt_true>());
  		}
  
  		// source encoding is latin1
  		if (encoding == encoding_latin1)
  			return convert_buffer_latin1(out_buffer, out_length, contents, size, is_mutable);
  
  		assert(false && "Invalid encoding"); // unreachable
  		return false;
  	}
  #endif
  
  	PUGI__FN size_t as_utf8_begin(const wchar_t* str, size_t length)
  	{
  		// get length in utf8 characters
  		return wchar_decoder::process(str, length, 0, utf8_counter());
  	}
  
  	PUGI__FN void as_utf8_end(char* buffer, size_t size, const wchar_t* str, size_t length)
  	{
  		// convert to utf8
  		uint8_t* begin = reinterpret_cast<uint8_t*>(buffer);
  		uint8_t* end = wchar_decoder::process(str, length, begin, utf8_writer());
  
  		assert(begin + size == end);
  		(void)!end;
  		(void)!size;
  	}
  
  #ifndef PUGIXML_NO_STL
  	PUGI__FN std::string as_utf8_impl(const wchar_t* str, size_t length)
  	{
  		// first pass: get length in utf8 characters
  		size_t size = as_utf8_begin(str, length);
  
  		// allocate resulting string
  		std::string result;
  		result.resize(size);
  
  		// second pass: convert to utf8
  		if (size > 0) as_utf8_end(&result[0], size, str, length);
  
  		return result;
  	}
  
  	PUGI__FN std::basic_string<wchar_t> as_wide_impl(const char* str, size_t size)
  	{
  		const uint8_t* data = reinterpret_cast<const uint8_t*>(str);
  
  		// first pass: get length in wchar_t units
  		size_t length = utf8_decoder::process(data, size, 0, wchar_counter());
  
  		// allocate resulting string
  		std::basic_string<wchar_t> result;
  		result.resize(length);
  
  		// second pass: convert to wchar_t
  		if (length > 0)
  		{
  			wchar_writer::value_type begin = reinterpret_cast<wchar_writer::value_type>(&result[0]);
  			wchar_writer::value_type end = utf8_decoder::process(data, size, begin, wchar_writer());
  
  			assert(begin + length == end);
  			(void)!end;
  		}
  
  		return result;
  	}
  #endif
  
  	template <typename Header>
  	inline bool strcpy_insitu_allow(size_t length, const Header& header, uintptr_t header_mask, char_t* target)
  	{
  		// never reuse shared memory
  		if (header & xml_memory_page_contents_shared_mask) return false;
  
  		size_t target_length = strlength(target);
  
  		// always reuse document buffer memory if possible
  		if ((header & header_mask) == 0) return target_length >= length;
  
  		// reuse heap memory if waste is not too great
  		const size_t reuse_threshold = 32;
  
  		return target_length >= length && (target_length < reuse_threshold || target_length - length < target_length / 2);
  	}
  
  	template <typename String, typename Header>
  	PUGI__FN bool strcpy_insitu(String& dest, Header& header, uintptr_t header_mask, const char_t* source, size_t source_length)
  	{
  		if (source_length == 0)
  		{
  			// empty string and null pointer are equivalent, so just deallocate old memory
  			xml_allocator* alloc = PUGI__GETPAGE_IMPL(header)->allocator;
  
  			if (header & header_mask) alloc->deallocate_string(dest);
  
  			// mark the string as not allocated
  			dest = 0;
  			header &= ~header_mask;
  
  			return true;
  		}
  		else if (dest && strcpy_insitu_allow(source_length, header, header_mask, dest))
  		{
  			// we can reuse old buffer, so just copy the new data (including zero terminator)
  			memcpy(dest, source, source_length * sizeof(char_t));
  			dest[source_length] = 0;
  
  			return true;
  		}
  		else
  		{
  			xml_allocator* alloc = PUGI__GETPAGE_IMPL(header)->allocator;
  
  			if (!alloc->reserve()) return false;
  
  			// allocate new buffer
  			char_t* buf = alloc->allocate_string(source_length + 1);
  			if (!buf) return false;
  
  			// copy the string (including zero terminator)
  			memcpy(buf, source, source_length * sizeof(char_t));
  			buf[source_length] = 0;
  
  			// deallocate old buffer (*after* the above to protect against overlapping memory and/or allocation failures)
  			if (header & header_mask) alloc->deallocate_string(dest);
  
  			// the string is now allocated, so set the flag
  			dest = buf;
  			header |= header_mask;
  
  			return true;
  		}
  	}
  
  	struct gap
  	{
  		char_t* end;
  		size_t size;
  
  		gap(): end(0), size(0)
  		{
  		}
  
  		// Push new gap, move s count bytes further (skipping the gap).
  		// Collapse previous gap.
  		void push(char_t*& s, size_t count)
  		{
  			if (end) // there was a gap already; collapse it
  			{
  				// Move [old_gap_end, new_gap_start) to [old_gap_start, ...)
  				assert(s >= end);
  				memmove(end - size, end, reinterpret_cast<char*>(s) - reinterpret_cast<char*>(end));
  			}
  
  			s += count; // end of current gap
  
  			// "merge" two gaps
  			end = s;
  			size += count;
  		}
  
  		// Collapse all gaps, return past-the-end pointer
  		char_t* flush(char_t* s)
  		{
  			if (end)
  			{
  				// Move [old_gap_end, current_pos) to [old_gap_start, ...)
  				assert(s >= end);
  				memmove(end - size, end, reinterpret_cast<char*>(s) - reinterpret_cast<char*>(end));
  
  				return s - size;
  			}
  			else return s;
  		}
  	};
  
  	PUGI__FN char_t* strconv_escape(char_t* s, gap& g)
  	{
  		char_t* stre = s + 1;
  
  		switch (*stre)
  		{
  			case '#':	// &#...
  			{
  				unsigned int ucsc = 0;
  
  				if (stre[1] == 'x') // &#x... (hex code)
  				{
  					stre += 2;
  
  					char_t ch = *stre;
  
  					if (ch == ';') return stre;
  
  					for (;;)
  					{
  						if (static_cast<unsigned int>(ch - '0') <= 9)
  							ucsc = 16 * ucsc + (ch - '0');
  						else if (static_cast<unsigned int>((ch | ' ') - 'a') <= 5)
  							ucsc = 16 * ucsc + ((ch | ' ') - 'a' + 10);
  						else if (ch == ';')
  							break;
  						else // cancel
  							return stre;
  
  						ch = *++stre;
  					}
  
  					++stre;
  				}
  				else	// &#... (dec code)
  				{
  					char_t ch = *++stre;
  
  					if (ch == ';') return stre;
  
  					for (;;)
  					{
  						if (static_cast<unsigned int>(ch - '0') <= 9)
  							ucsc = 10 * ucsc + (ch - '0');
  						else if (ch == ';')
  							break;
  						else // cancel
  							return stre;
  
  						ch = *++stre;
  					}
  
  					++stre;
  				}
  
  			#ifdef PUGIXML_WCHAR_MODE
  				s = reinterpret_cast<char_t*>(wchar_writer::any(reinterpret_cast<wchar_writer::value_type>(s), ucsc));
  			#else
  				s = reinterpret_cast<char_t*>(utf8_writer::any(reinterpret_cast<uint8_t*>(s), ucsc));
  			#endif
  
  				g.push(s, stre - s);
  				return stre;
  			}
  
  			case 'a':	// &a
  			{
  				++stre;
  
  				if (*stre == 'm') // &am
  				{
  					if (*++stre == 'p' && *++stre == ';') // &amp;
  					{
  						*s++ = '&';
  						++stre;
  
  						g.push(s, stre - s);
  						return stre;
  					}
  				}
  				else if (*stre == 'p') // &ap
  				{
  					if (*++stre == 'o' && *++stre == 's' && *++stre == ';') // &apos;
  					{
  						*s++ = '\'';
  						++stre;
  
  						g.push(s, stre - s);
  						return stre;
  					}
  				}
  				break;
  			}
  
  			case 'g': // &g
  			{
  				if (*++stre == 't' && *++stre == ';') // &gt;
  				{
  					*s++ = '>';
  					++stre;
  
  					g.push(s, stre - s);
  					return stre;
  				}
  				break;
  			}
  
  			case 'l': // &l
  			{
  				if (*++stre == 't' && *++stre == ';') // &lt;
  				{
  					*s++ = '<';
  					++stre;
  
  					g.push(s, stre - s);
  					return stre;
  				}
  				break;
  			}
  
  			case 'q': // &q
  			{
  				if (*++stre == 'u' && *++stre == 'o' && *++stre == 't' && *++stre == ';') // &quot;
  				{
  					*s++ = '"';
  					++stre;
  
  					g.push(s, stre - s);
  					return stre;
  				}
  				break;
  			}
  
  			default:
  				break;
  		}
  
  		return stre;
  	}
  
  	// Parser utilities
  	#define PUGI__ENDSWITH(c, e)        ((c) == (e) || ((c) == 0 && endch == (e)))
  	#define PUGI__SKIPWS()              { while (PUGI__IS_CHARTYPE(*s, ct_space)) ++s; }
  	#define PUGI__OPTSET(OPT)           ( optmsk & (OPT) )
  	#define PUGI__PUSHNODE(TYPE)        { cursor = append_new_node(cursor, *alloc, TYPE); if (!cursor) PUGI__THROW_ERROR(status_out_of_memory, s); }
  	#define PUGI__POPNODE()             { cursor = cursor->parent; }
  	#define PUGI__SCANFOR(X)            { while (*s != 0 && !(X)) ++s; }
  	#define PUGI__SCANWHILE(X)          { while (X) ++s; }
  	#define PUGI__SCANWHILE_UNROLL(X)   { for (;;) { char_t ss = s[0]; if (PUGI__UNLIKELY(!(X))) { break; } ss = s[1]; if (PUGI__UNLIKELY(!(X))) { s += 1; break; } ss = s[2]; if (PUGI__UNLIKELY(!(X))) { s += 2; break; } ss = s[3]; if (PUGI__UNLIKELY(!(X))) { s += 3; break; } s += 4; } }
  	#define PUGI__ENDSEG()              { ch = *s; *s = 0; ++s; }
  	#define PUGI__THROW_ERROR(err, m)   return error_offset = m, error_status = err, static_cast<char_t*>(0)
  	#define PUGI__CHECK_ERROR(err, m)   { if (*s == 0) PUGI__THROW_ERROR(err, m); }
  
  	PUGI__FN char_t* strconv_comment(char_t* s, char_t endch)
  	{
  		gap g;
  
  		while (true)
  		{
  			PUGI__SCANWHILE_UNROLL(!PUGI__IS_CHARTYPE(ss, ct_parse_comment));
  
  			if (*s == '\r') // Either a single 0x0d or 0x0d 0x0a pair
  			{
  				*s++ = '\n'; // replace first one with 0x0a
  
  				if (*s == '\n') g.push(s, 1);
  			}
  			else if (s[0] == '-' && s[1] == '-' && PUGI__ENDSWITH(s[2], '>')) // comment ends here
  			{
  				*g.flush(s) = 0;
  
  				return s + (s[2] == '>' ? 3 : 2);
  			}
  			else if (*s == 0)
  			{
  				return 0;
  			}
  			else ++s;
  		}
  	}
  
  	PUGI__FN char_t* strconv_cdata(char_t* s, char_t endch)
  	{
  		gap g;
  
  		while (true)
  		{
  			PUGI__SCANWHILE_UNROLL(!PUGI__IS_CHARTYPE(ss, ct_parse_cdata));
  
  			if (*s == '\r') // Either a single 0x0d or 0x0d 0x0a pair
  			{
  				*s++ = '\n'; // replace first one with 0x0a
  
  				if (*s == '\n') g.push(s, 1);
  			}
  			else if (s[0] == ']' && s[1] == ']' && PUGI__ENDSWITH(s[2], '>')) // CDATA ends here
  			{
  				*g.flush(s) = 0;
  
  				return s + 1;
  			}
  			else if (*s == 0)
  			{
  				return 0;
  			}
  			else ++s;
  		}
  	}
  
  	typedef char_t* (*strconv_pcdata_t)(char_t*);
  
  	template <typename opt_trim, typename opt_eol, typename opt_escape> struct strconv_pcdata_impl
  	{
  		static char_t* parse(char_t* s)
  		{
  			gap g;
  
  			char_t* begin = s;
  
  			while (true)
  			{
  				PUGI__SCANWHILE_UNROLL(!PUGI__IS_CHARTYPE(ss, ct_parse_pcdata));
  
  				if (*s == '<') // PCDATA ends here
  				{
  					char_t* end = g.flush(s);
  
  					if (opt_trim::value)
  						while (end > begin && PUGI__IS_CHARTYPE(end[-1], ct_space))
  							--end;
  
  					*end = 0;
  
  					return s + 1;
  				}
  				else if (opt_eol::value && *s == '\r') // Either a single 0x0d or 0x0d 0x0a pair
  				{
  					*s++ = '\n'; // replace first one with 0x0a
  
  					if (*s == '\n') g.push(s, 1);
  				}
  				else if (opt_escape::value && *s == '&')
  				{
  					s = strconv_escape(s, g);
  				}
  				else if (*s == 0)
  				{
  					char_t* end = g.flush(s);
  
  					if (opt_trim::value)
  						while (end > begin && PUGI__IS_CHARTYPE(end[-1], ct_space))
  							--end;
  
  					*end = 0;
  
  					return s;
  				}
  				else ++s;
  			}
  		}
  	};
  
  	PUGI__FN strconv_pcdata_t get_strconv_pcdata(unsigned int optmask)
  	{
  		PUGI__STATIC_ASSERT(parse_escapes == 0x10 && parse_eol == 0x20 && parse_trim_pcdata == 0x0800);
  
  		switch (((optmask >> 4) & 3) | ((optmask >> 9) & 4)) // get bitmask for flags (eol escapes trim)
  		{
  		case 0: return strconv_pcdata_impl<opt_false, opt_false, opt_false>::parse;
  		case 1: return strconv_pcdata_impl<opt_false, opt_false, opt_true>::parse;
  		case 2: return strconv_pcdata_impl<opt_false, opt_true, opt_false>::parse;
  		case 3: return strconv_pcdata_impl<opt_false, opt_true, opt_true>::parse;
  		case 4: return strconv_pcdata_impl<opt_true, opt_false, opt_false>::parse;
  		case 5: return strconv_pcdata_impl<opt_true, opt_false, opt_true>::parse;
  		case 6: return strconv_pcdata_impl<opt_true, opt_true, opt_false>::parse;
  		case 7: return strconv_pcdata_impl<opt_true, opt_true, opt_true>::parse;
  		default: assert(false); return 0; // unreachable
  		}
  	}
  
  	typedef char_t* (*strconv_attribute_t)(char_t*, char_t);
  
  	template <typename opt_escape> struct strconv_attribute_impl
  	{
  		static char_t* parse_wnorm(char_t* s, char_t end_quote)
  		{
  			gap g;
  
  			// trim leading whitespaces
  			if (PUGI__IS_CHARTYPE(*s, ct_space))
  			{
  				char_t* str = s;
  
  				do ++str;
  				while (PUGI__IS_CHARTYPE(*str, ct_space));
  
  				g.push(s, str - s);
  			}
  
  			while (true)
  			{
  				PUGI__SCANWHILE_UNROLL(!PUGI__IS_CHARTYPE(ss, ct_parse_attr_ws | ct_space));
  
  				if (*s == end_quote)
  				{
  					char_t* str = g.flush(s);
  
  					do *str-- = 0;
  					while (PUGI__IS_CHARTYPE(*str, ct_space));
  
  					return s + 1;
  				}
  				else if (PUGI__IS_CHARTYPE(*s, ct_space))
  				{
  					*s++ = ' ';
  
  					if (PUGI__IS_CHARTYPE(*s, ct_space))
  					{
  						char_t* str = s + 1;
  						while (PUGI__IS_CHARTYPE(*str, ct_space)) ++str;
  
  						g.push(s, str - s);
  					}
  				}
  				else if (opt_escape::value && *s == '&')
  				{
  					s = strconv_escape(s, g);
  				}
  				else if (!*s)
  				{
  					return 0;
  				}
  				else ++s;
  			}
  		}
  
  		static char_t* parse_wconv(char_t* s, char_t end_quote)
  		{
  			gap g;
  
  			while (true)
  			{
  				PUGI__SCANWHILE_UNROLL(!PUGI__IS_CHARTYPE(ss, ct_parse_attr_ws));
  
  				if (*s == end_quote)
  				{
  					*g.flush(s) = 0;
  
  					return s + 1;
  				}
  				else if (PUGI__IS_CHARTYPE(*s, ct_space))
  				{
  					if (*s == '\r')
  					{
  						*s++ = ' ';
  
  						if (*s == '\n') g.push(s, 1);
  					}
  					else *s++ = ' ';
  				}
  				else if (opt_escape::value && *s == '&')
  				{
  					s = strconv_escape(s, g);
  				}
  				else if (!*s)
  				{
  					return 0;
  				}
  				else ++s;
  			}
  		}
  
  		static char_t* parse_eol(char_t* s, char_t end_quote)
  		{
  			gap g;
  
  			while (true)
  			{
  				PUGI__SCANWHILE_UNROLL(!PUGI__IS_CHARTYPE(ss, ct_parse_attr));
  
  				if (*s == end_quote)
  				{
  					*g.flush(s) = 0;
  
  					return s + 1;
  				}
  				else if (*s == '\r')
  				{
  					*s++ = '\n';
  
  					if (*s == '\n') g.push(s, 1);
  				}
  				else if (opt_escape::value && *s == '&')
  				{
  					s = strconv_escape(s, g);
  				}
  				else if (!*s)
  				{
  					return 0;
  				}
  				else ++s;
  			}
  		}
  
  		static char_t* parse_simple(char_t* s, char_t end_quote)
  		{
  			gap g;
  
  			while (true)
  			{
  				PUGI__SCANWHILE_UNROLL(!PUGI__IS_CHARTYPE(ss, ct_parse_attr));
  
  				if (*s == end_quote)
  				{
  					*g.flush(s) = 0;
  
  					return s + 1;
  				}
  				else if (opt_escape::value && *s == '&')
  				{
  					s = strconv_escape(s, g);
  				}
  				else if (!*s)
  				{
  					return 0;
  				}
  				else ++s;
  			}
  		}
  	};
  
  	PUGI__FN strconv_attribute_t get_strconv_attribute(unsigned int optmask)
  	{
  		PUGI__STATIC_ASSERT(parse_escapes == 0x10 && parse_eol == 0x20 && parse_wconv_attribute == 0x40 && parse_wnorm_attribute == 0x80);
  
  		switch ((optmask >> 4) & 15) // get bitmask for flags (wconv wnorm eol escapes)
  		{
  		case 0:  return strconv_attribute_impl<opt_false>::parse_simple;
  		case 1:  return strconv_attribute_impl<opt_true>::parse_simple;
  		case 2:  return strconv_attribute_impl<opt_false>::parse_eol;
  		case 3:  return strconv_attribute_impl<opt_true>::parse_eol;
  		case 4:  return strconv_attribute_impl<opt_false>::parse_wconv;
  		case 5:  return strconv_attribute_impl<opt_true>::parse_wconv;
  		case 6:  return strconv_attribute_impl<opt_false>::parse_wconv;
  		case 7:  return strconv_attribute_impl<opt_true>::parse_wconv;
  		case 8:  return strconv_attribute_impl<opt_false>::parse_wnorm;
  		case 9:  return strconv_attribute_impl<opt_true>::parse_wnorm;
  		case 10: return strconv_attribute_impl<opt_false>::parse_wnorm;
  		case 11: return strconv_attribute_impl<opt_true>::parse_wnorm;
  		case 12: return strconv_attribute_impl<opt_false>::parse_wnorm;
  		case 13: return strconv_attribute_impl<opt_true>::parse_wnorm;
  		case 14: return strconv_attribute_impl<opt_false>::parse_wnorm;
  		case 15: return strconv_attribute_impl<opt_true>::parse_wnorm;
  		default: assert(false); return 0; // unreachable
  		}
  	}
  
  	inline xml_parse_result make_parse_result(xml_parse_status status, ptrdiff_t offset = 0)
  	{
  		xml_parse_result result;
  		result.status = status;
  		result.offset = offset;
  
  		return result;
  	}
  
  	struct xml_parser
  	{
  		xml_allocator* alloc;
  		char_t* error_offset;
  		xml_parse_status error_status;
  
  		xml_parser(xml_allocator* alloc_): alloc(alloc_), error_offset(0), error_status(status_ok)
  		{
  		}
  
  		// DOCTYPE consists of nested sections of the following possible types:
  		// <!-- ... -->, <? ... ?>, "...", '...'
  		// <![...]]>
  		// <!...>
  		// First group can not contain nested groups
  		// Second group can contain nested groups of the same type
  		// Third group can contain all other groups
  		char_t* parse_doctype_primitive(char_t* s)
  		{
  			if (*s == '"' || *s == '\'')
  			{
  				// quoted string
  				char_t ch = *s++;
  				PUGI__SCANFOR(*s == ch);
  				if (!*s) PUGI__THROW_ERROR(status_bad_doctype, s);
  
  				s++;
  			}
  			else if (s[0] == '<' && s[1] == '?')
  			{
  				// <? ... ?>
  				s += 2;
  				PUGI__SCANFOR(s[0] == '?' && s[1] == '>'); // no need for ENDSWITH because ?> can't terminate proper doctype
  				if (!*s) PUGI__THROW_ERROR(status_bad_doctype, s);
  
  				s += 2;
  			}
  			else if (s[0] == '<' && s[1] == '!' && s[2] == '-' && s[3] == '-')
  			{
  				s += 4;
  				PUGI__SCANFOR(s[0] == '-' && s[1] == '-' && s[2] == '>'); // no need for ENDSWITH because --> can't terminate proper doctype
  				if (!*s) PUGI__THROW_ERROR(status_bad_doctype, s);
  
  				s += 3;
  			}
  			else PUGI__THROW_ERROR(status_bad_doctype, s);
  
  			return s;
  		}
  
  		char_t* parse_doctype_ignore(char_t* s)
  		{
  			size_t depth = 0;
  
  			assert(s[0] == '<' && s[1] == '!' && s[2] == '[');
  			s += 3;
  
  			while (*s)
  			{
  				if (s[0] == '<' && s[1] == '!' && s[2] == '[')
  				{
  					// nested ignore section
  					s += 3;
  					depth++;
  				}
  				else if (s[0] == ']' && s[1] == ']' && s[2] == '>')
  				{
  					// ignore section end
  					s += 3;
  
  					if (depth == 0)
  						return s;
  
  					depth--;
  				}
  				else s++;
  			}
  
  			PUGI__THROW_ERROR(status_bad_doctype, s);
  		}
  
  		char_t* parse_doctype_group(char_t* s, char_t endch)
  		{
  			size_t depth = 0;
  
  			assert((s[0] == '<' || s[0] == 0) && s[1] == '!');
  			s += 2;
  
  			while (*s)
  			{
  				if (s[0] == '<' && s[1] == '!' && s[2] != '-')
  				{
  					if (s[2] == '[')
  					{
  						// ignore
  						s = parse_doctype_ignore(s);
  						if (!s) return s;
  					}
  					else
  					{
  						// some control group
  						s += 2;
  						depth++;
  					}
  				}
  				else if (s[0] == '<' || s[0] == '"' || s[0] == '\'')
  				{
  					// unknown tag (forbidden), or some primitive group
  					s = parse_doctype_primitive(s);
  					if (!s) return s;
  				}
  				else if (*s == '>')
  				{
  					if (depth == 0)
  						return s;
  
  					depth--;
  					s++;
  				}
  				else s++;
  			}
  
  			if (depth != 0 || endch != '>') PUGI__THROW_ERROR(status_bad_doctype, s);
  
  			return s;
  		}
  
  		char_t* parse_exclamation(char_t* s, xml_node_struct* cursor, unsigned int optmsk, char_t endch)
  		{
  			// parse node contents, starting with exclamation mark
  			++s;
  
  			if (*s == '-') // '<!-...'
  			{
  				++s;
  
  				if (*s == '-') // '<!--...'
  				{
  					++s;
  
  					if (PUGI__OPTSET(parse_comments))
  					{
  						PUGI__PUSHNODE(node_comment); // Append a new node on the tree.
  						cursor->value = s; // Save the offset.
  					}
  
  					if (PUGI__OPTSET(parse_eol) && PUGI__OPTSET(parse_comments))
  					{
  						s = strconv_comment(s, endch);
  
  						if (!s) PUGI__THROW_ERROR(status_bad_comment, cursor->value);
  					}
  					else
  					{
  						// Scan for terminating '-->'.
  						PUGI__SCANFOR(s[0] == '-' && s[1] == '-' && PUGI__ENDSWITH(s[2], '>'));
  						PUGI__CHECK_ERROR(status_bad_comment, s);
  
  						if (PUGI__OPTSET(parse_comments))
  							*s = 0; // Zero-terminate this segment at the first terminating '-'.
  
  						s += (s[2] == '>' ? 3 : 2); // Step over the '\0->'.
  					}
  				}
  				else PUGI__THROW_ERROR(status_bad_comment, s);
  			}
  			else if (*s == '[')
  			{
  				// '<![CDATA[...'
  				if (*++s=='C' && *++s=='D' && *++s=='A' && *++s=='T' && *++s=='A' && *++s == '[')
  				{
  					++s;
  
  					if (PUGI__OPTSET(parse_cdata))
  					{
  						PUGI__PUSHNODE(node_cdata); // Append a new node on the tree.
  						cursor->value = s; // Save the offset.
  
  						if (PUGI__OPTSET(parse_eol))
  						{
  							s = strconv_cdata(s, endch);
  
  							if (!s) PUGI__THROW_ERROR(status_bad_cdata, cursor->value);
  						}
  						else
  						{
  							// Scan for terminating ']]>'.
  							PUGI__SCANFOR(s[0] == ']' && s[1] == ']' && PUGI__ENDSWITH(s[2], '>'));
  							PUGI__CHECK_ERROR(status_bad_cdata, s);
  
  							*s++ = 0; // Zero-terminate this segment.
  						}
  					}
  					else // Flagged for discard, but we still have to scan for the terminator.
  					{
  						// Scan for terminating ']]>'.
  						PUGI__SCANFOR(s[0] == ']' && s[1] == ']' && PUGI__ENDSWITH(s[2], '>'));
  						PUGI__CHECK_ERROR(status_bad_cdata, s);
  
  						++s;
  					}
  
  					s += (s[1] == '>' ? 2 : 1); // Step over the last ']>'.
  				}
  				else PUGI__THROW_ERROR(status_bad_cdata, s);
  			}
  			else if (s[0] == 'D' && s[1] == 'O' && s[2] == 'C' && s[3] == 'T' && s[4] == 'Y' && s[5] == 'P' && PUGI__ENDSWITH(s[6], 'E'))
  			{
  				s -= 2;
  
  				if (cursor->parent) PUGI__THROW_ERROR(status_bad_doctype, s);
  
  				char_t* mark = s + 9;
  
  				s = parse_doctype_group(s, endch);
  				if (!s) return s;
  
  				assert((*s == 0 && endch == '>') || *s == '>');
  				if (*s) *s++ = 0;
  
  				if (PUGI__OPTSET(parse_doctype))
  				{
  					while (PUGI__IS_CHARTYPE(*mark, ct_space)) ++mark;
  
  					PUGI__PUSHNODE(node_doctype);
  
  					cursor->value = mark;
  				}
  			}
  			else if (*s == 0 && endch == '-') PUGI__THROW_ERROR(status_bad_comment, s);
  			else if (*s == 0 && endch == '[') PUGI__THROW_ERROR(status_bad_cdata, s);
  			else PUGI__THROW_ERROR(status_unrecognized_tag, s);
  
  			return s;
  		}
  
  		char_t* parse_question(char_t* s, xml_node_struct*& ref_cursor, unsigned int optmsk, char_t endch)
  		{
  			// load into registers
  			xml_node_struct* cursor = ref_cursor;
  			char_t ch = 0;
  
  			// parse node contents, starting with question mark
  			++s;
  
  			// read PI target
  			char_t* target = s;
  
  			if (!PUGI__IS_CHARTYPE(*s, ct_start_symbol)) PUGI__THROW_ERROR(status_bad_pi, s);
  
  			PUGI__SCANWHILE(PUGI__IS_CHARTYPE(*s, ct_symbol));
  			PUGI__CHECK_ERROR(status_bad_pi, s);
  
  			// determine node type; stricmp / strcasecmp is not portable
  			bool declaration = (target[0] | ' ') == 'x' && (target[1] | ' ') == 'm' && (target[2] | ' ') == 'l' && target + 3 == s;
  
  			if (declaration ? PUGI__OPTSET(parse_declaration) : PUGI__OPTSET(parse_pi))
  			{
  				if (declaration)
  				{
  					// disallow non top-level declarations
  					if (cursor->parent) PUGI__THROW_ERROR(status_bad_pi, s);
  
  					PUGI__PUSHNODE(node_declaration);
  				}
  				else
  				{
  					PUGI__PUSHNODE(node_pi);
  				}
  
  				cursor->name = target;
  
  				PUGI__ENDSEG();
  
  				// parse value/attributes
  				if (ch == '?')
  				{
  					// empty node
  					if (!PUGI__ENDSWITH(*s, '>')) PUGI__THROW_ERROR(status_bad_pi, s);
  					s += (*s == '>');
  
  					PUGI__POPNODE();
  				}
  				else if (PUGI__IS_CHARTYPE(ch, ct_space))
  				{
  					PUGI__SKIPWS();
  
  					// scan for tag end
  					char_t* value = s;
  
  					PUGI__SCANFOR(s[0] == '?' && PUGI__ENDSWITH(s[1], '>'));
  					PUGI__CHECK_ERROR(status_bad_pi, s);
  
  					if (declaration)
  					{
  						// replace ending ? with / so that 'element' terminates properly
  						*s = '/';
  
  						// we exit from this function with cursor at node_declaration, which is a signal to parse() to go to LOC_ATTRIBUTES
  						s = value;
  					}
  					else
  					{
  						// store value and step over >
  						cursor->value = value;
  
  						PUGI__POPNODE();
  
  						PUGI__ENDSEG();
  
  						s += (*s == '>');
  					}
  				}
  				else PUGI__THROW_ERROR(status_bad_pi, s);
  			}
  			else
  			{
  				// scan for tag end
  				PUGI__SCANFOR(s[0] == '?' && PUGI__ENDSWITH(s[1], '>'));
  				PUGI__CHECK_ERROR(status_bad_pi, s);
  
  				s += (s[1] == '>' ? 2 : 1);
  			}
  
  			// store from registers
  			ref_cursor = cursor;
  
  			return s;
  		}
  
  		char_t* parse_tree(char_t* s, xml_node_struct* root, unsigned int optmsk, char_t endch)
  		{
  			strconv_attribute_t strconv_attribute = get_strconv_attribute(optmsk);
  			strconv_pcdata_t strconv_pcdata = get_strconv_pcdata(optmsk);
  
  			char_t ch = 0;
  			xml_node_struct* cursor = root;
  			char_t* mark = s;
  
  			while (*s != 0)
  			{
  				if (*s == '<')
  				{
  					++s;
  
  				LOC_TAG:
  					if (PUGI__IS_CHARTYPE(*s, ct_start_symbol)) // '<#...'
  					{
  						PUGI__PUSHNODE(node_element); // Append a new node to the tree.
  
  						cursor->name = s;
  
  						PUGI__SCANWHILE_UNROLL(PUGI__IS_CHARTYPE(ss, ct_symbol)); // Scan for a terminator.
  						PUGI__ENDSEG(); // Save char in 'ch', terminate & step over.
  
  						if (ch == '>')
  						{
  							// end of tag
  						}
  						else if (PUGI__IS_CHARTYPE(ch, ct_space))
  						{
  						LOC_ATTRIBUTES:
  							while (true)
  							{
  								PUGI__SKIPWS(); // Eat any whitespace.
  
  								if (PUGI__IS_CHARTYPE(*s, ct_start_symbol)) // <... #...
  								{
  									xml_attribute_struct* a = append_new_attribute(cursor, *alloc); // Make space for this attribute.
  									if (!a) PUGI__THROW_ERROR(status_out_of_memory, s);
  
  									a->name = s; // Save the offset.
  
  									PUGI__SCANWHILE_UNROLL(PUGI__IS_CHARTYPE(ss, ct_symbol)); // Scan for a terminator.
  									PUGI__ENDSEG(); // Save char in 'ch', terminate & step over.
  
  									if (PUGI__IS_CHARTYPE(ch, ct_space))
  									{
  										PUGI__SKIPWS(); // Eat any whitespace.
  
  										ch = *s;
  										++s;
  									}
  
  									if (ch == '=') // '<... #=...'
  									{
  										PUGI__SKIPWS(); // Eat any whitespace.
  
  										if (*s == '"' || *s == '\'') // '<... #="...'
  										{
  											ch = *s; // Save quote char to avoid breaking on "''" -or- '""'.
  											++s; // Step over the quote.
  											a->value = s; // Save the offset.
  
  											s = strconv_attribute(s, ch);
  
  											if (!s) PUGI__THROW_ERROR(status_bad_attribute, a->value);
  
  											// After this line the loop continues from the start;
  											// Whitespaces, / and > are ok, symbols and EOF are wrong,
  											// everything else will be detected
  											if (PUGI__IS_CHARTYPE(*s, ct_start_symbol)) PUGI__THROW_ERROR(status_bad_attribute, s);
  										}
  										else PUGI__THROW_ERROR(status_bad_attribute, s);
  									}
  									else PUGI__THROW_ERROR(status_bad_attribute, s);
  								}
  								else if (*s == '/')
  								{
  									++s;
  
  									if (*s == '>')
  									{
  										PUGI__POPNODE();
  										s++;
  										break;
  									}
  									else if (*s == 0 && endch == '>')
  									{
  										PUGI__POPNODE();
  										break;
  									}
  									else PUGI__THROW_ERROR(status_bad_start_element, s);
  								}
  								else if (*s == '>')
  								{
  									++s;
  
  									break;
  								}
  								else if (*s == 0 && endch == '>')
  								{
  									break;
  								}
  								else PUGI__THROW_ERROR(status_bad_start_element, s);
  							}
  
  							// !!!
  						}
  						else if (ch == '/') // '<#.../'
  						{
  							if (!PUGI__ENDSWITH(*s, '>')) PUGI__THROW_ERROR(status_bad_start_element, s);
  
  							PUGI__POPNODE(); // Pop.
  
  							s += (*s == '>');
  						}
  						else if (ch == 0)
  						{
  							// we stepped over null terminator, backtrack & handle closing tag
  							--s;
  
  							if (endch != '>') PUGI__THROW_ERROR(status_bad_start_element, s);
  						}
  						else PUGI__THROW_ERROR(status_bad_start_element, s);
  					}
  					else if (*s == '/')
  					{
  						++s;
  
  						mark = s;
  
  						char_t* name = cursor->name;
  						if (!name) PUGI__THROW_ERROR(status_end_element_mismatch, mark);
  
  						while (PUGI__IS_CHARTYPE(*s, ct_symbol))
  						{
  							if (*s++ != *name++) PUGI__THROW_ERROR(status_end_element_mismatch, mark);
  						}
  
  						if (*name)
  						{
  							if (*s == 0 && name[0] == endch && name[1] == 0) PUGI__THROW_ERROR(status_bad_end_element, s);
  							else PUGI__THROW_ERROR(status_end_element_mismatch, mark);
  						}
  
  						PUGI__POPNODE(); // Pop.
  
  						PUGI__SKIPWS();
  
  						if (*s == 0)
  						{
  							if (endch != '>') PUGI__THROW_ERROR(status_bad_end_element, s);
  						}
  						else
  						{
  							if (*s != '>') PUGI__THROW_ERROR(status_bad_end_element, s);
  							++s;
  						}
  					}
  					else if (*s == '?') // '<?...'
  					{
  						s = parse_question(s, cursor, optmsk, endch);
  						if (!s) return s;
  
  						assert(cursor);
  						if (PUGI__NODETYPE(cursor) == node_declaration) goto LOC_ATTRIBUTES;
  					}
  					else if (*s == '!') // '<!...'
  					{
  						s = parse_exclamation(s, cursor, optmsk, endch);
  						if (!s) return s;
  					}
  					else if (*s == 0 && endch == '?') PUGI__THROW_ERROR(status_bad_pi, s);
  					else PUGI__THROW_ERROR(status_unrecognized_tag, s);
  				}
  				else
  				{
  					mark = s; // Save this offset while searching for a terminator.
  
  					PUGI__SKIPWS(); // Eat whitespace if no genuine PCDATA here.
  
  					if (*s == '<' || !*s)
  					{
  						// We skipped some whitespace characters because otherwise we would take the tag branch instead of PCDATA one
  						assert(mark != s);
  
  						if (!PUGI__OPTSET(parse_ws_pcdata | parse_ws_pcdata_single) || PUGI__OPTSET(parse_trim_pcdata))
  						{
  							continue;
  						}
  						else if (PUGI__OPTSET(parse_ws_pcdata_single))
  						{
  							if (s[0] != '<' || s[1] != '/' || cursor->first_child) continue;
  						}
  					}
  
  					if (!PUGI__OPTSET(parse_trim_pcdata))
  						s = mark;
  
  					if (cursor->parent || PUGI__OPTSET(parse_fragment))
  					{
  						if (PUGI__OPTSET(parse_embed_pcdata) && cursor->parent && !cursor->first_child && !cursor->value)
  						{
  							cursor->value = s; // Save the offset.
  						}
  						else
  						{
  							PUGI__PUSHNODE(node_pcdata); // Append a new node on the tree.
  
  							cursor->value = s; // Save the offset.
  
  							PUGI__POPNODE(); // Pop since this is a standalone.
  						}
  
  						s = strconv_pcdata(s);
  
  						if (!*s) break;
  					}
  					else
  					{
  						PUGI__SCANFOR(*s == '<'); // '...<'
  						if (!*s) break;
  
  						++s;
  					}
  
  					// We're after '<'
  					goto LOC_TAG;
  				}
  			}
  
  			// check that last tag is closed
  			if (cursor != root) PUGI__THROW_ERROR(status_end_element_mismatch, s);
  
  			return s;
  		}
  
  	#ifdef PUGIXML_WCHAR_MODE
  		static char_t* parse_skip_bom(char_t* s)
  		{
  			unsigned int bom = 0xfeff;
  			return (s[0] == static_cast<wchar_t>(bom)) ? s + 1 : s;
  		}
  	#else
  		static char_t* parse_skip_bom(char_t* s)
  		{
  			return (s[0] == '\xef' && s[1] == '\xbb' && s[2] == '\xbf') ? s + 3 : s;
  		}
  	#endif
  
  		static bool has_element_node_siblings(xml_node_struct* node)
  		{
  			while (node)
  			{
  				if (PUGI__NODETYPE(node) == node_element) return true;
  
  				node = node->next_sibling;
  			}
  
  			return false;
  		}
  
  		static xml_parse_result parse(char_t* buffer, size_t length, xml_document_struct* xmldoc, xml_node_struct* root, unsigned int optmsk)
  		{
  			// early-out for empty documents
  			if (length == 0)
  				return make_parse_result(PUGI__OPTSET(parse_fragment) ? status_ok : status_no_document_element);
  
  			// get last child of the root before parsing
  			xml_node_struct* last_root_child = root->first_child ? root->first_child->prev_sibling_c + 0 : 0;
  
  			// create parser on stack
  			xml_parser parser(static_cast<xml_allocator*>(xmldoc));
  
  			// save last character and make buffer zero-terminated (speeds up parsing)
  			char_t endch = buffer[length - 1];
  			buffer[length - 1] = 0;
  
  			// skip BOM to make sure it does not end up as part of parse output
  			char_t* buffer_data = parse_skip_bom(buffer);
  
  			// perform actual parsing
  			parser.parse_tree(buffer_data, root, optmsk, endch);
  
  			xml_parse_result result = make_parse_result(parser.error_status, parser.error_offset ? parser.error_offset - buffer : 0);
  			assert(result.offset >= 0 && static_cast<size_t>(result.offset) <= length);
  
  			if (result)
  			{
  				// since we removed last character, we have to handle the only possible false positive (stray <)
  				if (endch == '<')
  					return make_parse_result(status_unrecognized_tag, length - 1);
  
  				// check if there are any element nodes parsed
  				xml_node_struct* first_root_child_parsed = last_root_child ? last_root_child->next_sibling + 0 : root->first_child+ 0;
  
  				if (!PUGI__OPTSET(parse_fragment) && !has_element_node_siblings(first_root_child_parsed))
  					return make_parse_result(status_no_document_element, length - 1);
  			}
  			else
  			{
  				// roll back offset if it occurs on a null terminator in the source buffer
  				if (result.offset > 0 && static_cast<size_t>(result.offset) == length - 1 && endch == 0)
  					result.offset--;
  			}
  
  			return result;
  		}
  	};
  
  	// Output facilities
  	PUGI__FN xml_encoding get_write_native_encoding()
  	{
  	#ifdef PUGIXML_WCHAR_MODE
  		return get_wchar_encoding();
  	#else
  		return encoding_utf8;
  	#endif
  	}
  
  	PUGI__FN xml_encoding get_write_encoding(xml_encoding encoding)
  	{
  		// replace wchar encoding with utf implementation
  		if (encoding == encoding_wchar) return get_wchar_encoding();
  
  		// replace utf16 encoding with utf16 with specific endianness
  		if (encoding == encoding_utf16) return is_little_endian() ? encoding_utf16_le : encoding_utf16_be;
  
  		// replace utf32 encoding with utf32 with specific endianness
  		if (encoding == encoding_utf32) return is_little_endian() ? encoding_utf32_le : encoding_utf32_be;
  
  		// only do autodetection if no explicit encoding is requested
  		if (encoding != encoding_auto) return encoding;
  
  		// assume utf8 encoding
  		return encoding_utf8;
  	}
  
  	template <typename D, typename T> PUGI__FN size_t convert_buffer_output_generic(typename T::value_type dest, const char_t* data, size_t length, D, T)
  	{
  		PUGI__STATIC_ASSERT(sizeof(char_t) == sizeof(typename D::type));
  
  		typename T::value_type end = D::process(reinterpret_cast<const typename D::type*>(data), length, dest, T());
  
  		return static_cast<size_t>(end - dest) * sizeof(*dest);
  	}
  
  	template <typename D, typename T> PUGI__FN size_t convert_buffer_output_generic(typename T::value_type dest, const char_t* data, size_t length, D, T, bool opt_swap)
  	{
  		PUGI__STATIC_ASSERT(sizeof(char_t) == sizeof(typename D::type));
  
  		typename T::value_type end = D::process(reinterpret_cast<const typename D::type*>(data), length, dest, T());
  
  		if (opt_swap)
  		{
  			for (typename T::value_type i = dest; i != end; ++i)
  				*i = endian_swap(*i);
  		}
  
  		return static_cast<size_t>(end - dest) * sizeof(*dest);
  	}
  
  #ifdef PUGIXML_WCHAR_MODE
  	PUGI__FN size_t get_valid_length(const char_t* data, size_t length)
  	{
  		if (length < 1) return 0;
  
  		// discard last character if it's the lead of a surrogate pair
  		return (sizeof(wchar_t) == 2 && static_cast<unsigned int>(static_cast<uint16_t>(data[length - 1]) - 0xD800) < 0x400) ? length - 1 : length;
  	}
  
  	PUGI__FN size_t convert_buffer_output(char_t* r_char, uint8_t* r_u8, uint16_t* r_u16, uint32_t* r_u32, const char_t* data, size_t length, xml_encoding encoding)
  	{
  		// only endian-swapping is required
  		if (need_endian_swap_utf(encoding, get_wchar_encoding()))
  		{
  			convert_wchar_endian_swap(r_char, data, length);
  
  			return length * sizeof(char_t);
  		}
  
  		// convert to utf8
  		if (encoding == encoding_utf8)
  			return convert_buffer_output_generic(r_u8, data, length, wchar_decoder(), utf8_writer());
  
  		// convert to utf16
  		if (encoding == encoding_utf16_be || encoding == encoding_utf16_le)
  		{
  			xml_encoding native_encoding = is_little_endian() ? encoding_utf16_le : encoding_utf16_be;
  
  			return convert_buffer_output_generic(r_u16, data, length, wchar_decoder(), utf16_writer(), native_encoding != encoding);
  		}
  
  		// convert to utf32
  		if (encoding == encoding_utf32_be || encoding == encoding_utf32_le)
  		{
  			xml_encoding native_encoding = is_little_endian() ? encoding_utf32_le : encoding_utf32_be;
  
  			return convert_buffer_output_generic(r_u32, data, length, wchar_decoder(), utf32_writer(), native_encoding != encoding);
  		}
  
  		// convert to latin1
  		if (encoding == encoding_latin1)
  			return convert_buffer_output_generic(r_u8, data, length, wchar_decoder(), latin1_writer());
  
  		assert(false && "Invalid encoding"); // unreachable
  		return 0;
  	}
  #else
  	PUGI__FN size_t get_valid_length(const char_t* data, size_t length)
  	{
  		if (length < 5) return 0;
  
  		for (size_t i = 1; i <= 4; ++i)
  		{
  			uint8_t ch = static_cast<uint8_t>(data[length - i]);
  
  			// either a standalone character or a leading one
  			if ((ch & 0xc0) != 0x80) return length - i;
  		}
  
  		// there are four non-leading characters at the end, sequence tail is broken so might as well process the whole chunk
  		return length;
  	}
  
  	PUGI__FN size_t convert_buffer_output(char_t* /* r_char */, uint8_t* r_u8, uint16_t* r_u16, uint32_t* r_u32, const char_t* data, size_t length, xml_encoding encoding)
  	{
  		if (encoding == encoding_utf16_be || encoding == encoding_utf16_le)
  		{
  			xml_encoding native_encoding = is_little_endian() ? encoding_utf16_le : encoding_utf16_be;
  
  			return convert_buffer_output_generic(r_u16, data, length, utf8_decoder(), utf16_writer(), native_encoding != encoding);
  		}
  
  		if (encoding == encoding_utf32_be || encoding == encoding_utf32_le)
  		{
  			xml_encoding native_encoding = is_little_endian() ? encoding_utf32_le : encoding_utf32_be;
  
  			return convert_buffer_output_generic(r_u32, data, length, utf8_decoder(), utf32_writer(), native_encoding != encoding);
  		}
  
  		if (encoding == encoding_latin1)
  			return convert_buffer_output_generic(r_u8, data, length, utf8_decoder(), latin1_writer());
  
  		assert(false && "Invalid encoding"); // unreachable
  		return 0;
  	}
  #endif
  
  	class xml_buffered_writer
  	{
  		xml_buffered_writer(const xml_buffered_writer&);
  		xml_buffered_writer& operator=(const xml_buffered_writer&);
  
  	public:
  		xml_buffered_writer(xml_writer& writer_, xml_encoding user_encoding): writer(writer_), bufsize(0), encoding(get_write_encoding(user_encoding))
  		{
  			PUGI__STATIC_ASSERT(bufcapacity >= 8);
  		}
  
  		size_t flush()
  		{
  			flush(buffer, bufsize);
  			bufsize = 0;
  			return 0;
  		}
  
  		void flush(const char_t* data, size_t size)
  		{
  			if (size == 0) return;
  
  			// fast path, just write data
  			if (encoding == get_write_native_encoding())
  				writer.write(data, size * sizeof(char_t));
  			else
  			{
  				// convert chunk
  				size_t result = convert_buffer_output(scratch.data_char, scratch.data_u8, scratch.data_u16, scratch.data_u32, data, size, encoding);
  				assert(result <= sizeof(scratch));
  
  				// write data
  				writer.write(scratch.data_u8, result);
  			}
  		}
  
  		void write_direct(const char_t* data, size_t length)
  		{
  			// flush the remaining buffer contents
  			flush();
  
  			// handle large chunks
  			if (length > bufcapacity)
  			{
  				if (encoding == get_write_native_encoding())
  				{
  					// fast path, can just write data chunk
  					writer.write(data, length * sizeof(char_t));
  					return;
  				}
  
  				// need to convert in suitable chunks
  				while (length > bufcapacity)
  				{
  					// get chunk size by selecting such number of characters that are guaranteed to fit into scratch buffer
  					// and form a complete codepoint sequence (i.e. discard start of last codepoint if necessary)
  					size_t chunk_size = get_valid_length(data, bufcapacity);
  					assert(chunk_size);
  
  					// convert chunk and write
  					flush(data, chunk_size);
  
  					// iterate
  					data += chunk_size;
  					length -= chunk_size;
  				}
  
  				// small tail is copied below
  				bufsize = 0;
  			}
  
  			memcpy(buffer + bufsize, data, length * sizeof(char_t));
  			bufsize += length;
  		}
  
  		void write_buffer(const char_t* data, size_t length)
  		{
  			size_t offset = bufsize;
  
  			if (offset + length <= bufcapacity)
  			{
  				memcpy(buffer + offset, data, length * sizeof(char_t));
  				bufsize = offset + length;
  			}
  			else
  			{
  				write_direct(data, length);
  			}
  		}
  
  		void write_string(const char_t* data)
  		{
  			// write the part of the string that fits in the buffer
  			size_t offset = bufsize;
  
  			while (*data && offset < bufcapacity)
  				buffer[offset++] = *data++;
  
  			// write the rest
  			if (offset < bufcapacity)
  			{
  				bufsize = offset;
  			}
  			else
  			{
  				// backtrack a bit if we have split the codepoint
  				size_t length = offset - bufsize;
  				size_t extra = length - get_valid_length(data - length, length);
  
  				bufsize = offset - extra;
  
  				write_direct(data - extra, strlength(data) + extra);
  			}
  		}
  
  		void write(char_t d0)
  		{
  			size_t offset = bufsize;
  			if (offset > bufcapacity - 1) offset = flush();
  
  			buffer[offset + 0] = d0;
  			bufsize = offset + 1;
  		}
  
  		void write(char_t d0, char_t d1)
  		{
  			size_t offset = bufsize;
  			if (offset > bufcapacity - 2) offset = flush();
  
  			buffer[offset + 0] = d0;
  			buffer[offset + 1] = d1;
  			bufsize = offset + 2;
  		}
  
  		void write(char_t d0, char_t d1, char_t d2)
  		{
  			size_t offset = bufsize;
  			if (offset > bufcapacity - 3) offset = flush();
  
  			buffer[offset + 0] = d0;
  			buffer[offset + 1] = d1;
  			buffer[offset + 2] = d2;
  			bufsize = offset + 3;
  		}
  
  		void write(char_t d0, char_t d1, char_t d2, char_t d3)
  		{
  			size_t offset = bufsize;
  			if (offset > bufcapacity - 4) offset = flush();
  
  			buffer[offset + 0] = d0;
  			buffer[offset + 1] = d1;
  			buffer[offset + 2] = d2;
  			buffer[offset + 3] = d3;
  			bufsize = offset + 4;
  		}
  
  		void write(char_t d0, char_t d1, char_t d2, char_t d3, char_t d4)
  		{
  			size_t offset = bufsize;
  			if (offset > bufcapacity - 5) offset = flush();
  
  			buffer[offset + 0] = d0;
  			buffer[offset + 1] = d1;
  			buffer[offset + 2] = d2;
  			buffer[offset + 3] = d3;
  			buffer[offset + 4] = d4;
  			bufsize = offset + 5;
  		}
  
  		void write(char_t d0, char_t d1, char_t d2, char_t d3, char_t d4, char_t d5)
  		{
  			size_t offset = bufsize;
  			if (offset > bufcapacity - 6) offset = flush();
  
  			buffer[offset + 0] = d0;
  			buffer[offset + 1] = d1;
  			buffer[offset + 2] = d2;
  			buffer[offset + 3] = d3;
  			buffer[offset + 4] = d4;
  			buffer[offset + 5] = d5;
  			bufsize = offset + 6;
  		}
  
  		// utf8 maximum expansion: x4 (-> utf32)
  		// utf16 maximum expansion: x2 (-> utf32)
  		// utf32 maximum expansion: x1
  		enum
  		{
  			bufcapacitybytes =
  			#ifdef PUGIXML_MEMORY_OUTPUT_STACK
  				PUGIXML_MEMORY_OUTPUT_STACK
  			#else
  				10240
  			#endif
  			,
  			bufcapacity = bufcapacitybytes / (sizeof(char_t) + 4)
  		};
  
  		char_t buffer[bufcapacity];
  
  		union
  		{
  			uint8_t data_u8[4 * bufcapacity];
  			uint16_t data_u16[2 * bufcapacity];
  			uint32_t data_u32[bufcapacity];
  			char_t data_char[bufcapacity];
  		} scratch;
  
  		xml_writer& writer;
  		size_t bufsize;
  		xml_encoding encoding;
  	};
  
  	PUGI__FN void text_output_escaped(xml_buffered_writer& writer, const char_t* s, chartypex_t type)
  	{
  		while (*s)
  		{
  			const char_t* prev = s;
  
  			// While *s is a usual symbol
  			PUGI__SCANWHILE_UNROLL(!PUGI__IS_CHARTYPEX(ss, type));
  
  			writer.write_buffer(prev, static_cast<size_t>(s - prev));
  
  			switch (*s)
  			{
  				case 0: break;
  				case '&':
  					writer.write('&', 'a', 'm', 'p', ';');
  					++s;
  					break;
  				case '<':
  					writer.write('&', 'l', 't', ';');
  					++s;
  					break;
  				case '>':
  					writer.write('&', 'g', 't', ';');
  					++s;
  					break;
  				case '"':
  					writer.write('&', 'q', 'u', 'o', 't', ';');
  					++s;
  					break;
  				default: // s is not a usual symbol
  				{
  					unsigned int ch = static_cast<unsigned int>(*s++);
  					assert(ch < 32);
  
  					writer.write('&', '#', static_cast<char_t>((ch / 10) + '0'), static_cast<char_t>((ch % 10) + '0'), ';');
  				}
  			}
  		}
  	}
  
  	PUGI__FN void text_output(xml_buffered_writer& writer, const char_t* s, chartypex_t type, unsigned int flags)
  	{
  		if (flags & format_no_escapes)
  			writer.write_string(s);
  		else
  			text_output_escaped(writer, s, type);
  	}
  
  	PUGI__FN void text_output_cdata(xml_buffered_writer& writer, const char_t* s)
  	{
  		do
  		{
  			writer.write('<', '!', '[', 'C', 'D');
  			writer.write('A', 'T', 'A', '[');
  
  			const char_t* prev = s;
  
  			// look for ]]> sequence - we can't output it as is since it terminates CDATA
  			while (*s && !(s[0] == ']' && s[1] == ']' && s[2] == '>')) ++s;
  
  			// skip ]] if we stopped at ]]>, > will go to the next CDATA section
  			if (*s) s += 2;
  
  			writer.write_buffer(prev, static_cast<size_t>(s - prev));
  
  			writer.write(']', ']', '>');
  		}
  		while (*s);
  	}
  
  	PUGI__FN void text_output_indent(xml_buffered_writer& writer, const char_t* indent, size_t indent_length, unsigned int depth)
  	{
  		switch (indent_length)
  		{
  		case 1:
  		{
  			for (unsigned int i = 0; i < depth; ++i)
  				writer.write(indent[0]);
  			break;
  		}
  
  		case 2:
  		{
  			for (unsigned int i = 0; i < depth; ++i)
  				writer.write(indent[0], indent[1]);
  			break;
  		}
  
  		case 3:
  		{
  			for (unsigned int i = 0; i < depth; ++i)
  				writer.write(indent[0], indent[1], indent[2]);
  			break;
  		}
  
  		case 4:
  		{
  			for (unsigned int i = 0; i < depth; ++i)
  				writer.write(indent[0], indent[1], indent[2], indent[3]);
  			break;
  		}
  
  		default:
  		{
  			for (unsigned int i = 0; i < depth; ++i)
  				writer.write_buffer(indent, indent_length);
  		}
  		}
  	}
  
  	PUGI__FN void node_output_comment(xml_buffered_writer& writer, const char_t* s)
  	{
  		writer.write('<', '!', '-', '-');
  
  		while (*s)
  		{
  			const char_t* prev = s;
  
  			// look for -\0 or -- sequence - we can't output it since -- is illegal in comment body
  			while (*s && !(s[0] == '-' && (s[1] == '-' || s[1] == 0))) ++s;
  
  			writer.write_buffer(prev, static_cast<size_t>(s - prev));
  
  			if (*s)
  			{
  				assert(*s == '-');
  
  				writer.write('-', ' ');
  				++s;
  			}
  		}
  
  		writer.write('-', '-', '>');
  	}
  
  	PUGI__FN void node_output_pi_value(xml_buffered_writer& writer, const char_t* s)
  	{
  		while (*s)
  		{
  			const char_t* prev = s;
  
  			// look for ?> sequence - we can't output it since ?> terminates PI
  			while (*s && !(s[0] == '?' && s[1] == '>')) ++s;
  
  			writer.write_buffer(prev, static_cast<size_t>(s - prev));
  
  			if (*s)
  			{
  				assert(s[0] == '?' && s[1] == '>');
  
  				writer.write('?', ' ', '>');
  				s += 2;
  			}
  		}
  	}
  
  	PUGI__FN void node_output_attributes(xml_buffered_writer& writer, xml_node_struct* node, const char_t* indent, size_t indent_length, unsigned int flags, unsigned int depth)
  	{
  		const char_t* default_name = PUGIXML_TEXT(":anonymous");
  
  		for (xml_attribute_struct* a = node->first_attribute; a; a = a->next_attribute)
  		{
  			if ((flags & (format_indent_attributes | format_raw)) == format_indent_attributes)
  			{
  				writer.write('\n');
  
  				text_output_indent(writer, indent, indent_length, depth + 1);
  			}
  			else
  			{
  				writer.write(' ');
  			}
  
  			writer.write_string(a->name ? a->name + 0 : default_name);
  			writer.write('=', '"');
  
  			if (a->value)
  				text_output(writer, a->value, ctx_special_attr, flags);
  
  			writer.write('"');
  		}
  	}
  
  	PUGI__FN bool node_output_start(xml_buffered_writer& writer, xml_node_struct* node, const char_t* indent, size_t indent_length, unsigned int flags, unsigned int depth)
  	{
  		const char_t* default_name = PUGIXML_TEXT(":anonymous");
  		const char_t* name = node->name ? node->name + 0 : default_name;
  
  		writer.write('<');
  		writer.write_string(name);
  
  		if (node->first_attribute)
  			node_output_attributes(writer, node, indent, indent_length, flags, depth);
  
  		// element nodes can have value if parse_embed_pcdata was used
  		if (!node->value)
  		{
  			if (!node->first_child)
  			{
  				if (flags & format_no_empty_element_tags)
  				{
  					writer.write('>', '<', '/');
  					writer.write_string(name);
  					writer.write('>');
  
  					return false;
  				}
  				else
  				{
  					if ((flags & format_raw) == 0)
  						writer.write(' ');
  
  					writer.write('/', '>');
  
  					return false;
  				}
  			}
  			else
  			{
  				writer.write('>');
  
  				return true;
  			}
  		}
  		else
  		{
  			writer.write('>');
  
  			text_output(writer, node->value, ctx_special_pcdata, flags);
  
  			if (!node->first_child)
  			{
  				writer.write('<', '/');
  				writer.write_string(name);
  				writer.write('>');
  
  				return false;
  			}
  			else
  			{
  				return true;
  			}
  		}
  	}
  
  	PUGI__FN void node_output_end(xml_buffered_writer& writer, xml_node_struct* node)
  	{
  		const char_t* default_name = PUGIXML_TEXT(":anonymous");
  		const char_t* name = node->name ? node->name + 0 : default_name;
  
  		writer.write('<', '/');
  		writer.write_string(name);
  		writer.write('>');
  	}
  
  	PUGI__FN void node_output_simple(xml_buffered_writer& writer, xml_node_struct* node, unsigned int flags)
  	{
  		const char_t* default_name = PUGIXML_TEXT(":anonymous");
  
  		switch (PUGI__NODETYPE(node))
  		{
  			case node_pcdata:
  				text_output(writer, node->value ? node->value + 0 : PUGIXML_TEXT(""), ctx_special_pcdata, flags);
  				break;
  
  			case node_cdata:
  				text_output_cdata(writer, node->value ? node->value + 0 : PUGIXML_TEXT(""));
  				break;
  
  			case node_comment:
  				node_output_comment(writer, node->value ? node->value + 0 : PUGIXML_TEXT(""));
  				break;
  
  			case node_pi:
  				writer.write('<', '?');
  				writer.write_string(node->name ? node->name + 0 : default_name);
  
  				if (node->value)
  				{
  					writer.write(' ');
  					node_output_pi_value(writer, node->value);
  				}
  
  				writer.write('?', '>');
  				break;
  
  			case node_declaration:
  				writer.write('<', '?');
  				writer.write_string(node->name ? node->name + 0 : default_name);
  				node_output_attributes(writer, node, PUGIXML_TEXT(""), 0, flags | format_raw, 0);
  				writer.write('?', '>');
  				break;
  
  			case node_doctype:
  				writer.write('<', '!', 'D', 'O', 'C');
  				writer.write('T', 'Y', 'P', 'E');
  
  				if (node->value)
  				{
  					writer.write(' ');
  					writer.write_string(node->value);
  				}
  
  				writer.write('>');
  				break;
  
  			default:
  				assert(false && "Invalid node type"); // unreachable
  		}
  	}
  
  	enum indent_flags_t
  	{
  		indent_newline = 1,
  		indent_indent = 2
  	};
  
  	PUGI__FN void node_output(xml_buffered_writer& writer, xml_node_struct* root, const char_t* indent, unsigned int flags, unsigned int depth)
  	{
  		size_t indent_length = ((flags & (format_indent | format_indent_attributes)) && (flags & format_raw) == 0) ? strlength(indent) : 0;
  		unsigned int indent_flags = indent_indent;
  
  		xml_node_struct* node = root;
  
  		do
  		{
  			assert(node);
  
  			// begin writing current node
  			if (PUGI__NODETYPE(node) == node_pcdata || PUGI__NODETYPE(node) == node_cdata)
  			{
  				node_output_simple(writer, node, flags);
  
  				indent_flags = 0;
  			}
  			else
  			{
  				if ((indent_flags & indent_newline) && (flags & format_raw) == 0)
  					writer.write('\n');
  
  				if ((indent_flags & indent_indent) && indent_length)
  					text_output_indent(writer, indent, indent_length, depth);
  
  				if (PUGI__NODETYPE(node) == node_element)
  				{
  					indent_flags = indent_newline | indent_indent;
  
  					if (node_output_start(writer, node, indent, indent_length, flags, depth))
  					{
  						// element nodes can have value if parse_embed_pcdata was used
  						if (node->value)
  							indent_flags = 0;
  
  						node = node->first_child;
  						depth++;
  						continue;
  					}
  				}
  				else if (PUGI__NODETYPE(node) == node_document)
  				{
  					indent_flags = indent_indent;
  
  					if (node->first_child)
  					{
  						node = node->first_child;
  						continue;
  					}
  				}
  				else
  				{
  					node_output_simple(writer, node, flags);
  
  					indent_flags = indent_newline | indent_indent;
  				}
  			}
  
  			// continue to the next node
  			while (node != root)
  			{
  				if (node->next_sibling)
  				{
  					node = node->next_sibling;
  					break;
  				}
  
  				node = node->parent;
  
  				// write closing node
  				if (PUGI__NODETYPE(node) == node_element)
  				{
  					depth--;
  
  					if ((indent_flags & indent_newline) && (flags & format_raw) == 0)
  						writer.write('\n');
  
  					if ((indent_flags & indent_indent) && indent_length)
  						text_output_indent(writer, indent, indent_length, depth);
  
  					node_output_end(writer, node);
  
  					indent_flags = indent_newline | indent_indent;
  				}
  			}
  		}
  		while (node != root);
  
  		if ((indent_flags & indent_newline) && (flags & format_raw) == 0)
  			writer.write('\n');
  	}
  
  	PUGI__FN bool has_declaration(xml_node_struct* node)
  	{
  		for (xml_node_struct* child = node->first_child; child; child = child->next_sibling)
  		{
  			xml_node_type type = PUGI__NODETYPE(child);
  
  			if (type == node_declaration) return true;
  			if (type == node_element) return false;
  		}
  
  		return false;
  	}
  
  	PUGI__FN bool is_attribute_of(xml_attribute_struct* attr, xml_node_struct* node)
  	{
  		for (xml_attribute_struct* a = node->first_attribute; a; a = a->next_attribute)
  			if (a == attr)
  				return true;
  
  		return false;
  	}
  
  	PUGI__FN bool allow_insert_attribute(xml_node_type parent)
  	{
  		return parent == node_element || parent == node_declaration;
  	}
  
  	PUGI__FN bool allow_insert_child(xml_node_type parent, xml_node_type child)
  	{
  		if (parent != node_document && parent != node_element) return false;
  		if (child == node_document || child == node_null) return false;
  		if (parent != node_document && (child == node_declaration || child == node_doctype)) return false;
  
  		return true;
  	}
  
  	PUGI__FN bool allow_move(xml_node parent, xml_node child)
  	{
  		// check that child can be a child of parent
  		if (!allow_insert_child(parent.type(), child.type()))
  			return false;
  
  		// check that node is not moved between documents
  		if (parent.root() != child.root())
  			return false;
  
  		// check that new parent is not in the child subtree
  		xml_node cur = parent;
  
  		while (cur)
  		{
  			if (cur == child)
  				return false;
  
  			cur = cur.parent();
  		}
  
  		return true;
  	}
  
  	template <typename String, typename Header>
  	PUGI__FN void node_copy_string(String& dest, Header& header, uintptr_t header_mask, char_t* source, Header& source_header, xml_allocator* alloc)
  	{
  		assert(!dest && (header & header_mask) == 0);
  
  		if (source)
  		{
  			if (alloc && (source_header & header_mask) == 0)
  			{
  				dest = source;
  
  				// since strcpy_insitu can reuse document buffer memory we need to mark both source and dest as shared
  				header |= xml_memory_page_contents_shared_mask;
  				source_header |= xml_memory_page_contents_shared_mask;
  			}
  			else
  				strcpy_insitu(dest, header, header_mask, source, strlength(source));
  		}
  	}
  
  	PUGI__FN void node_copy_contents(xml_node_struct* dn, xml_node_struct* sn, xml_allocator* shared_alloc)
  	{
  		node_copy_string(dn->name, dn->header, xml_memory_page_name_allocated_mask, sn->name, sn->header, shared_alloc);
  		node_copy_string(dn->value, dn->header, xml_memory_page_value_allocated_mask, sn->value, sn->header, shared_alloc);
  
  		for (xml_attribute_struct* sa = sn->first_attribute; sa; sa = sa->next_attribute)
  		{
  			xml_attribute_struct* da = append_new_attribute(dn, get_allocator(dn));
  
  			if (da)
  			{
  				node_copy_string(da->name, da->header, xml_memory_page_name_allocated_mask, sa->name, sa->header, shared_alloc);
  				node_copy_string(da->value, da->header, xml_memory_page_value_allocated_mask, sa->value, sa->header, shared_alloc);
  			}
  		}
  	}
  
  	PUGI__FN void node_copy_tree(xml_node_struct* dn, xml_node_struct* sn)
  	{
  		xml_allocator& alloc = get_allocator(dn);
  		xml_allocator* shared_alloc = (&alloc == &get_allocator(sn)) ? &alloc : 0;
  
  		node_copy_contents(dn, sn, shared_alloc);
  
  		xml_node_struct* dit = dn;
  		xml_node_struct* sit = sn->first_child;
  
  		while (sit && sit != sn)
  		{
  			if (sit != dn)
  			{
  				xml_node_struct* copy = append_new_node(dit, alloc, PUGI__NODETYPE(sit));
  
  				if (copy)
  				{
  					node_copy_contents(copy, sit, shared_alloc);
  
  					if (sit->first_child)
  					{
  						dit = copy;
  						sit = sit->first_child;
  						continue;
  					}
  				}
  			}
  
  			// continue to the next node
  			do
  			{
  				if (sit->next_sibling)
  				{
  					sit = sit->next_sibling;
  					break;
  				}
  
  				sit = sit->parent;
  				dit = dit->parent;
  			}
  			while (sit != sn);
  		}
  	}
  
  	PUGI__FN void node_copy_attribute(xml_attribute_struct* da, xml_attribute_struct* sa)
  	{
  		xml_allocator& alloc = get_allocator(da);
  		xml_allocator* shared_alloc = (&alloc == &get_allocator(sa)) ? &alloc : 0;
  
  		node_copy_string(da->name, da->header, xml_memory_page_name_allocated_mask, sa->name, sa->header, shared_alloc);
  		node_copy_string(da->value, da->header, xml_memory_page_value_allocated_mask, sa->value, sa->header, shared_alloc);
  	}
  
  	inline bool is_text_node(xml_node_struct* node)
  	{
  		xml_node_type type = PUGI__NODETYPE(node);
  
  		return type == node_pcdata || type == node_cdata;
  	}
  
  	// get value with conversion functions
  	template <typename U> PUGI__FN PUGI__UNSIGNED_OVERFLOW U string_to_integer(const char_t* value, U minv, U maxv)
  	{
  		U result = 0;
  		const char_t* s = value;
  
  		while (PUGI__IS_CHARTYPE(*s, ct_space))
  			s++;
  
  		bool negative = (*s == '-');
  
  		s += (*s == '+' || *s == '-');
  
  		bool overflow = false;
  
  		if (s[0] == '0' && (s[1] | ' ') == 'x')
  		{
  			s += 2;
  
  			// since overflow detection relies on length of the sequence skip leading zeros
  			while (*s == '0')
  				s++;
  
  			const char_t* start = s;
  
  			for (;;)
  			{
  				if (static_cast<unsigned>(*s - '0') < 10)
  					result = result * 16 + (*s - '0');
  				else if (static_cast<unsigned>((*s | ' ') - 'a') < 6)
  					result = result * 16 + ((*s | ' ') - 'a' + 10);
  				else
  					break;
  
  				s++;
  			}
  
  			size_t digits = static_cast<size_t>(s - start);
  
  			overflow = digits > sizeof(U) * 2;
  		}
  		else
  		{
  			// since overflow detection relies on length of the sequence skip leading zeros
  			while (*s == '0')
  				s++;
  
  			const char_t* start = s;
  
  			for (;;)
  			{
  				if (static_cast<unsigned>(*s - '0') < 10)
  					result = result * 10 + (*s - '0');
  				else
  					break;
  
  				s++;
  			}
  
  			size_t digits = static_cast<size_t>(s - start);
  
  			PUGI__STATIC_ASSERT(sizeof(U) == 8 || sizeof(U) == 4 || sizeof(U) == 2);
  
  			const size_t max_digits10 = sizeof(U) == 8 ? 20 : sizeof(U) == 4 ? 10 : 5;
  			const char_t max_lead = sizeof(U) == 8 ? '1' : sizeof(U) == 4 ? '4' : '6';
  			const size_t high_bit = sizeof(U) * 8 - 1;
  
  			overflow = digits >= max_digits10 && !(digits == max_digits10 && (*start < max_lead || (*start == max_lead && result >> high_bit)));
  		}
  
  		if (negative)
  		{
  			// Workaround for crayc++ CC-3059: Expected no overflow in routine.
  		#ifdef _CRAYC
  			return (overflow || result > ~minv + 1) ? minv : ~result + 1;
  		#else
  			return (overflow || result > 0 - minv) ? minv : 0 - result;
  		#endif
  		}
  		else
  			return (overflow || result > maxv) ? maxv : result;
  	}
  
  	PUGI__FN int get_value_int(const char_t* value)
  	{
  		return string_to_integer<unsigned int>(value, static_cast<unsigned int>(INT_MIN), INT_MAX);
  	}
  
  	PUGI__FN unsigned int get_value_uint(const char_t* value)
  	{
  		return string_to_integer<unsigned int>(value, 0, UINT_MAX);
  	}
  
  	PUGI__FN double get_value_double(const char_t* value)
  	{
  	#ifdef PUGIXML_WCHAR_MODE
  		return wcstod(value, 0);
  	#else
  		return strtod(value, 0);
  	#endif
  	}
  
  	PUGI__FN float get_value_float(const char_t* value)
  	{
  	#ifdef PUGIXML_WCHAR_MODE
  		return static_cast<float>(wcstod(value, 0));
  	#else
  		return static_cast<float>(strtod(value, 0));
  	#endif
  	}
  
  	PUGI__FN bool get_value_bool(const char_t* value)
  	{
  		// only look at first char
  		char_t first = *value;
  
  		// 1*, t* (true), T* (True), y* (yes), Y* (YES)
  		return (first == '1' || first == 't' || first == 'T' || first == 'y' || first == 'Y');
  	}
  
  #ifdef PUGIXML_HAS_LONG_LONG
  	PUGI__FN long long get_value_llong(const char_t* value)
  	{
  		return string_to_integer<unsigned long long>(value, static_cast<unsigned long long>(LLONG_MIN), LLONG_MAX);
  	}
  
  	PUGI__FN unsigned long long get_value_ullong(const char_t* value)
  	{
  		return string_to_integer<unsigned long long>(value, 0, ULLONG_MAX);
  	}
  #endif
  
  	template <typename U> PUGI__FN PUGI__UNSIGNED_OVERFLOW char_t* integer_to_string(char_t* begin, char_t* end, U value, bool negative)
  	{
  		char_t* result = end - 1;
  		U rest = negative ? 0 - value : value;
  
  		do
  		{
  			*result-- = static_cast<char_t>('0' + (rest % 10));
  			rest /= 10;
  		}
  		while (rest);
  
  		assert(result >= begin);
  		(void)begin;
  
  		*result = '-';
  
  		return result + !negative;
  	}
  
  	// set value with conversion functions
  	template <typename String, typename Header>
  	PUGI__FN bool set_value_ascii(String& dest, Header& header, uintptr_t header_mask, char* buf)
  	{
  	#ifdef PUGIXML_WCHAR_MODE
  		char_t wbuf[128];
  		assert(strlen(buf) < sizeof(wbuf) / sizeof(wbuf[0]));
  
  		size_t offset = 0;
  		for (; buf[offset]; ++offset) wbuf[offset] = buf[offset];
  
  		return strcpy_insitu(dest, header, header_mask, wbuf, offset);
  	#else
  		return strcpy_insitu(dest, header, header_mask, buf, strlen(buf));
  	#endif
  	}
  
  	template <typename U, typename String, typename Header>
  	PUGI__FN bool set_value_integer(String& dest, Header& header, uintptr_t header_mask, U value, bool negative)
  	{
  		char_t buf[64];
  		char_t* end = buf + sizeof(buf) / sizeof(buf[0]);
  		char_t* begin = integer_to_string(buf, end, value, negative);
  
  		return strcpy_insitu(dest, header, header_mask, begin, end - begin);
  	}
  
  	template <typename String, typename Header>
  	PUGI__FN bool set_value_convert(String& dest, Header& header, uintptr_t header_mask, float value)
  	{
  		char buf[128];
  		PUGI__SNPRINTF(buf, "%.9g", value);
  
  		return set_value_ascii(dest, header, header_mask, buf);
  	}
  
  	template <typename String, typename Header>
  	PUGI__FN bool set_value_convert(String& dest, Header& header, uintptr_t header_mask, double value)
  	{
  		char buf[128];
  		PUGI__SNPRINTF(buf, "%.17g", value);
  
  		return set_value_ascii(dest, header, header_mask, buf);
  	}
  
  	template <typename String, typename Header>
  	PUGI__FN bool set_value_bool(String& dest, Header& header, uintptr_t header_mask, bool value)
  	{
  		return strcpy_insitu(dest, header, header_mask, value ? PUGIXML_TEXT("true") : PUGIXML_TEXT("false"), value ? 4 : 5);
  	}
  
  	PUGI__FN xml_parse_result load_buffer_impl(xml_document_struct* doc, xml_node_struct* root, void* contents, size_t size, unsigned int options, xml_encoding encoding, bool is_mutable, bool own, char_t** out_buffer)
  	{
  		// check input buffer
  		if (!contents && size) return make_parse_result(status_io_error);
  
  		// get actual encoding
  		xml_encoding buffer_encoding = impl::get_buffer_encoding(encoding, contents, size);
  
  		// get private buffer
  		char_t* buffer = 0;
  		size_t length = 0;
  
  		if (!impl::convert_buffer(buffer, length, buffer_encoding, contents, size, is_mutable)) return impl::make_parse_result(status_out_of_memory);
  
  		// delete original buffer if we performed a conversion
  		if (own && buffer != contents && contents) impl::xml_memory::deallocate(contents);
  
  		// grab onto buffer if it's our buffer, user is responsible for deallocating contents himself
  		if (own || buffer != contents) *out_buffer = buffer;
  
  		// store buffer for offset_debug
  		doc->buffer = buffer;
  
  		// parse
  		xml_parse_result res = impl::xml_parser::parse(buffer, length, doc, root, options);
  
  		// remember encoding
  		res.encoding = buffer_encoding;
  
  		return res;
  	}
  
  	// we need to get length of entire file to load it in memory; the only (relatively) sane way to do it is via seek/tell trick
  	PUGI__FN xml_parse_status get_file_size(FILE* file, size_t& out_result)
  	{
  	#if defined(PUGI__MSVC_CRT_VERSION) && PUGI__MSVC_CRT_VERSION >= 1400 && !defined(_WIN32_WCE)
  		// there are 64-bit versions of fseek/ftell, let's use them
  		typedef __int64 length_type;
  
  		_fseeki64(file, 0, SEEK_END);
  		length_type length = _ftelli64(file);
  		_fseeki64(file, 0, SEEK_SET);
  	#elif defined(__MINGW32__) && !defined(__NO_MINGW_LFS) && (!defined(__STRICT_ANSI__) || defined(__MINGW64_VERSION_MAJOR))
  		// there are 64-bit versions of fseek/ftell, let's use them
  		typedef off64_t length_type;
  
  		fseeko64(file, 0, SEEK_END);
  		length_type length = ftello64(file);
  		fseeko64(file, 0, SEEK_SET);
  	#else
  		// if this is a 32-bit OS, long is enough; if this is a unix system, long is 64-bit, which is enough; otherwise we can't do anything anyway.
  		typedef long length_type;
  
  		fseek(file, 0, SEEK_END);
  		length_type length = ftell(file);
  		fseek(file, 0, SEEK_SET);
  	#endif
  
  		// check for I/O errors
  		if (length < 0) return status_io_error;
  
  		// check for overflow
  		size_t result = static_cast<size_t>(length);
  
  		if (static_cast<length_type>(result) != length) return status_out_of_memory;
  
  		// finalize
  		out_result = result;
  
  		return status_ok;
  	}
  
  	// This function assumes that buffer has extra sizeof(char_t) writable bytes after size
  	PUGI__FN size_t zero_terminate_buffer(void* buffer, size_t size, xml_encoding encoding)
  	{
  		// We only need to zero-terminate if encoding conversion does not do it for us
  	#ifdef PUGIXML_WCHAR_MODE
  		xml_encoding wchar_encoding = get_wchar_encoding();
  
  		if (encoding == wchar_encoding || need_endian_swap_utf(encoding, wchar_encoding))
  		{
  			size_t length = size / sizeof(char_t);
  
  			static_cast<char_t*>(buffer)[length] = 0;
  			return (length + 1) * sizeof(char_t);
  		}
  	#else
  		if (encoding == encoding_utf8)
  		{
  			static_cast<char*>(buffer)[size] = 0;
  			return size + 1;
  		}
  	#endif
  
  		return size;
  	}
  
  	PUGI__FN xml_parse_result load_file_impl(xml_document_struct* doc, FILE* file, unsigned int options, xml_encoding encoding, char_t** out_buffer)
  	{
  		if (!file) return make_parse_result(status_file_not_found);
  
  		// get file size (can result in I/O errors)
  		size_t size = 0;
  		xml_parse_status size_status = get_file_size(file, size);
  		if (size_status != status_ok) return make_parse_result(size_status);
  
  		size_t max_suffix_size = sizeof(char_t);
  
  		// allocate buffer for the whole file
  		char* contents = static_cast<char*>(xml_memory::allocate(size + max_suffix_size));
  		if (!contents) return make_parse_result(status_out_of_memory);
  
  		// read file in memory
  		size_t read_size = fread(contents, 1, size, file);
  
  		if (read_size != size)
  		{
  			xml_memory::deallocate(contents);
  			return make_parse_result(status_io_error);
  		}
  
  		xml_encoding real_encoding = get_buffer_encoding(encoding, contents, size);
  
  		return load_buffer_impl(doc, doc, contents, zero_terminate_buffer(contents, size, real_encoding), options, real_encoding, true, true, out_buffer);
  	}
  
  	PUGI__FN void close_file(FILE* file)
  	{
  		fclose(file);
  	}
  
  #ifndef PUGIXML_NO_STL
  	template <typename T> struct xml_stream_chunk
  	{
  		static xml_stream_chunk* create()
  		{
  			void* memory = xml_memory::allocate(sizeof(xml_stream_chunk));
  			if (!memory) return 0;
  
  			return new (memory) xml_stream_chunk();
  		}
  
  		static void destroy(xml_stream_chunk* chunk)
  		{
  			// free chunk chain
  			while (chunk)
  			{
  				xml_stream_chunk* next_ = chunk->next;
  
  				xml_memory::deallocate(chunk);
  
  				chunk = next_;
  			}
  		}
  
  		xml_stream_chunk(): next(0), size(0)
  		{
  		}
  
  		xml_stream_chunk* next;
  		size_t size;
  
  		T data[xml_memory_page_size / sizeof(T)];
  	};
  
  	template <typename T> PUGI__FN xml_parse_status load_stream_data_noseek(std::basic_istream<T>& stream, void** out_buffer, size_t* out_size)
  	{
  		auto_deleter<xml_stream_chunk<T> > chunks(0, xml_stream_chunk<T>::destroy);
  
  		// read file to a chunk list
  		size_t total = 0;
  		xml_stream_chunk<T>* last = 0;
  
  		while (!stream.eof())
  		{
  			// allocate new chunk
  			xml_stream_chunk<T>* chunk = xml_stream_chunk<T>::create();
  			if (!chunk) return status_out_of_memory;
  
  			// append chunk to list
  			if (last) last = last->next = chunk;
  			else chunks.data = last = chunk;
  
  			// read data to chunk
  			stream.read(chunk->data, static_cast<std::streamsize>(sizeof(chunk->data) / sizeof(T)));
  			chunk->size = static_cast<size_t>(stream.gcount()) * sizeof(T);
  
  			// read may set failbit | eofbit in case gcount() is less than read length, so check for other I/O errors
  			if (stream.bad() || (!stream.eof() && stream.fail())) return status_io_error;
  
  			// guard against huge files (chunk size is small enough to make this overflow check work)
  			if (total + chunk->size < total) return status_out_of_memory;
  			total += chunk->size;
  		}
  
  		size_t max_suffix_size = sizeof(char_t);
  
  		// copy chunk list to a contiguous buffer
  		char* buffer = static_cast<char*>(xml_memory::allocate(total + max_suffix_size));
  		if (!buffer) return status_out_of_memory;
  
  		char* write = buffer;
  
  		for (xml_stream_chunk<T>* chunk = chunks.data; chunk; chunk = chunk->next)
  		{
  			assert(write + chunk->size <= buffer + total);
  			memcpy(write, chunk->data, chunk->size);
  			write += chunk->size;
  		}
  
  		assert(write == buffer + total);
  
  		// return buffer
  		*out_buffer = buffer;
  		*out_size = total;
  
  		return status_ok;
  	}
  
  	template <typename T> PUGI__FN xml_parse_status load_stream_data_seek(std::basic_istream<T>& stream, void** out_buffer, size_t* out_size)
  	{
  		// get length of remaining data in stream
  		typename std::basic_istream<T>::pos_type pos = stream.tellg();
  		stream.seekg(0, std::ios::end);
  		std::streamoff length = stream.tellg() - pos;
  		stream.seekg(pos);
  
  		if (stream.fail() || pos < 0) return status_io_error;
  
  		// guard against huge files
  		size_t read_length = static_cast<size_t>(length);
  
  		if (static_cast<std::streamsize>(read_length) != length || length < 0) return status_out_of_memory;
  
  		size_t max_suffix_size = sizeof(char_t);
  
  		// read stream data into memory (guard against stream exceptions with buffer holder)
  		auto_deleter<void> buffer(xml_memory::allocate(read_length * sizeof(T) + max_suffix_size), xml_memory::deallocate);
  		if (!buffer.data) return status_out_of_memory;
  
  		stream.read(static_cast<T*>(buffer.data), static_cast<std::streamsize>(read_length));
  
  		// read may set failbit | eofbit in case gcount() is less than read_length (i.e. line ending conversion), so check for other I/O errors
  		if (stream.bad() || (!stream.eof() && stream.fail())) return status_io_error;
  
  		// return buffer
  		size_t actual_length = static_cast<size_t>(stream.gcount());
  		assert(actual_length <= read_length);
  
  		*out_buffer = buffer.release();
  		*out_size = actual_length * sizeof(T);
  
  		return status_ok;
  	}
  
  	template <typename T> PUGI__FN xml_parse_result load_stream_impl(xml_document_struct* doc, std::basic_istream<T>& stream, unsigned int options, xml_encoding encoding, char_t** out_buffer)
  	{
  		void* buffer = 0;
  		size_t size = 0;
  		xml_parse_status status = status_ok;
  
  		// if stream has an error bit set, bail out (otherwise tellg() can fail and we'll clear error bits)
  		if (stream.fail()) return make_parse_result(status_io_error);
  
  		// load stream to memory (using seek-based implementation if possible, since it's faster and takes less memory)
  		if (stream.tellg() < 0)
  		{
  			stream.clear(); // clear error flags that could be set by a failing tellg
  			status = load_stream_data_noseek(stream, &buffer, &size);
  		}
  		else
  			status = load_stream_data_seek(stream, &buffer, &size);
  
  		if (status != status_ok) return make_parse_result(status);
  
  		xml_encoding real_encoding = get_buffer_encoding(encoding, buffer, size);
  
  		return load_buffer_impl(doc, doc, buffer, zero_terminate_buffer(buffer, size, real_encoding), options, real_encoding, true, true, out_buffer);
  	}
  #endif
  
  #if defined(PUGI__MSVC_CRT_VERSION) || defined(__BORLANDC__) || (defined(__MINGW32__) && (!defined(__STRICT_ANSI__) || defined(__MINGW64_VERSION_MAJOR)))
  	PUGI__FN FILE* open_file_wide(const wchar_t* path, const wchar_t* mode)
  	{
  		return _wfopen(path, mode);
  	}
  #else
  	PUGI__FN char* convert_path_heap(const wchar_t* str)
  	{
  		assert(str);
  
  		// first pass: get length in utf8 characters
  		size_t length = strlength_wide(str);
  		size_t size = as_utf8_begin(str, length);
  
  		// allocate resulting string
  		char* result = static_cast<char*>(xml_memory::allocate(size + 1));
  		if (!result) return 0;
  
  		// second pass: convert to utf8
  		as_utf8_end(result, size, str, length);
  
  		// zero-terminate
  		result[size] = 0;
  
  		return result;
  	}
  
  	PUGI__FN FILE* open_file_wide(const wchar_t* path, const wchar_t* mode)
  	{
  		// there is no standard function to open wide paths, so our best bet is to try utf8 path
  		char* path_utf8 = convert_path_heap(path);
  		if (!path_utf8) return 0;
  
  		// convert mode to ASCII (we mirror _wfopen interface)
  		char mode_ascii[4] = {0};
  		for (size_t i = 0; mode[i]; ++i) mode_ascii[i] = static_cast<char>(mode[i]);
  
  		// try to open the utf8 path
  		FILE* result = fopen(path_utf8, mode_ascii);
  
  		// free dummy buffer
  		xml_memory::deallocate(path_utf8);
  
  		return result;
  	}
  #endif
  
  	PUGI__FN bool save_file_impl(const xml_document& doc, FILE* file, const char_t* indent, unsigned int flags, xml_encoding encoding)
  	{
  		if (!file) return false;
  
  		xml_writer_file writer(file);
  		doc.save(writer, indent, flags, encoding);
  
  		return ferror(file) == 0;
  	}
  
  	struct name_null_sentry
  	{
  		xml_node_struct* node;
  		char_t* name;
  
  		name_null_sentry(xml_node_struct* node_): node(node_), name(node_->name)
  		{
  			node->name = 0;
  		}
  
  		~name_null_sentry()
  		{
  			node->name = name;
  		}
  	};
  PUGI__NS_END
  
  namespace pugi
  {
  	PUGI__FN xml_writer_file::xml_writer_file(void* file_): file(file_)
  	{
  	}
  
  	PUGI__FN void xml_writer_file::write(const void* data, size_t size)
  	{
  		size_t result = fwrite(data, 1, size, static_cast<FILE*>(file));
  		(void)!result; // unfortunately we can't do proper error handling here
  	}
  
  #ifndef PUGIXML_NO_STL
  	PUGI__FN xml_writer_stream::xml_writer_stream(std::basic_ostream<char, std::char_traits<char> >& stream): narrow_stream(&stream), wide_stream(0)
  	{
  	}
  
  	PUGI__FN xml_writer_stream::xml_writer_stream(std::basic_ostream<wchar_t, std::char_traits<wchar_t> >& stream): narrow_stream(0), wide_stream(&stream)
  	{
  	}
  
  	PUGI__FN void xml_writer_stream::write(const void* data, size_t size)
  	{
  		if (narrow_stream)
  		{
  			assert(!wide_stream);
  			narrow_stream->write(reinterpret_cast<const char*>(data), static_cast<std::streamsize>(size));
  		}
  		else
  		{
  			assert(wide_stream);
  			assert(size % sizeof(wchar_t) == 0);
  
  			wide_stream->write(reinterpret_cast<const wchar_t*>(data), static_cast<std::streamsize>(size / sizeof(wchar_t)));
  		}
  	}
  #endif
  
  	PUGI__FN xml_tree_walker::xml_tree_walker(): _depth(0)
  	{
  	}
  
  	PUGI__FN xml_tree_walker::~xml_tree_walker()
  	{
  	}
  
  	PUGI__FN int xml_tree_walker::depth() const
  	{
  		return _depth;
  	}
  
  	PUGI__FN bool xml_tree_walker::begin(xml_node&)
  	{
  		return true;
  	}
  
  	PUGI__FN bool xml_tree_walker::end(xml_node&)
  	{
  		return true;
  	}
  
  	PUGI__FN xml_attribute::xml_attribute(): _attr(0)
  	{
  	}
  
  	PUGI__FN xml_attribute::xml_attribute(xml_attribute_struct* attr): _attr(attr)
  	{
  	}
  
  	PUGI__FN static void unspecified_bool_xml_attribute(xml_attribute***)
  	{
  	}
  
  	PUGI__FN xml_attribute::operator xml_attribute::unspecified_bool_type() const
  	{
  		return _attr ? unspecified_bool_xml_attribute : 0;
  	}
  
  	PUGI__FN bool xml_attribute::operator!() const
  	{
  		return !_attr;
  	}
  
  	PUGI__FN bool xml_attribute::operator==(const xml_attribute& r) const
  	{
  		return (_attr == r._attr);
  	}
  
  	PUGI__FN bool xml_attribute::operator!=(const xml_attribute& r) const
  	{
  		return (_attr != r._attr);
  	}
  
  	PUGI__FN bool xml_attribute::operator<(const xml_attribute& r) const
  	{
  		return (_attr < r._attr);
  	}
  
  	PUGI__FN bool xml_attribute::operator>(const xml_attribute& r) const
  	{
  		return (_attr > r._attr);
  	}
  
  	PUGI__FN bool xml_attribute::operator<=(const xml_attribute& r) const
  	{
  		return (_attr <= r._attr);
  	}
  
  	PUGI__FN bool xml_attribute::operator>=(const xml_attribute& r) const
  	{
  		return (_attr >= r._attr);
  	}
  
  	PUGI__FN xml_attribute xml_attribute::next_attribute() const
  	{
  		return _attr ? xml_attribute(_attr->next_attribute) : xml_attribute();
  	}
  
  	PUGI__FN xml_attribute xml_attribute::previous_attribute() const
  	{
  		return _attr && _attr->prev_attribute_c->next_attribute ? xml_attribute(_attr->prev_attribute_c) : xml_attribute();
  	}
  
  	PUGI__FN const char_t* xml_attribute::as_string(const char_t* def) const
  	{
  		return (_attr && _attr->value) ? _attr->value + 0 : def;
  	}
  
  	PUGI__FN int xml_attribute::as_int(int def) const
  	{
  		return (_attr && _attr->value) ? impl::get_value_int(_attr->value) : def;
  	}
  
  	PUGI__FN unsigned int xml_attribute::as_uint(unsigned int def) const
  	{
  		return (_attr && _attr->value) ? impl::get_value_uint(_attr->value) : def;
  	}
  
  	PUGI__FN double xml_attribute::as_double(double def) const
  	{
  		return (_attr && _attr->value) ? impl::get_value_double(_attr->value) : def;
  	}
  
  	PUGI__FN float xml_attribute::as_float(float def) const
  	{
  		return (_attr && _attr->value) ? impl::get_value_float(_attr->value) : def;
  	}
  
  	PUGI__FN bool xml_attribute::as_bool(bool def) const
  	{
  		return (_attr && _attr->value) ? impl::get_value_bool(_attr->value) : def;
  	}
  
  #ifdef PUGIXML_HAS_LONG_LONG
  	PUGI__FN long long xml_attribute::as_llong(long long def) const
  	{
  		return (_attr && _attr->value) ? impl::get_value_llong(_attr->value) : def;
  	}
  
  	PUGI__FN unsigned long long xml_attribute::as_ullong(unsigned long long def) const
  	{
  		return (_attr && _attr->value) ? impl::get_value_ullong(_attr->value) : def;
  	}
  #endif
  
  	PUGI__FN bool xml_attribute::empty() const
  	{
  		return !_attr;
  	}
  
  	PUGI__FN const char_t* xml_attribute::name() const
  	{
  		return (_attr && _attr->name) ? _attr->name + 0 : PUGIXML_TEXT("");
  	}
  
  	PUGI__FN const char_t* xml_attribute::value() const
  	{
  		return (_attr && _attr->value) ? _attr->value + 0 : PUGIXML_TEXT("");
  	}
  
  	PUGI__FN size_t xml_attribute::hash_value() const
  	{
  		return static_cast<size_t>(reinterpret_cast<uintptr_t>(_attr) / sizeof(xml_attribute_struct));
  	}
  
  	PUGI__FN xml_attribute_struct* xml_attribute::internal_object() const
  	{
  		return _attr;
  	}
  
  	PUGI__FN xml_attribute& xml_attribute::operator=(const char_t* rhs)
  	{
  		set_value(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_attribute& xml_attribute::operator=(int rhs)
  	{
  		set_value(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_attribute& xml_attribute::operator=(unsigned int rhs)
  	{
  		set_value(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_attribute& xml_attribute::operator=(long rhs)
  	{
  		set_value(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_attribute& xml_attribute::operator=(unsigned long rhs)
  	{
  		set_value(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_attribute& xml_attribute::operator=(double rhs)
  	{
  		set_value(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_attribute& xml_attribute::operator=(float rhs)
  	{
  		set_value(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_attribute& xml_attribute::operator=(bool rhs)
  	{
  		set_value(rhs);
  		return *this;
  	}
  
  #ifdef PUGIXML_HAS_LONG_LONG
  	PUGI__FN xml_attribute& xml_attribute::operator=(long long rhs)
  	{
  		set_value(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_attribute& xml_attribute::operator=(unsigned long long rhs)
  	{
  		set_value(rhs);
  		return *this;
  	}
  #endif
  
  	PUGI__FN bool xml_attribute::set_name(const char_t* rhs)
  	{
  		if (!_attr) return false;
  
  		return impl::strcpy_insitu(_attr->name, _attr->header, impl::xml_memory_page_name_allocated_mask, rhs, impl::strlength(rhs));
  	}
  
  	PUGI__FN bool xml_attribute::set_value(const char_t* rhs)
  	{
  		if (!_attr) return false;
  
  		return impl::strcpy_insitu(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, impl::strlength(rhs));
  	}
  
  	PUGI__FN bool xml_attribute::set_value(int rhs)
  	{
  		if (!_attr) return false;
  
  		return impl::set_value_integer<unsigned int>(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, rhs < 0);
  	}
  
  	PUGI__FN bool xml_attribute::set_value(unsigned int rhs)
  	{
  		if (!_attr) return false;
  
  		return impl::set_value_integer<unsigned int>(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, false);
  	}
  
  	PUGI__FN bool xml_attribute::set_value(long rhs)
  	{
  		if (!_attr) return false;
  
  		return impl::set_value_integer<unsigned long>(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, rhs < 0);
  	}
  
  	PUGI__FN bool xml_attribute::set_value(unsigned long rhs)
  	{
  		if (!_attr) return false;
  
  		return impl::set_value_integer<unsigned long>(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, false);
  	}
  
  	PUGI__FN bool xml_attribute::set_value(double rhs)
  	{
  		if (!_attr) return false;
  
  		return impl::set_value_convert(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs);
  	}
  
  	PUGI__FN bool xml_attribute::set_value(float rhs)
  	{
  		if (!_attr) return false;
  
  		return impl::set_value_convert(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs);
  	}
  
  	PUGI__FN bool xml_attribute::set_value(bool rhs)
  	{
  		if (!_attr) return false;
  
  		return impl::set_value_bool(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs);
  	}
  
  #ifdef PUGIXML_HAS_LONG_LONG
  	PUGI__FN bool xml_attribute::set_value(long long rhs)
  	{
  		if (!_attr) return false;
  
  		return impl::set_value_integer<unsigned long long>(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, rhs < 0);
  	}
  
  	PUGI__FN bool xml_attribute::set_value(unsigned long long rhs)
  	{
  		if (!_attr) return false;
  
  		return impl::set_value_integer<unsigned long long>(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, false);
  	}
  #endif
  
  #ifdef __BORLANDC__
  	PUGI__FN bool operator&&(const xml_attribute& lhs, bool rhs)
  	{
  		return (bool)lhs && rhs;
  	}
  
  	PUGI__FN bool operator||(const xml_attribute& lhs, bool rhs)
  	{
  		return (bool)lhs || rhs;
  	}
  #endif
  
  	PUGI__FN xml_node::xml_node(): _root(0)
  	{
  	}
  
  	PUGI__FN xml_node::xml_node(xml_node_struct* p): _root(p)
  	{
  	}
  
  	PUGI__FN static void unspecified_bool_xml_node(xml_node***)
  	{
  	}
  
  	PUGI__FN xml_node::operator xml_node::unspecified_bool_type() const
  	{
  		return _root ? unspecified_bool_xml_node : 0;
  	}
  
  	PUGI__FN bool xml_node::operator!() const
  	{
  		return !_root;
  	}
  
  	PUGI__FN xml_node::iterator xml_node::begin() const
  	{
  		return iterator(_root ? _root->first_child + 0 : 0, _root);
  	}
  
  	PUGI__FN xml_node::iterator xml_node::end() const
  	{
  		return iterator(0, _root);
  	}
  
  	PUGI__FN xml_node::attribute_iterator xml_node::attributes_begin() const
  	{
  		return attribute_iterator(_root ? _root->first_attribute + 0 : 0, _root);
  	}
  
  	PUGI__FN xml_node::attribute_iterator xml_node::attributes_end() const
  	{
  		return attribute_iterator(0, _root);
  	}
  
  	PUGI__FN xml_object_range<xml_node_iterator> xml_node::children() const
  	{
  		return xml_object_range<xml_node_iterator>(begin(), end());
  	}
  
  	PUGI__FN xml_object_range<xml_named_node_iterator> xml_node::children(const char_t* name_) const
  	{
  		return xml_object_range<xml_named_node_iterator>(xml_named_node_iterator(child(name_)._root, _root, name_), xml_named_node_iterator(0, _root, name_));
  	}
  
  	PUGI__FN xml_object_range<xml_attribute_iterator> xml_node::attributes() const
  	{
  		return xml_object_range<xml_attribute_iterator>(attributes_begin(), attributes_end());
  	}
  
  	PUGI__FN bool xml_node::operator==(const xml_node& r) const
  	{
  		return (_root == r._root);
  	}
  
  	PUGI__FN bool xml_node::operator!=(const xml_node& r) const
  	{
  		return (_root != r._root);
  	}
  
  	PUGI__FN bool xml_node::operator<(const xml_node& r) const
  	{
  		return (_root < r._root);
  	}
  
  	PUGI__FN bool xml_node::operator>(const xml_node& r) const
  	{
  		return (_root > r._root);
  	}
  
  	PUGI__FN bool xml_node::operator<=(const xml_node& r) const
  	{
  		return (_root <= r._root);
  	}
  
  	PUGI__FN bool xml_node::operator>=(const xml_node& r) const
  	{
  		return (_root >= r._root);
  	}
  
  	PUGI__FN bool xml_node::empty() const
  	{
  		return !_root;
  	}
  
  	PUGI__FN const char_t* xml_node::name() const
  	{
  		return (_root && _root->name) ? _root->name + 0 : PUGIXML_TEXT("");
  	}
  
  	PUGI__FN xml_node_type xml_node::type() const
  	{
  		return _root ? PUGI__NODETYPE(_root) : node_null;
  	}
  
  	PUGI__FN const char_t* xml_node::value() const
  	{
  		return (_root && _root->value) ? _root->value + 0 : PUGIXML_TEXT("");
  	}
  
  	PUGI__FN xml_node xml_node::child(const char_t* name_) const
  	{
  		if (!_root) return xml_node();
  
  		for (xml_node_struct* i = _root->first_child; i; i = i->next_sibling)
  			if (i->name && impl::strequal(name_, i->name)) return xml_node(i);
  
  		return xml_node();
  	}
  
  	PUGI__FN xml_attribute xml_node::attribute(const char_t* name_) const
  	{
  		if (!_root) return xml_attribute();
  
  		for (xml_attribute_struct* i = _root->first_attribute; i; i = i->next_attribute)
  			if (i->name && impl::strequal(name_, i->name))
  				return xml_attribute(i);
  
  		return xml_attribute();
  	}
  
  	PUGI__FN xml_node xml_node::next_sibling(const char_t* name_) const
  	{
  		if (!_root) return xml_node();
  
  		for (xml_node_struct* i = _root->next_sibling; i; i = i->next_sibling)
  			if (i->name && impl::strequal(name_, i->name)) return xml_node(i);
  
  		return xml_node();
  	}
  
  	PUGI__FN xml_node xml_node::next_sibling() const
  	{
  		return _root ? xml_node(_root->next_sibling) : xml_node();
  	}
  
  	PUGI__FN xml_node xml_node::previous_sibling(const char_t* name_) const
  	{
  		if (!_root) return xml_node();
  
  		for (xml_node_struct* i = _root->prev_sibling_c; i->next_sibling; i = i->prev_sibling_c)
  			if (i->name && impl::strequal(name_, i->name)) return xml_node(i);
  
  		return xml_node();
  	}
  
  	PUGI__FN xml_attribute xml_node::attribute(const char_t* name_, xml_attribute& hint_) const
  	{
  		xml_attribute_struct* hint = hint_._attr;
  
  		// if hint is not an attribute of node, behavior is not defined
  		assert(!hint || (_root && impl::is_attribute_of(hint, _root)));
  
  		if (!_root) return xml_attribute();
  
  		// optimistically search from hint up until the end
  		for (xml_attribute_struct* i = hint; i; i = i->next_attribute)
  			if (i->name && impl::strequal(name_, i->name))
  			{
  				// update hint to maximize efficiency of searching for consecutive attributes
  				hint_._attr = i->next_attribute;
  
  				return xml_attribute(i);
  			}
  
  		// wrap around and search from the first attribute until the hint
  		// 'j' null pointer check is technically redundant, but it prevents a crash in case the assertion above fails
  		for (xml_attribute_struct* j = _root->first_attribute; j && j != hint; j = j->next_attribute)
  			if (j->name && impl::strequal(name_, j->name))
  			{
  				// update hint to maximize efficiency of searching for consecutive attributes
  				hint_._attr = j->next_attribute;
  
  				return xml_attribute(j);
  			}
  
  		return xml_attribute();
  	}
  
  	PUGI__FN xml_node xml_node::previous_sibling() const
  	{
  		if (!_root) return xml_node();
  
  		if (_root->prev_sibling_c->next_sibling) return xml_node(_root->prev_sibling_c);
  		else return xml_node();
  	}
  
  	PUGI__FN xml_node xml_node::parent() const
  	{
  		return _root ? xml_node(_root->parent) : xml_node();
  	}
  
  	PUGI__FN xml_node xml_node::root() const
  	{
  		return _root ? xml_node(&impl::get_document(_root)) : xml_node();
  	}
  
  	PUGI__FN xml_text xml_node::text() const
  	{
  		return xml_text(_root);
  	}
  
  	PUGI__FN const char_t* xml_node::child_value() const
  	{
  		if (!_root) return PUGIXML_TEXT("");
  
  		// element nodes can have value if parse_embed_pcdata was used
  		if (PUGI__NODETYPE(_root) == node_element && _root->value)
  			return _root->value;
  
  		for (xml_node_struct* i = _root->first_child; i; i = i->next_sibling)
  			if (impl::is_text_node(i) && i->value)
  				return i->value;
  
  		return PUGIXML_TEXT("");
  	}
  
  	PUGI__FN const char_t* xml_node::child_value(const char_t* name_) const
  	{
  		return child(name_).child_value();
  	}
  
  	PUGI__FN xml_attribute xml_node::first_attribute() const
  	{
  		return _root ? xml_attribute(_root->first_attribute) : xml_attribute();
  	}
  
  	PUGI__FN xml_attribute xml_node::last_attribute() const
  	{
  		return _root && _root->first_attribute ? xml_attribute(_root->first_attribute->prev_attribute_c) : xml_attribute();
  	}
  
  	PUGI__FN xml_node xml_node::first_child() const
  	{
  		return _root ? xml_node(_root->first_child) : xml_node();
  	}
  
  	PUGI__FN xml_node xml_node::last_child() const
  	{
  		return _root && _root->first_child ? xml_node(_root->first_child->prev_sibling_c) : xml_node();
  	}
  
  	PUGI__FN bool xml_node::set_name(const char_t* rhs)
  	{
  		xml_node_type type_ = _root ? PUGI__NODETYPE(_root) : node_null;
  
  		if (type_ != node_element && type_ != node_pi && type_ != node_declaration)
  			return false;
  
  		return impl::strcpy_insitu(_root->name, _root->header, impl::xml_memory_page_name_allocated_mask, rhs, impl::strlength(rhs));
  	}
  
  	PUGI__FN bool xml_node::set_value(const char_t* rhs)
  	{
  		xml_node_type type_ = _root ? PUGI__NODETYPE(_root) : node_null;
  
  		if (type_ != node_pcdata && type_ != node_cdata && type_ != node_comment && type_ != node_pi && type_ != node_doctype)
  			return false;
  
  		return impl::strcpy_insitu(_root->value, _root->header, impl::xml_memory_page_value_allocated_mask, rhs, impl::strlength(rhs));
  	}
  
  	PUGI__FN xml_attribute xml_node::append_attribute(const char_t* name_)
  	{
  		if (!impl::allow_insert_attribute(type())) return xml_attribute();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_attribute();
  
  		xml_attribute a(impl::allocate_attribute(alloc));
  		if (!a) return xml_attribute();
  
  		impl::append_attribute(a._attr, _root);
  
  		a.set_name(name_);
  
  		return a;
  	}
  
  	PUGI__FN xml_attribute xml_node::prepend_attribute(const char_t* name_)
  	{
  		if (!impl::allow_insert_attribute(type())) return xml_attribute();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_attribute();
  
  		xml_attribute a(impl::allocate_attribute(alloc));
  		if (!a) return xml_attribute();
  
  		impl::prepend_attribute(a._attr, _root);
  
  		a.set_name(name_);
  
  		return a;
  	}
  
  	PUGI__FN xml_attribute xml_node::insert_attribute_after(const char_t* name_, const xml_attribute& attr)
  	{
  		if (!impl::allow_insert_attribute(type())) return xml_attribute();
  		if (!attr || !impl::is_attribute_of(attr._attr, _root)) return xml_attribute();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_attribute();
  
  		xml_attribute a(impl::allocate_attribute(alloc));
  		if (!a) return xml_attribute();
  
  		impl::insert_attribute_after(a._attr, attr._attr, _root);
  
  		a.set_name(name_);
  
  		return a;
  	}
  
  	PUGI__FN xml_attribute xml_node::insert_attribute_before(const char_t* name_, const xml_attribute& attr)
  	{
  		if (!impl::allow_insert_attribute(type())) return xml_attribute();
  		if (!attr || !impl::is_attribute_of(attr._attr, _root)) return xml_attribute();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_attribute();
  
  		xml_attribute a(impl::allocate_attribute(alloc));
  		if (!a) return xml_attribute();
  
  		impl::insert_attribute_before(a._attr, attr._attr, _root);
  
  		a.set_name(name_);
  
  		return a;
  	}
  
  	PUGI__FN xml_attribute xml_node::append_copy(const xml_attribute& proto)
  	{
  		if (!proto) return xml_attribute();
  		if (!impl::allow_insert_attribute(type())) return xml_attribute();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_attribute();
  
  		xml_attribute a(impl::allocate_attribute(alloc));
  		if (!a) return xml_attribute();
  
  		impl::append_attribute(a._attr, _root);
  		impl::node_copy_attribute(a._attr, proto._attr);
  
  		return a;
  	}
  
  	PUGI__FN xml_attribute xml_node::prepend_copy(const xml_attribute& proto)
  	{
  		if (!proto) return xml_attribute();
  		if (!impl::allow_insert_attribute(type())) return xml_attribute();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_attribute();
  
  		xml_attribute a(impl::allocate_attribute(alloc));
  		if (!a) return xml_attribute();
  
  		impl::prepend_attribute(a._attr, _root);
  		impl::node_copy_attribute(a._attr, proto._attr);
  
  		return a;
  	}
  
  	PUGI__FN xml_attribute xml_node::insert_copy_after(const xml_attribute& proto, const xml_attribute& attr)
  	{
  		if (!proto) return xml_attribute();
  		if (!impl::allow_insert_attribute(type())) return xml_attribute();
  		if (!attr || !impl::is_attribute_of(attr._attr, _root)) return xml_attribute();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_attribute();
  
  		xml_attribute a(impl::allocate_attribute(alloc));
  		if (!a) return xml_attribute();
  
  		impl::insert_attribute_after(a._attr, attr._attr, _root);
  		impl::node_copy_attribute(a._attr, proto._attr);
  
  		return a;
  	}
  
  	PUGI__FN xml_attribute xml_node::insert_copy_before(const xml_attribute& proto, const xml_attribute& attr)
  	{
  		if (!proto) return xml_attribute();
  		if (!impl::allow_insert_attribute(type())) return xml_attribute();
  		if (!attr || !impl::is_attribute_of(attr._attr, _root)) return xml_attribute();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_attribute();
  
  		xml_attribute a(impl::allocate_attribute(alloc));
  		if (!a) return xml_attribute();
  
  		impl::insert_attribute_before(a._attr, attr._attr, _root);
  		impl::node_copy_attribute(a._attr, proto._attr);
  
  		return a;
  	}
  
  	PUGI__FN xml_node xml_node::append_child(xml_node_type type_)
  	{
  		if (!impl::allow_insert_child(type(), type_)) return xml_node();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_node();
  
  		xml_node n(impl::allocate_node(alloc, type_));
  		if (!n) return xml_node();
  
  		impl::append_node(n._root, _root);
  
  		if (type_ == node_declaration) n.set_name(PUGIXML_TEXT("xml"));
  
  		return n;
  	}
  
  	PUGI__FN xml_node xml_node::prepend_child(xml_node_type type_)
  	{
  		if (!impl::allow_insert_child(type(), type_)) return xml_node();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_node();
  
  		xml_node n(impl::allocate_node(alloc, type_));
  		if (!n) return xml_node();
  
  		impl::prepend_node(n._root, _root);
  
  		if (type_ == node_declaration) n.set_name(PUGIXML_TEXT("xml"));
  
  		return n;
  	}
  
  	PUGI__FN xml_node xml_node::insert_child_before(xml_node_type type_, const xml_node& node)
  	{
  		if (!impl::allow_insert_child(type(), type_)) return xml_node();
  		if (!node._root || node._root->parent != _root) return xml_node();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_node();
  
  		xml_node n(impl::allocate_node(alloc, type_));
  		if (!n) return xml_node();
  
  		impl::insert_node_before(n._root, node._root);
  
  		if (type_ == node_declaration) n.set_name(PUGIXML_TEXT("xml"));
  
  		return n;
  	}
  
  	PUGI__FN xml_node xml_node::insert_child_after(xml_node_type type_, const xml_node& node)
  	{
  		if (!impl::allow_insert_child(type(), type_)) return xml_node();
  		if (!node._root || node._root->parent != _root) return xml_node();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_node();
  
  		xml_node n(impl::allocate_node(alloc, type_));
  		if (!n) return xml_node();
  
  		impl::insert_node_after(n._root, node._root);
  
  		if (type_ == node_declaration) n.set_name(PUGIXML_TEXT("xml"));
  
  		return n;
  	}
  
  	PUGI__FN xml_node xml_node::append_child(const char_t* name_)
  	{
  		xml_node result = append_child(node_element);
  
  		result.set_name(name_);
  
  		return result;
  	}
  
  	PUGI__FN xml_node xml_node::prepend_child(const char_t* name_)
  	{
  		xml_node result = prepend_child(node_element);
  
  		result.set_name(name_);
  
  		return result;
  	}
  
  	PUGI__FN xml_node xml_node::insert_child_after(const char_t* name_, const xml_node& node)
  	{
  		xml_node result = insert_child_after(node_element, node);
  
  		result.set_name(name_);
  
  		return result;
  	}
  
  	PUGI__FN xml_node xml_node::insert_child_before(const char_t* name_, const xml_node& node)
  	{
  		xml_node result = insert_child_before(node_element, node);
  
  		result.set_name(name_);
  
  		return result;
  	}
  
  	PUGI__FN xml_node xml_node::append_copy(const xml_node& proto)
  	{
  		xml_node_type type_ = proto.type();
  		if (!impl::allow_insert_child(type(), type_)) return xml_node();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_node();
  
  		xml_node n(impl::allocate_node(alloc, type_));
  		if (!n) return xml_node();
  
  		impl::append_node(n._root, _root);
  		impl::node_copy_tree(n._root, proto._root);
  
  		return n;
  	}
  
  	PUGI__FN xml_node xml_node::prepend_copy(const xml_node& proto)
  	{
  		xml_node_type type_ = proto.type();
  		if (!impl::allow_insert_child(type(), type_)) return xml_node();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_node();
  
  		xml_node n(impl::allocate_node(alloc, type_));
  		if (!n) return xml_node();
  
  		impl::prepend_node(n._root, _root);
  		impl::node_copy_tree(n._root, proto._root);
  
  		return n;
  	}
  
  	PUGI__FN xml_node xml_node::insert_copy_after(const xml_node& proto, const xml_node& node)
  	{
  		xml_node_type type_ = proto.type();
  		if (!impl::allow_insert_child(type(), type_)) return xml_node();
  		if (!node._root || node._root->parent != _root) return xml_node();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_node();
  
  		xml_node n(impl::allocate_node(alloc, type_));
  		if (!n) return xml_node();
  
  		impl::insert_node_after(n._root, node._root);
  		impl::node_copy_tree(n._root, proto._root);
  
  		return n;
  	}
  
  	PUGI__FN xml_node xml_node::insert_copy_before(const xml_node& proto, const xml_node& node)
  	{
  		xml_node_type type_ = proto.type();
  		if (!impl::allow_insert_child(type(), type_)) return xml_node();
  		if (!node._root || node._root->parent != _root) return xml_node();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_node();
  
  		xml_node n(impl::allocate_node(alloc, type_));
  		if (!n) return xml_node();
  
  		impl::insert_node_before(n._root, node._root);
  		impl::node_copy_tree(n._root, proto._root);
  
  		return n;
  	}
  
  	PUGI__FN xml_node xml_node::append_move(const xml_node& moved)
  	{
  		if (!impl::allow_move(*this, moved)) return xml_node();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_node();
  
  		// disable document_buffer_order optimization since moving nodes around changes document order without changing buffer pointers
  		impl::get_document(_root).header |= impl::xml_memory_page_contents_shared_mask;
  
  		impl::remove_node(moved._root);
  		impl::append_node(moved._root, _root);
  
  		return moved;
  	}
  
  	PUGI__FN xml_node xml_node::prepend_move(const xml_node& moved)
  	{
  		if (!impl::allow_move(*this, moved)) return xml_node();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_node();
  
  		// disable document_buffer_order optimization since moving nodes around changes document order without changing buffer pointers
  		impl::get_document(_root).header |= impl::xml_memory_page_contents_shared_mask;
  
  		impl::remove_node(moved._root);
  		impl::prepend_node(moved._root, _root);
  
  		return moved;
  	}
  
  	PUGI__FN xml_node xml_node::insert_move_after(const xml_node& moved, const xml_node& node)
  	{
  		if (!impl::allow_move(*this, moved)) return xml_node();
  		if (!node._root || node._root->parent != _root) return xml_node();
  		if (moved._root == node._root) return xml_node();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_node();
  
  		// disable document_buffer_order optimization since moving nodes around changes document order without changing buffer pointers
  		impl::get_document(_root).header |= impl::xml_memory_page_contents_shared_mask;
  
  		impl::remove_node(moved._root);
  		impl::insert_node_after(moved._root, node._root);
  
  		return moved;
  	}
  
  	PUGI__FN xml_node xml_node::insert_move_before(const xml_node& moved, const xml_node& node)
  	{
  		if (!impl::allow_move(*this, moved)) return xml_node();
  		if (!node._root || node._root->parent != _root) return xml_node();
  		if (moved._root == node._root) return xml_node();
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return xml_node();
  
  		// disable document_buffer_order optimization since moving nodes around changes document order without changing buffer pointers
  		impl::get_document(_root).header |= impl::xml_memory_page_contents_shared_mask;
  
  		impl::remove_node(moved._root);
  		impl::insert_node_before(moved._root, node._root);
  
  		return moved;
  	}
  
  	PUGI__FN bool xml_node::remove_attribute(const char_t* name_)
  	{
  		return remove_attribute(attribute(name_));
  	}
  
  	PUGI__FN bool xml_node::remove_attribute(const xml_attribute& a)
  	{
  		if (!_root || !a._attr) return false;
  		if (!impl::is_attribute_of(a._attr, _root)) return false;
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return false;
  
  		impl::remove_attribute(a._attr, _root);
  		impl::destroy_attribute(a._attr, alloc);
  
  		return true;
  	}
  
  	PUGI__FN bool xml_node::remove_child(const char_t* name_)
  	{
  		return remove_child(child(name_));
  	}
  
  	PUGI__FN bool xml_node::remove_child(const xml_node& n)
  	{
  		if (!_root || !n._root || n._root->parent != _root) return false;
  
  		impl::xml_allocator& alloc = impl::get_allocator(_root);
  		if (!alloc.reserve()) return false;
  
  		impl::remove_node(n._root);
  		impl::destroy_node(n._root, alloc);
  
  		return true;
  	}
  
  	PUGI__FN xml_parse_result xml_node::append_buffer(const void* contents, size_t size, unsigned int options, xml_encoding encoding)
  	{
  		// append_buffer is only valid for elements/documents
  		if (!impl::allow_insert_child(type(), node_element)) return impl::make_parse_result(status_append_invalid_root);
  
  		// get document node
  		impl::xml_document_struct* doc = &impl::get_document(_root);
  
  		// disable document_buffer_order optimization since in a document with multiple buffers comparing buffer pointers does not make sense
  		doc->header |= impl::xml_memory_page_contents_shared_mask;
  
  		// get extra buffer element (we'll store the document fragment buffer there so that we can deallocate it later)
  		impl::xml_memory_page* page = 0;
  		impl::xml_extra_buffer* extra = static_cast<impl::xml_extra_buffer*>(doc->allocate_memory(sizeof(impl::xml_extra_buffer), page));
  		(void)page;
  
  		if (!extra) return impl::make_parse_result(status_out_of_memory);
  
  		// add extra buffer to the list
  		extra->buffer = 0;
  		extra->next = doc->extra_buffers;
  		doc->extra_buffers = extra;
  
  		// name of the root has to be NULL before parsing - otherwise closing node mismatches will not be detected at the top level
  		impl::name_null_sentry sentry(_root);
  
  		return impl::load_buffer_impl(doc, _root, const_cast<void*>(contents), size, options, encoding, false, false, &extra->buffer);
  	}
  
  	PUGI__FN xml_node xml_node::find_child_by_attribute(const char_t* name_, const char_t* attr_name, const char_t* attr_value) const
  	{
  		if (!_root) return xml_node();
  
  		for (xml_node_struct* i = _root->first_child; i; i = i->next_sibling)
  			if (i->name && impl::strequal(name_, i->name))
  			{
  				for (xml_attribute_struct* a = i->first_attribute; a; a = a->next_attribute)
  					if (a->name && impl::strequal(attr_name, a->name) && impl::strequal(attr_value, a->value ? a->value + 0 : PUGIXML_TEXT("")))
  						return xml_node(i);
  			}
  
  		return xml_node();
  	}
  
  	PUGI__FN xml_node xml_node::find_child_by_attribute(const char_t* attr_name, const char_t* attr_value) const
  	{
  		if (!_root) return xml_node();
  
  		for (xml_node_struct* i = _root->first_child; i; i = i->next_sibling)
  			for (xml_attribute_struct* a = i->first_attribute; a; a = a->next_attribute)
  				if (a->name && impl::strequal(attr_name, a->name) && impl::strequal(attr_value, a->value ? a->value + 0 : PUGIXML_TEXT("")))
  					return xml_node(i);
  
  		return xml_node();
  	}
  
  #ifndef PUGIXML_NO_STL
  	PUGI__FN string_t xml_node::path(char_t delimiter) const
  	{
  		if (!_root) return string_t();
  
  		size_t offset = 0;
  
  		for (xml_node_struct* i = _root; i; i = i->parent)
  		{
  			offset += (i != _root);
  			offset += i->name ? impl::strlength(i->name) : 0;
  		}
  
  		string_t result;
  		result.resize(offset);
  
  		for (xml_node_struct* j = _root; j; j = j->parent)
  		{
  			if (j != _root)
  				result[--offset] = delimiter;
  
  			if (j->name)
  			{
  				size_t length = impl::strlength(j->name);
  
  				offset -= length;
  				memcpy(&result[offset], j->name, length * sizeof(char_t));
  			}
  		}
  
  		assert(offset == 0);
  
  		return result;
  	}
  #endif
  
  	PUGI__FN xml_node xml_node::first_element_by_path(const char_t* path_, char_t delimiter) const
  	{
  		xml_node found = *this; // Current search context.
  
  		if (!_root || !path_[0]) return found;
  
  		if (path_[0] == delimiter)
  		{
  			// Absolute path; e.g. '/foo/bar'
  			found = found.root();
  			++path_;
  		}
  
  		const char_t* path_segment = path_;
  
  		while (*path_segment == delimiter) ++path_segment;
  
  		const char_t* path_segment_end = path_segment;
  
  		while (*path_segment_end && *path_segment_end != delimiter) ++path_segment_end;
  
  		if (path_segment == path_segment_end) return found;
  
  		const char_t* next_segment = path_segment_end;
  
  		while (*next_segment == delimiter) ++next_segment;
  
  		if (*path_segment == '.' && path_segment + 1 == path_segment_end)
  			return found.first_element_by_path(next_segment, delimiter);
  		else if (*path_segment == '.' && *(path_segment+1) == '.' && path_segment + 2 == path_segment_end)
  			return found.parent().first_element_by_path(next_segment, delimiter);
  		else
  		{
  			for (xml_node_struct* j = found._root->first_child; j; j = j->next_sibling)
  			{
  				if (j->name && impl::strequalrange(j->name, path_segment, static_cast<size_t>(path_segment_end - path_segment)))
  				{
  					xml_node subsearch = xml_node(j).first_element_by_path(next_segment, delimiter);
  
  					if (subsearch) return subsearch;
  				}
  			}
  
  			return xml_node();
  		}
  	}
  
  	PUGI__FN bool xml_node::traverse(xml_tree_walker& walker)
  	{
  		walker._depth = -1;
  
  		xml_node arg_begin(_root);
  		if (!walker.begin(arg_begin)) return false;
  
  		xml_node_struct* cur = _root ? _root->first_child + 0 : 0;
  
  		if (cur)
  		{
  			++walker._depth;
  
  			do
  			{
  				xml_node arg_for_each(cur);
  				if (!walker.for_each(arg_for_each))
  					return false;
  
  				if (cur->first_child)
  				{
  					++walker._depth;
  					cur = cur->first_child;
  				}
  				else if (cur->next_sibling)
  					cur = cur->next_sibling;
  				else
  				{
  					while (!cur->next_sibling && cur != _root && cur->parent)
  					{
  						--walker._depth;
  						cur = cur->parent;
  					}
  
  					if (cur != _root)
  						cur = cur->next_sibling;
  				}
  			}
  			while (cur && cur != _root);
  		}
  
  		assert(walker._depth == -1);
  
  		xml_node arg_end(_root);
  		return walker.end(arg_end);
  	}
  
  	PUGI__FN size_t xml_node::hash_value() const
  	{
  		return static_cast<size_t>(reinterpret_cast<uintptr_t>(_root) / sizeof(xml_node_struct));
  	}
  
  	PUGI__FN xml_node_struct* xml_node::internal_object() const
  	{
  		return _root;
  	}
  
  	PUGI__FN void xml_node::print(xml_writer& writer, const char_t* indent, unsigned int flags, xml_encoding encoding, unsigned int depth) const
  	{
  		if (!_root) return;
  
  		impl::xml_buffered_writer buffered_writer(writer, encoding);
  
  		impl::node_output(buffered_writer, _root, indent, flags, depth);
  
  		buffered_writer.flush();
  	}
  
  #ifndef PUGIXML_NO_STL
  	PUGI__FN void xml_node::print(std::basic_ostream<char, std::char_traits<char> >& stream, const char_t* indent, unsigned int flags, xml_encoding encoding, unsigned int depth) const
  	{
  		xml_writer_stream writer(stream);
  
  		print(writer, indent, flags, encoding, depth);
  	}
  
  	PUGI__FN void xml_node::print(std::basic_ostream<wchar_t, std::char_traits<wchar_t> >& stream, const char_t* indent, unsigned int flags, unsigned int depth) const
  	{
  		xml_writer_stream writer(stream);
  
  		print(writer, indent, flags, encoding_wchar, depth);
  	}
  #endif
  
  	PUGI__FN ptrdiff_t xml_node::offset_debug() const
  	{
  		if (!_root) return -1;
  
  		impl::xml_document_struct& doc = impl::get_document(_root);
  
  		// we can determine the offset reliably only if there is exactly once parse buffer
  		if (!doc.buffer || doc.extra_buffers) return -1;
  
  		switch (type())
  		{
  		case node_document:
  			return 0;
  
  		case node_element:
  		case node_declaration:
  		case node_pi:
  			return _root->name && (_root->header & impl::xml_memory_page_name_allocated_or_shared_mask) == 0 ? _root->name - doc.buffer : -1;
  
  		case node_pcdata:
  		case node_cdata:
  		case node_comment:
  		case node_doctype:
  			return _root->value && (_root->header & impl::xml_memory_page_value_allocated_or_shared_mask) == 0 ? _root->value - doc.buffer : -1;
  
  		default:
  			assert(false && "Invalid node type"); // unreachable
  			return -1;
  		}
  	}
  
  #ifdef __BORLANDC__
  	PUGI__FN bool operator&&(const xml_node& lhs, bool rhs)
  	{
  		return (bool)lhs && rhs;
  	}
  
  	PUGI__FN bool operator||(const xml_node& lhs, bool rhs)
  	{
  		return (bool)lhs || rhs;
  	}
  #endif
  
  	PUGI__FN xml_text::xml_text(xml_node_struct* root): _root(root)
  	{
  	}
  
  	PUGI__FN xml_node_struct* xml_text::_data() const
  	{
  		if (!_root || impl::is_text_node(_root)) return _root;
  
  		// element nodes can have value if parse_embed_pcdata was used
  		if (PUGI__NODETYPE(_root) == node_element && _root->value)
  			return _root;
  
  		for (xml_node_struct* node = _root->first_child; node; node = node->next_sibling)
  			if (impl::is_text_node(node))
  				return node;
  
  		return 0;
  	}
  
  	PUGI__FN xml_node_struct* xml_text::_data_new()
  	{
  		xml_node_struct* d = _data();
  		if (d) return d;
  
  		return xml_node(_root).append_child(node_pcdata).internal_object();
  	}
  
  	PUGI__FN xml_text::xml_text(): _root(0)
  	{
  	}
  
  	PUGI__FN static void unspecified_bool_xml_text(xml_text***)
  	{
  	}
  
  	PUGI__FN xml_text::operator xml_text::unspecified_bool_type() const
  	{
  		return _data() ? unspecified_bool_xml_text : 0;
  	}
  
  	PUGI__FN bool xml_text::operator!() const
  	{
  		return !_data();
  	}
  
  	PUGI__FN bool xml_text::empty() const
  	{
  		return _data() == 0;
  	}
  
  	PUGI__FN const char_t* xml_text::get() const
  	{
  		xml_node_struct* d = _data();
  
  		return (d && d->value) ? d->value + 0 : PUGIXML_TEXT("");
  	}
  
  	PUGI__FN const char_t* xml_text::as_string(const char_t* def) const
  	{
  		xml_node_struct* d = _data();
  
  		return (d && d->value) ? d->value + 0 : def;
  	}
  
  	PUGI__FN int xml_text::as_int(int def) const
  	{
  		xml_node_struct* d = _data();
  
  		return (d && d->value) ? impl::get_value_int(d->value) : def;
  	}
  
  	PUGI__FN unsigned int xml_text::as_uint(unsigned int def) const
  	{
  		xml_node_struct* d = _data();
  
  		return (d && d->value) ? impl::get_value_uint(d->value) : def;
  	}
  
  	PUGI__FN double xml_text::as_double(double def) const
  	{
  		xml_node_struct* d = _data();
  
  		return (d && d->value) ? impl::get_value_double(d->value) : def;
  	}
  
  	PUGI__FN float xml_text::as_float(float def) const
  	{
  		xml_node_struct* d = _data();
  
  		return (d && d->value) ? impl::get_value_float(d->value) : def;
  	}
  
  	PUGI__FN bool xml_text::as_bool(bool def) const
  	{
  		xml_node_struct* d = _data();
  
  		return (d && d->value) ? impl::get_value_bool(d->value) : def;
  	}
  
  #ifdef PUGIXML_HAS_LONG_LONG
  	PUGI__FN long long xml_text::as_llong(long long def) const
  	{
  		xml_node_struct* d = _data();
  
  		return (d && d->value) ? impl::get_value_llong(d->value) : def;
  	}
  
  	PUGI__FN unsigned long long xml_text::as_ullong(unsigned long long def) const
  	{
  		xml_node_struct* d = _data();
  
  		return (d && d->value) ? impl::get_value_ullong(d->value) : def;
  	}
  #endif
  
  	PUGI__FN bool xml_text::set(const char_t* rhs)
  	{
  		xml_node_struct* dn = _data_new();
  
  		return dn ? impl::strcpy_insitu(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, impl::strlength(rhs)) : false;
  	}
  
  	PUGI__FN bool xml_text::set(int rhs)
  	{
  		xml_node_struct* dn = _data_new();
  
  		return dn ? impl::set_value_integer<unsigned int>(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, rhs < 0) : false;
  	}
  
  	PUGI__FN bool xml_text::set(unsigned int rhs)
  	{
  		xml_node_struct* dn = _data_new();
  
  		return dn ? impl::set_value_integer<unsigned int>(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, false) : false;
  	}
  
  	PUGI__FN bool xml_text::set(long rhs)
  	{
  		xml_node_struct* dn = _data_new();
  
  		return dn ? impl::set_value_integer<unsigned long>(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, rhs < 0) : false;
  	}
  
  	PUGI__FN bool xml_text::set(unsigned long rhs)
  	{
  		xml_node_struct* dn = _data_new();
  
  		return dn ? impl::set_value_integer<unsigned long>(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, false) : false;
  	}
  
  	PUGI__FN bool xml_text::set(float rhs)
  	{
  		xml_node_struct* dn = _data_new();
  
  		return dn ? impl::set_value_convert(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs) : false;
  	}
  
  	PUGI__FN bool xml_text::set(double rhs)
  	{
  		xml_node_struct* dn = _data_new();
  
  		return dn ? impl::set_value_convert(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs) : false;
  	}
  
  	PUGI__FN bool xml_text::set(bool rhs)
  	{
  		xml_node_struct* dn = _data_new();
  
  		return dn ? impl::set_value_bool(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs) : false;
  	}
  
  #ifdef PUGIXML_HAS_LONG_LONG
  	PUGI__FN bool xml_text::set(long long rhs)
  	{
  		xml_node_struct* dn = _data_new();
  
  		return dn ? impl::set_value_integer<unsigned long long>(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, rhs < 0) : false;
  	}
  
  	PUGI__FN bool xml_text::set(unsigned long long rhs)
  	{
  		xml_node_struct* dn = _data_new();
  
  		return dn ? impl::set_value_integer<unsigned long long>(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, false) : false;
  	}
  #endif
  
  	PUGI__FN xml_text& xml_text::operator=(const char_t* rhs)
  	{
  		set(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_text& xml_text::operator=(int rhs)
  	{
  		set(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_text& xml_text::operator=(unsigned int rhs)
  	{
  		set(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_text& xml_text::operator=(long rhs)
  	{
  		set(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_text& xml_text::operator=(unsigned long rhs)
  	{
  		set(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_text& xml_text::operator=(double rhs)
  	{
  		set(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_text& xml_text::operator=(float rhs)
  	{
  		set(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_text& xml_text::operator=(bool rhs)
  	{
  		set(rhs);
  		return *this;
  	}
  
  #ifdef PUGIXML_HAS_LONG_LONG
  	PUGI__FN xml_text& xml_text::operator=(long long rhs)
  	{
  		set(rhs);
  		return *this;
  	}
  
  	PUGI__FN xml_text& xml_text::operator=(unsigned long long rhs)
  	{
  		set(rhs);
  		return *this;
  	}
  #endif
  
  	PUGI__FN xml_node xml_text::data() const
  	{
  		return xml_node(_data());
  	}
  
  #ifdef __BORLANDC__
  	PUGI__FN bool operator&&(const xml_text& lhs, bool rhs)
  	{
  		return (bool)lhs && rhs;
  	}
  
  	PUGI__FN bool operator||(const xml_text& lhs, bool rhs)
  	{
  		return (bool)lhs || rhs;
  	}
  #endif
  
  	PUGI__FN xml_node_iterator::xml_node_iterator()
  	{
  	}
  
  	PUGI__FN xml_node_iterator::xml_node_iterator(const xml_node& node): _wrap(node), _parent(node.parent())
  	{
  	}
  
  	PUGI__FN xml_node_iterator::xml_node_iterator(xml_node_struct* ref, xml_node_struct* parent): _wrap(ref), _parent(parent)
  	{
  	}
  
  	PUGI__FN bool xml_node_iterator::operator==(const xml_node_iterator& rhs) const
  	{
  		return _wrap._root == rhs._wrap._root && _parent._root == rhs._parent._root;
  	}
  
  	PUGI__FN bool xml_node_iterator::operator!=(const xml_node_iterator& rhs) const
  	{
  		return _wrap._root != rhs._wrap._root || _parent._root != rhs._parent._root;
  	}
  
  	PUGI__FN xml_node& xml_node_iterator::operator*() const
  	{
  		assert(_wrap._root);
  		return _wrap;
  	}
  
  	PUGI__FN xml_node* xml_node_iterator::operator->() const
  	{
  		assert(_wrap._root);
  		return const_cast<xml_node*>(&_wrap); // BCC5 workaround
  	}
  
  	PUGI__FN const xml_node_iterator& xml_node_iterator::operator++()
  	{
  		assert(_wrap._root);
  		_wrap._root = _wrap._root->next_sibling;
  		return *this;
  	}
  
  	PUGI__FN xml_node_iterator xml_node_iterator::operator++(int)
  	{
  		xml_node_iterator temp = *this;
  		++*this;
  		return temp;
  	}
  
  	PUGI__FN const xml_node_iterator& xml_node_iterator::operator--()
  	{
  		_wrap = _wrap._root ? _wrap.previous_sibling() : _parent.last_child();
  		return *this;
  	}
  
  	PUGI__FN xml_node_iterator xml_node_iterator::operator--(int)
  	{
  		xml_node_iterator temp = *this;
  		--*this;
  		return temp;
  	}
  
  	PUGI__FN xml_attribute_iterator::xml_attribute_iterator()
  	{
  	}
  
  	PUGI__FN xml_attribute_iterator::xml_attribute_iterator(const xml_attribute& attr, const xml_node& parent): _wrap(attr), _parent(parent)
  	{
  	}
  
  	PUGI__FN xml_attribute_iterator::xml_attribute_iterator(xml_attribute_struct* ref, xml_node_struct* parent): _wrap(ref), _parent(parent)
  	{
  	}
  
  	PUGI__FN bool xml_attribute_iterator::operator==(const xml_attribute_iterator& rhs) const
  	{
  		return _wrap._attr == rhs._wrap._attr && _parent._root == rhs._parent._root;
  	}
  
  	PUGI__FN bool xml_attribute_iterator::operator!=(const xml_attribute_iterator& rhs) const
  	{
  		return _wrap._attr != rhs._wrap._attr || _parent._root != rhs._parent._root;
  	}
  
  	PUGI__FN xml_attribute& xml_attribute_iterator::operator*() const
  	{
  		assert(_wrap._attr);
  		return _wrap;
  	}
  
  	PUGI__FN xml_attribute* xml_attribute_iterator::operator->() const
  	{
  		assert(_wrap._attr);
  		return const_cast<xml_attribute*>(&_wrap); // BCC5 workaround
  	}
  
  	PUGI__FN const xml_attribute_iterator& xml_attribute_iterator::operator++()
  	{
  		assert(_wrap._attr);
  		_wrap._attr = _wrap._attr->next_attribute;
  		return *this;
  	}
  
  	PUGI__FN xml_attribute_iterator xml_attribute_iterator::operator++(int)
  	{
  		xml_attribute_iterator temp = *this;
  		++*this;
  		return temp;
  	}
  
  	PUGI__FN const xml_attribute_iterator& xml_attribute_iterator::operator--()
  	{
  		_wrap = _wrap._attr ? _wrap.previous_attribute() : _parent.last_attribute();
  		return *this;
  	}
  
  	PUGI__FN xml_attribute_iterator xml_attribute_iterator::operator--(int)
  	{
  		xml_attribute_iterator temp = *this;
  		--*this;
  		return temp;
  	}
  
  	PUGI__FN xml_named_node_iterator::xml_named_node_iterator(): _name(0)
  	{
  	}
  
  	PUGI__FN xml_named_node_iterator::xml_named_node_iterator(const xml_node& node, const char_t* name): _wrap(node), _parent(node.parent()), _name(name)
  	{
  	}
  
  	PUGI__FN xml_named_node_iterator::xml_named_node_iterator(xml_node_struct* ref, xml_node_struct* parent, const char_t* name): _wrap(ref), _parent(parent), _name(name)
  	{
  	}
  
  	PUGI__FN bool xml_named_node_iterator::operator==(const xml_named_node_iterator& rhs) const
  	{
  		return _wrap._root == rhs._wrap._root && _parent._root == rhs._parent._root;
  	}
  
  	PUGI__FN bool xml_named_node_iterator::operator!=(const xml_named_node_iterator& rhs) const
  	{
  		return _wrap._root != rhs._wrap._root || _parent._root != rhs._parent._root;
  	}
  
  	PUGI__FN xml_node& xml_named_node_iterator::operator*() const
  	{
  		assert(_wrap._root);
  		return _wrap;
  	}
  
  	PUGI__FN xml_node* xml_named_node_iterator::operator->() const
  	{
  		assert(_wrap._root);
  		return const_cast<xml_node*>(&_wrap); // BCC5 workaround
  	}
  
  	PUGI__FN const xml_named_node_iterator& xml_named_node_iterator::operator++()
  	{
  		assert(_wrap._root);
  		_wrap = _wrap.next_sibling(_name);
  		return *this;
  	}
  
  	PUGI__FN xml_named_node_iterator xml_named_node_iterator::operator++(int)
  	{
  		xml_named_node_iterator temp = *this;
  		++*this;
  		return temp;
  	}
  
  	PUGI__FN const xml_named_node_iterator& xml_named_node_iterator::operator--()
  	{
  		if (_wrap._root)
  			_wrap = _wrap.previous_sibling(_name);
  		else
  		{
  			_wrap = _parent.last_child();
  
  			if (!impl::strequal(_wrap.name(), _name))
  				_wrap = _wrap.previous_sibling(_name);
  		}
  
  		return *this;
  	}
  
  	PUGI__FN xml_named_node_iterator xml_named_node_iterator::operator--(int)
  	{
  		xml_named_node_iterator temp = *this;
  		--*this;
  		return temp;
  	}
  
  	PUGI__FN xml_parse_result::xml_parse_result(): status(status_internal_error), offset(0), encoding(encoding_auto)
  	{
  	}
  
  	PUGI__FN xml_parse_result::operator bool() const
  	{
  		return status == status_ok;
  	}
  
  	PUGI__FN const char* xml_parse_result::description() const
  	{
  		switch (status)
  		{
  		case status_ok: return "No error";
  
  		case status_file_not_found: return "File was not found";
  		case status_io_error: return "Error reading from file/stream";
  		case status_out_of_memory: return "Could not allocate memory";
  		case status_internal_error: return "Internal error occurred";
  
  		case status_unrecognized_tag: return "Could not determine tag type";
  
  		case status_bad_pi: return "Error parsing document declaration/processing instruction";
  		case status_bad_comment: return "Error parsing comment";
  		case status_bad_cdata: return "Error parsing CDATA section";
  		case status_bad_doctype: return "Error parsing document type declaration";
  		case status_bad_pcdata: return "Error parsing PCDATA section";
  		case status_bad_start_element: return "Error parsing start element tag";
  		case status_bad_attribute: return "Error parsing element attribute";
  		case status_bad_end_element: return "Error parsing end element tag";
  		case status_end_element_mismatch: return "Start-end tags mismatch";
  
  		case status_append_invalid_root: return "Unable to append nodes: root is not an element or document";
  
  		case status_no_document_element: return "No document element found";
  
  		default: return "Unknown error";
  		}
  	}
  
  	PUGI__FN xml_document::xml_document(): _buffer(0)
  	{
  		_create();
  	}
  
  	PUGI__FN xml_document::~xml_document()
  	{
  		_destroy();
  	}
  
  #ifdef PUGIXML_HAS_MOVE
  	PUGI__FN xml_document::xml_document(xml_document&& rhs): _buffer(0)
  	{
  		_create();
  		_move(rhs);
  	}
  
  	PUGI__FN xml_document& xml_document::operator=(xml_document&& rhs)
  	{
  		if (this == &rhs) return *this;
  
  		_destroy();
  		_create();
  		_move(rhs);
  
  		return *this;
  	}
  #endif
  
  	PUGI__FN void xml_document::reset()
  	{
  		_destroy();
  		_create();
  	}
  
  	PUGI__FN void xml_document::reset(const xml_document& proto)
  	{
  		reset();
  
  		for (xml_node cur = proto.first_child(); cur; cur = cur.next_sibling())
  			append_copy(cur);
  	}
  
  	PUGI__FN void xml_document::_create()
  	{
  		assert(!_root);
  
  	#ifdef PUGIXML_COMPACT
  		const size_t page_offset = sizeof(uint32_t);
  	#else
  		const size_t page_offset = 0;
  	#endif
  
  		// initialize sentinel page
  		PUGI__STATIC_ASSERT(sizeof(impl::xml_memory_page) + sizeof(impl::xml_document_struct) + page_offset <= sizeof(_memory));
  
  		// prepare page structure
  		impl::xml_memory_page* page = impl::xml_memory_page::construct(_memory);
  		assert(page);
  
  		page->busy_size = impl::xml_memory_page_size;
  
  		// setup first page marker
  	#ifdef PUGIXML_COMPACT
  		// round-trip through void* to avoid 'cast increases required alignment of target type' warning
  		page->compact_page_marker = reinterpret_cast<uint32_t*>(static_cast<void*>(reinterpret_cast<char*>(page) + sizeof(impl::xml_memory_page)));
  		*page->compact_page_marker = sizeof(impl::xml_memory_page);
  	#endif
  
  		// allocate new root
  		_root = new (reinterpret_cast<char*>(page) + sizeof(impl::xml_memory_page) + page_offset) impl::xml_document_struct(page);
  		_root->prev_sibling_c = _root;
  
  		// setup sentinel page
  		page->allocator = static_cast<impl::xml_document_struct*>(_root);
  
  		// setup hash table pointer in allocator
  	#ifdef PUGIXML_COMPACT
  		page->allocator->_hash = &static_cast<impl::xml_document_struct*>(_root)->hash;
  	#endif
  
  		// verify the document allocation
  		assert(reinterpret_cast<char*>(_root) + sizeof(impl::xml_document_struct) <= _memory + sizeof(_memory));
  	}
  
  	PUGI__FN void xml_document::_destroy()
  	{
  		assert(_root);
  
  		// destroy static storage
  		if (_buffer)
  		{
  			impl::xml_memory::deallocate(_buffer);
  			_buffer = 0;
  		}
  
  		// destroy extra buffers (note: no need to destroy linked list nodes, they're allocated using document allocator)
  		for (impl::xml_extra_buffer* extra = static_cast<impl::xml_document_struct*>(_root)->extra_buffers; extra; extra = extra->next)
  		{
  			if (extra->buffer) impl::xml_memory::deallocate(extra->buffer);
  		}
  
  		// destroy dynamic storage, leave sentinel page (it's in static memory)
  		impl::xml_memory_page* root_page = PUGI__GETPAGE(_root);
  		assert(root_page && !root_page->prev);
  		assert(reinterpret_cast<char*>(root_page) >= _memory && reinterpret_cast<char*>(root_page) < _memory + sizeof(_memory));
  
  		for (impl::xml_memory_page* page = root_page->next; page; )
  		{
  			impl::xml_memory_page* next = page->next;
  
  			impl::xml_allocator::deallocate_page(page);
  
  			page = next;
  		}
  
  	#ifdef PUGIXML_COMPACT
  		// destroy hash table
  		static_cast<impl::xml_document_struct*>(_root)->hash.clear();
  	#endif
  
  		_root = 0;
  	}
  
  #ifdef PUGIXML_HAS_MOVE
  	PUGI__FN void xml_document::_move(xml_document& rhs)
  	{
  		impl::xml_document_struct* doc = static_cast<impl::xml_document_struct*>(_root);
  		impl::xml_document_struct* other = static_cast<impl::xml_document_struct*>(rhs._root);
  
  		// save first child pointer for later; this needs hash access
  		xml_node_struct* other_first_child = other->first_child;
  
  	#ifdef PUGIXML_COMPACT
  		// reserve space for the hash table up front; this is the only operation that can fail
  		// if it does, we have no choice but to throw (if we have exceptions)
  		if (other_first_child)
  		{
  			size_t other_children = 0;
  			for (xml_node_struct* node = other_first_child; node; node = node->next_sibling)
  				other_children++;
  
  			// in compact mode, each pointer assignment could result in a hash table request
  			// during move, we have to relocate document first_child and parents of all children
  			// normally there's just one child and its parent has a pointerless encoding but
  			// we assume the worst here
  			if (!other->_hash->reserve(other_children + 1))
  			{
  			#ifdef PUGIXML_NO_EXCEPTIONS
  				return;
  			#else
  				throw std::bad_alloc();
  			#endif
  			}
  		}
  	#endif
  
  		// move allocation state
  		doc->_root = other->_root;
  		doc->_busy_size = other->_busy_size;
  
  		// move buffer state
  		doc->buffer = other->buffer;
  		doc->extra_buffers = other->extra_buffers;
  		_buffer = rhs._buffer;
  
  	#ifdef PUGIXML_COMPACT
  		// move compact hash; note that the hash table can have pointers to other but they will be "inactive", similarly to nodes removed with remove_child
  		doc->hash = other->hash;
  		doc->_hash = &doc->hash;
  
  		// make sure we don't access other hash up until the end when we reinitialize other document
  		other->_hash = 0;
  	#endif
  
  		// move page structure
  		impl::xml_memory_page* doc_page = PUGI__GETPAGE(doc);
  		assert(doc_page && !doc_page->prev && !doc_page->next);
  
  		impl::xml_memory_page* other_page = PUGI__GETPAGE(other);
  		assert(other_page && !other_page->prev);
  
  		// relink pages since root page is embedded into xml_document
  		if (impl::xml_memory_page* page = other_page->next)
  		{
  			assert(page->prev == other_page);
  
  			page->prev = doc_page;
  
  			doc_page->next = page;
  			other_page->next = 0;
  		}
  
  		// make sure pages point to the correct document state
  		for (impl::xml_memory_page* page = doc_page->next; page; page = page->next)
  		{
  			assert(page->allocator == other);
  
  			page->allocator = doc;
  
  		#ifdef PUGIXML_COMPACT
  			// this automatically migrates most children between documents and prevents ->parent assignment from allocating
  			if (page->compact_shared_parent == other)
  				page->compact_shared_parent = doc;
  		#endif
  		}
  
  		// move tree structure
  		assert(!doc->first_child);
  
  		doc->first_child = other_first_child;
  
  		for (xml_node_struct* node = other_first_child; node; node = node->next_sibling)
  		{
  		#ifdef PUGIXML_COMPACT
  			// most children will have migrated when we reassigned compact_shared_parent
  			assert(node->parent == other || node->parent == doc);
  
  			node->parent = doc;
  		#else
  			assert(node->parent == other);
  			node->parent = doc;
  		#endif
  		}
  
  		// reset other document
  		new (other) impl::xml_document_struct(PUGI__GETPAGE(other));
  		rhs._buffer = 0;
  	}
  #endif
  
  #ifndef PUGIXML_NO_STL
  	PUGI__FN xml_parse_result xml_document::load(std::basic_istream<char, std::char_traits<char> >& stream, unsigned int options, xml_encoding encoding)
  	{
  		reset();
  
  		return impl::load_stream_impl(static_cast<impl::xml_document_struct*>(_root), stream, options, encoding, &_buffer);
  	}
  
  	PUGI__FN xml_parse_result xml_document::load(std::basic_istream<wchar_t, std::char_traits<wchar_t> >& stream, unsigned int options)
  	{
  		reset();
  
  		return impl::load_stream_impl(static_cast<impl::xml_document_struct*>(_root), stream, options, encoding_wchar, &_buffer);
  	}
  #endif
  
  	PUGI__FN xml_parse_result xml_document::load_string(const char_t* contents, unsigned int options)
  	{
  		// Force native encoding (skip autodetection)
  	#ifdef PUGIXML_WCHAR_MODE
  		xml_encoding encoding = encoding_wchar;
  	#else
  		xml_encoding encoding = encoding_utf8;
  	#endif
  
  		return load_buffer(contents, impl::strlength(contents) * sizeof(char_t), options, encoding);
  	}
  
  	PUGI__FN xml_parse_result xml_document::load(const char_t* contents, unsigned int options)
  	{
  		return load_string(contents, options);
  	}
  
  	PUGI__FN xml_parse_result xml_document::load_file(const char* path_, unsigned int options, xml_encoding encoding)
  	{
  		reset();
  
  		using impl::auto_deleter; // MSVC7 workaround
  		auto_deleter<FILE> file(fopen(path_, "rb"), impl::close_file);
  
  		return impl::load_file_impl(static_cast<impl::xml_document_struct*>(_root), file.data, options, encoding, &_buffer);
  	}
  
  	PUGI__FN xml_parse_result xml_document::load_file(const wchar_t* path_, unsigned int options, xml_encoding encoding)
  	{
  		reset();
  
  		using impl::auto_deleter; // MSVC7 workaround
  		auto_deleter<FILE> file(impl::open_file_wide(path_, L"rb"), impl::close_file);
  
  		return impl::load_file_impl(static_cast<impl::xml_document_struct*>(_root), file.data, options, encoding, &_buffer);
  	}
  
  	PUGI__FN xml_parse_result xml_document::load_buffer(const void* contents, size_t size, unsigned int options, xml_encoding encoding)
  	{
  		reset();
  
  		return impl::load_buffer_impl(static_cast<impl::xml_document_struct*>(_root), _root, const_cast<void*>(contents), size, options, encoding, false, false, &_buffer);
  	}
  
  	PUGI__FN xml_parse_result xml_document::load_buffer_inplace(void* contents, size_t size, unsigned int options, xml_encoding encoding)
  	{
  		reset();
  
  		return impl::load_buffer_impl(static_cast<impl::xml_document_struct*>(_root), _root, contents, size, options, encoding, true, false, &_buffer);
  	}
  
  	PUGI__FN xml_parse_result xml_document::load_buffer_inplace_own(void* contents, size_t size, unsigned int options, xml_encoding encoding)
  	{
  		reset();
  
  		return impl::load_buffer_impl(static_cast<impl::xml_document_struct*>(_root), _root, contents, size, options, encoding, true, true, &_buffer);
  	}
  
  	PUGI__FN void xml_document::save(xml_writer& writer, const char_t* indent, unsigned int flags, xml_encoding encoding) const
  	{
  		impl::xml_buffered_writer buffered_writer(writer, encoding);
  
  		if ((flags & format_write_bom) && encoding != encoding_latin1)
  		{
  			// BOM always represents the codepoint U+FEFF, so just write it in native encoding
  		#ifdef PUGIXML_WCHAR_MODE
  			unsigned int bom = 0xfeff;
  			buffered_writer.write(static_cast<wchar_t>(bom));
  		#else
  			buffered_writer.write('\xef', '\xbb', '\xbf');
  		#endif
  		}
  
  		if (!(flags & format_no_declaration) && !impl::has_declaration(_root))
  		{
  			buffered_writer.write_string(PUGIXML_TEXT("<?xml version=\"1.0\""));
  			if (encoding == encoding_latin1) buffered_writer.write_string(PUGIXML_TEXT(" encoding=\"ISO-8859-1\""));
  			buffered_writer.write('?', '>');
  			if (!(flags & format_raw)) buffered_writer.write('\n');
  		}
  
  		impl::node_output(buffered_writer, _root, indent, flags, 0);
  
  		buffered_writer.flush();
  	}
  
  #ifndef PUGIXML_NO_STL
  	PUGI__FN void xml_document::save(std::basic_ostream<char, std::char_traits<char> >& stream, const char_t* indent, unsigned int flags, xml_encoding encoding) const
  	{
  		xml_writer_stream writer(stream);
  
  		save(writer, indent, flags, encoding);
  	}
  
  	PUGI__FN void xml_document::save(std::basic_ostream<wchar_t, std::char_traits<wchar_t> >& stream, const char_t* indent, unsigned int flags) const
  	{
  		xml_writer_stream writer(stream);
  
  		save(writer, indent, flags, encoding_wchar);
  	}
  #endif
  
  	PUGI__FN bool xml_document::save_file(const char* path_, const char_t* indent, unsigned int flags, xml_encoding encoding) const
  	{
  		using impl::auto_deleter; // MSVC7 workaround
  		auto_deleter<FILE> file(fopen(path_, (flags & format_save_file_text) ? "w" : "wb"), impl::close_file);
  
  		return impl::save_file_impl(*this, file.data, indent, flags, encoding);
  	}
  
  	PUGI__FN bool xml_document::save_file(const wchar_t* path_, const char_t* indent, unsigned int flags, xml_encoding encoding) const
  	{
  		using impl::auto_deleter; // MSVC7 workaround
  		auto_deleter<FILE> file(impl::open_file_wide(path_, (flags & format_save_file_text) ? L"w" : L"wb"), impl::close_file);
  
  		return impl::save_file_impl(*this, file.data, indent, flags, encoding);
  	}
  
  	PUGI__FN xml_node xml_document::document_element() const
  	{
  		assert(_root);
  
  		for (xml_node_struct* i = _root->first_child; i; i = i->next_sibling)
  			if (PUGI__NODETYPE(i) == node_element)
  				return xml_node(i);
  
  		return xml_node();
  	}
  
  #ifndef PUGIXML_NO_STL
  	PUGI__FN std::string PUGIXML_FUNCTION as_utf8(const wchar_t* str)
  	{
  		assert(str);
  
  		return impl::as_utf8_impl(str, impl::strlength_wide(str));
  	}
  
  	PUGI__FN std::string PUGIXML_FUNCTION as_utf8(const std::basic_string<wchar_t>& str)
  	{
  		return impl::as_utf8_impl(str.c_str(), str.size());
  	}
  
  	PUGI__FN std::basic_string<wchar_t> PUGIXML_FUNCTION as_wide(const char* str)
  	{
  		assert(str);
  
  		return impl::as_wide_impl(str, strlen(str));
  	}
  
  	PUGI__FN std::basic_string<wchar_t> PUGIXML_FUNCTION as_wide(const std::string& str)
  	{
  		return impl::as_wide_impl(str.c_str(), str.size());
  	}
  #endif
  
  	PUGI__FN void PUGIXML_FUNCTION set_memory_management_functions(allocation_function allocate, deallocation_function deallocate)
  	{
  		impl::xml_memory::allocate = allocate;
  		impl::xml_memory::deallocate = deallocate;
  	}
  
  	PUGI__FN allocation_function PUGIXML_FUNCTION get_memory_allocation_function()
  	{
  		return impl::xml_memory::allocate;
  	}
  
  	PUGI__FN deallocation_function PUGIXML_FUNCTION get_memory_deallocation_function()
  	{
  		return impl::xml_memory::deallocate;
  	}
  }
  
  #if !defined(PUGIXML_NO_STL) && (defined(_MSC_VER) || defined(__ICC))
  namespace std
  {
  	// Workarounds for (non-standard) iterator category detection for older versions (MSVC7/IC8 and earlier)
  	PUGI__FN std::bidirectional_iterator_tag _Iter_cat(const pugi::xml_node_iterator&)
  	{
  		return std::bidirectional_iterator_tag();
  	}
  
  	PUGI__FN std::bidirectional_iterator_tag _Iter_cat(const pugi::xml_attribute_iterator&)
  	{
  		return std::bidirectional_iterator_tag();
  	}
  
  	PUGI__FN std::bidirectional_iterator_tag _Iter_cat(const pugi::xml_named_node_iterator&)
  	{
  		return std::bidirectional_iterator_tag();
  	}
  }
  #endif
  
  #if !defined(PUGIXML_NO_STL) && defined(__SUNPRO_CC)
  namespace std
  {
  	// Workarounds for (non-standard) iterator category detection
  	PUGI__FN std::bidirectional_iterator_tag __iterator_category(const pugi::xml_node_iterator&)
  	{
  		return std::bidirectional_iterator_tag();
  	}
  
  	PUGI__FN std::bidirectional_iterator_tag __iterator_category(const pugi::xml_attribute_iterator&)
  	{
  		return std::bidirectional_iterator_tag();
  	}
  
  	PUGI__FN std::bidirectional_iterator_tag __iterator_category(const pugi::xml_named_node_iterator&)
  	{
  		return std::bidirectional_iterator_tag();
  	}
  }
  #endif
  
  #ifndef PUGIXML_NO_XPATH
  // STL replacements
  PUGI__NS_BEGIN
  	struct equal_to
  	{
  		template <typename T> bool operator()(const T& lhs, const T& rhs) const
  		{
  			return lhs == rhs;
  		}
  	};
  
  	struct not_equal_to
  	{
  		template <typename T> bool operator()(const T& lhs, const T& rhs) const
  		{
  			return lhs != rhs;
  		}
  	};
  
  	struct less
  	{
  		template <typename T> bool operator()(const T& lhs, const T& rhs) const
  		{
  			return lhs < rhs;
  		}
  	};
  
  	struct less_equal
  	{
  		template <typename T> bool operator()(const T& lhs, const T& rhs) const
  		{
  			return lhs <= rhs;
  		}
  	};
  
  	template <typename T> void swap(T& lhs, T& rhs)
  	{
  		T temp = lhs;
  		lhs = rhs;
  		rhs = temp;
  	}
  
  	template <typename I, typename Pred> I min_element(I begin, I end, const Pred& pred)
  	{
  		I result = begin;
  
  		for (I it = begin + 1; it != end; ++it)
  			if (pred(*it, *result))
  				result = it;
  
  		return result;
  	}
  
  	template <typename I> void reverse(I begin, I end)
  	{
  		while (end - begin > 1) swap(*begin++, *--end);
  	}
  
  	template <typename I> I unique(I begin, I end)
  	{
  		// fast skip head
  		while (end - begin > 1 && *begin != *(begin + 1)) begin++;
  
  		if (begin == end) return begin;
  
  		// last written element
  		I write = begin++;
  
  		// merge unique elements
  		while (begin != end)
  		{
  			if (*begin != *write)
  				*++write = *begin++;
  			else
  				begin++;
  		}
  
  		// past-the-end (write points to live element)
  		return write + 1;
  	}
  
  	template <typename T, typename Pred> void insertion_sort(T* begin, T* end, const Pred& pred)
  	{
  		if (begin == end)
  			return;
  
  		for (T* it = begin + 1; it != end; ++it)
  		{
  			T val = *it;
  			T* hole = it;
  
  			// move hole backwards
  			while (hole > begin && pred(val, *(hole - 1)))
  			{
  				*hole = *(hole - 1);
  				hole--;
  			}
  
  			// fill hole with element
  			*hole = val;
  		}
  	}
  
  	template <typename I, typename Pred> I median3(I first, I middle, I last, const Pred& pred)
  	{
  		if (pred(*middle, *first)) swap(middle, first);
  		if (pred(*last, *middle)) swap(last, middle);
  		if (pred(*middle, *first)) swap(middle, first);
  
  		return middle;
  	}
  
  	template <typename T, typename Pred> void partition3(T* begin, T* end, T pivot, const Pred& pred, T** out_eqbeg, T** out_eqend)
  	{
  		// invariant: array is split into 4 groups: = < ? > (each variable denotes the boundary between the groups)
  		T* eq = begin;
  		T* lt = begin;
  		T* gt = end;
  
  		while (lt < gt)
  		{
  			if (pred(*lt, pivot))
  				lt++;
  			else if (*lt == pivot)
  				swap(*eq++, *lt++);
  			else
  				swap(*lt, *--gt);
  		}
  
  		// we now have just 4 groups: = < >; move equal elements to the middle
  		T* eqbeg = gt;
  
  		for (T* it = begin; it != eq; ++it)
  			swap(*it, *--eqbeg);
  
  		*out_eqbeg = eqbeg;
  		*out_eqend = gt;
  	}
  
  	template <typename I, typename Pred> void sort(I begin, I end, const Pred& pred)
  	{
  		// sort large chunks
  		while (end - begin > 16)
  		{
  			// find median element
  			I middle = begin + (end - begin) / 2;
  			I median = median3(begin, middle, end - 1, pred);
  
  			// partition in three chunks (< = >)
  			I eqbeg, eqend;
  			partition3(begin, end, *median, pred, &eqbeg, &eqend);
  
  			// loop on larger half
  			if (eqbeg - begin > end - eqend)
  			{
  				sort(eqend, end, pred);
  				end = eqbeg;
  			}
  			else
  			{
  				sort(begin, eqbeg, pred);
  				begin = eqend;
  			}
  		}
  
  		// insertion sort small chunk
  		insertion_sort(begin, end, pred);
  	}
  PUGI__NS_END
  
  // Allocator used for AST and evaluation stacks
  PUGI__NS_BEGIN
  	static const size_t xpath_memory_page_size =
  	#ifdef PUGIXML_MEMORY_XPATH_PAGE_SIZE
  		PUGIXML_MEMORY_XPATH_PAGE_SIZE
  	#else
  		4096
  	#endif
  		;
  
  	static const uintptr_t xpath_memory_block_alignment = sizeof(double) > sizeof(void*) ? sizeof(double) : sizeof(void*);
  
  	struct xpath_memory_block
  	{
  		xpath_memory_block* next;
  		size_t capacity;
  
  		union
  		{
  			char data[xpath_memory_page_size];
  			double alignment;
  		};
  	};
  
  	struct xpath_allocator
  	{
  		xpath_memory_block* _root;
  		size_t _root_size;
  		bool* _error;
  
  		xpath_allocator(xpath_memory_block* root, bool* error = 0): _root(root), _root_size(0), _error(error)
  		{
  		}
  
  		void* allocate(size_t size)
  		{
  			// round size up to block alignment boundary
  			size = (size + xpath_memory_block_alignment - 1) & ~(xpath_memory_block_alignment - 1);
  
  			if (_root_size + size <= _root->capacity)
  			{
  				void* buf = &_root->data[0] + _root_size;
  				_root_size += size;
  				return buf;
  			}
  			else
  			{
  				// make sure we have at least 1/4th of the page free after allocation to satisfy subsequent allocation requests
  				size_t block_capacity_base = sizeof(_root->data);
  				size_t block_capacity_req = size + block_capacity_base / 4;
  				size_t block_capacity = (block_capacity_base > block_capacity_req) ? block_capacity_base : block_capacity_req;
  
  				size_t block_size = block_capacity + offsetof(xpath_memory_block, data);
  
  				xpath_memory_block* block = static_cast<xpath_memory_block*>(xml_memory::allocate(block_size));
  				if (!block)
  				{
  					if (_error) *_error = true;
  					return 0;
  				}
  
  				block->next = _root;
  				block->capacity = block_capacity;
  
  				_root = block;
  				_root_size = size;
  
  				return block->data;
  			}
  		}
  
  		void* reallocate(void* ptr, size_t old_size, size_t new_size)
  		{
  			// round size up to block alignment boundary
  			old_size = (old_size + xpath_memory_block_alignment - 1) & ~(xpath_memory_block_alignment - 1);
  			new_size = (new_size + xpath_memory_block_alignment - 1) & ~(xpath_memory_block_alignment - 1);
  
  			// we can only reallocate the last object
  			assert(ptr == 0 || static_cast<char*>(ptr) + old_size == &_root->data[0] + _root_size);
  
  			// try to reallocate the object inplace
  			if (ptr && _root_size - old_size + new_size <= _root->capacity)
  			{
  				_root_size = _root_size - old_size + new_size;
  				return ptr;
  			}
  
  			// allocate a new block
  			void* result = allocate(new_size);
  			if (!result) return 0;
  
  			// we have a new block
  			if (ptr)
  			{
  				// copy old data (we only support growing)
  				assert(new_size >= old_size);
  				memcpy(result, ptr, old_size);
  
  				// free the previous page if it had no other objects
  				assert(_root->data == result);
  				assert(_root->next);
  
  				if (_root->next->data == ptr)
  				{
  					// deallocate the whole page, unless it was the first one
  					xpath_memory_block* next = _root->next->next;
  
  					if (next)
  					{
  						xml_memory::deallocate(_root->next);
  						_root->next = next;
  					}
  				}
  			}
  
  			return result;
  		}
  
  		void revert(const xpath_allocator& state)
  		{
  			// free all new pages
  			xpath_memory_block* cur = _root;
  
  			while (cur != state._root)
  			{
  				xpath_memory_block* next = cur->next;
  
  				xml_memory::deallocate(cur);
  
  				cur = next;
  			}
  
  			// restore state
  			_root = state._root;
  			_root_size = state._root_size;
  		}
  
  		void release()
  		{
  			xpath_memory_block* cur = _root;
  			assert(cur);
  
  			while (cur->next)
  			{
  				xpath_memory_block* next = cur->next;
  
  				xml_memory::deallocate(cur);
  
  				cur = next;
  			}
  		}
  	};
  
  	struct xpath_allocator_capture
  	{
  		xpath_allocator_capture(xpath_allocator* alloc): _target(alloc), _state(*alloc)
  		{
  		}
  
  		~xpath_allocator_capture()
  		{
  			_target->revert(_state);
  		}
  
  		xpath_allocator* _target;
  		xpath_allocator _state;
  	};
  
  	struct xpath_stack
  	{
  		xpath_allocator* result;
  		xpath_allocator* temp;
  	};
  
  	struct xpath_stack_data
  	{
  		xpath_memory_block blocks[2];
  		xpath_allocator result;
  		xpath_allocator temp;
  		xpath_stack stack;
  		bool oom;
  
  		xpath_stack_data(): result(blocks + 0, &oom), temp(blocks + 1, &oom), oom(false)
  		{
  			blocks[0].next = blocks[1].next = 0;
  			blocks[0].capacity = blocks[1].capacity = sizeof(blocks[0].data);
  
  			stack.result = &result;
  			stack.temp = &temp;
  		}
  
  		~xpath_stack_data()
  		{
  			result.release();
  			temp.release();
  		}
  	};
  PUGI__NS_END
  
  // String class
  PUGI__NS_BEGIN
  	class xpath_string
  	{
  		const char_t* _buffer;
  		bool _uses_heap;
  		size_t _length_heap;
  
  		static char_t* duplicate_string(const char_t* string, size_t length, xpath_allocator* alloc)
  		{
  			char_t* result = static_cast<char_t*>(alloc->allocate((length + 1) * sizeof(char_t)));
  			if (!result) return 0;
  
  			memcpy(result, string, length * sizeof(char_t));
  			result[length] = 0;
  
  			return result;
  		}
  
  		xpath_string(const char_t* buffer, bool uses_heap_, size_t length_heap): _buffer(buffer), _uses_heap(uses_heap_), _length_heap(length_heap)
  		{
  		}
  
  	public:
  		static xpath_string from_const(const char_t* str)
  		{
  			return xpath_string(str, false, 0);
  		}
  
  		static xpath_string from_heap_preallocated(const char_t* begin, const char_t* end)
  		{
  			assert(begin <= end && *end == 0);
  
  			return xpath_string(begin, true, static_cast<size_t>(end - begin));
  		}
  
  		static xpath_string from_heap(const char_t* begin, const char_t* end, xpath_allocator* alloc)
  		{
  			assert(begin <= end);
  
  			if (begin == end)
  				return xpath_string();
  
  			size_t length = static_cast<size_t>(end - begin);
  			const char_t* data = duplicate_string(begin, length, alloc);
  
  			return data ? xpath_string(data, true, length) : xpath_string();
  		}
  
  		xpath_string(): _buffer(PUGIXML_TEXT("")), _uses_heap(false), _length_heap(0)
  		{
  		}
  
  		void append(const xpath_string& o, xpath_allocator* alloc)
  		{
  			// skip empty sources
  			if (!*o._buffer) return;
  
  			// fast append for constant empty target and constant source
  			if (!*_buffer && !_uses_heap && !o._uses_heap)
  			{
  				_buffer = o._buffer;
  			}
  			else
  			{
  				// need to make heap copy
  				size_t target_length = length();
  				size_t source_length = o.length();
  				size_t result_length = target_length + source_length;
  
  				// allocate new buffer
  				char_t* result = static_cast<char_t*>(alloc->reallocate(_uses_heap ? const_cast<char_t*>(_buffer) : 0, (target_length + 1) * sizeof(char_t), (result_length + 1) * sizeof(char_t)));
  				if (!result) return;
  
  				// append first string to the new buffer in case there was no reallocation
  				if (!_uses_heap) memcpy(result, _buffer, target_length * sizeof(char_t));
  
  				// append second string to the new buffer
  				memcpy(result + target_length, o._buffer, source_length * sizeof(char_t));
  				result[result_length] = 0;
  
  				// finalize
  				_buffer = result;
  				_uses_heap = true;
  				_length_heap = result_length;
  			}
  		}
  
  		const char_t* c_str() const
  		{
  			return _buffer;
  		}
  
  		size_t length() const
  		{
  			return _uses_heap ? _length_heap : strlength(_buffer);
  		}
  
  		char_t* data(xpath_allocator* alloc)
  		{
  			// make private heap copy
  			if (!_uses_heap)
  			{
  				size_t length_ = strlength(_buffer);
  				const char_t* data_ = duplicate_string(_buffer, length_, alloc);
  
  				if (!data_) return 0;
  
  				_buffer = data_;
  				_uses_heap = true;
  				_length_heap = length_;
  			}
  
  			return const_cast<char_t*>(_buffer);
  		}
  
  		bool empty() const
  		{
  			return *_buffer == 0;
  		}
  
  		bool operator==(const xpath_string& o) const
  		{
  			return strequal(_buffer, o._buffer);
  		}
  
  		bool operator!=(const xpath_string& o) const
  		{
  			return !strequal(_buffer, o._buffer);
  		}
  
  		bool uses_heap() const
  		{
  			return _uses_heap;
  		}
  	};
  PUGI__NS_END
  
  PUGI__NS_BEGIN
  	PUGI__FN bool starts_with(const char_t* string, const char_t* pattern)
  	{
  		while (*pattern && *string == *pattern)
  		{
  			string++;
  			pattern++;
  		}
  
  		return *pattern == 0;
  	}
  
  	PUGI__FN const char_t* find_char(const char_t* s, char_t c)
  	{
  	#ifdef PUGIXML_WCHAR_MODE
  		return wcschr(s, c);
  	#else
  		return strchr(s, c);
  	#endif
  	}
  
  	PUGI__FN const char_t* find_substring(const char_t* s, const char_t* p)
  	{
  	#ifdef PUGIXML_WCHAR_MODE
  		// MSVC6 wcsstr bug workaround (if s is empty it always returns 0)
  		return (*p == 0) ? s : wcsstr(s, p);
  	#else
  		return strstr(s, p);
  	#endif
  	}
  
  	// Converts symbol to lower case, if it is an ASCII one
  	PUGI__FN char_t tolower_ascii(char_t ch)
  	{
  		return static_cast<unsigned int>(ch - 'A') < 26 ? static_cast<char_t>(ch | ' ') : ch;
  	}
  
  	PUGI__FN xpath_string string_value(const xpath_node& na, xpath_allocator* alloc)
  	{
  		if (na.attribute())
  			return xpath_string::from_const(na.attribute().value());
  		else
  		{
  			xml_node n = na.node();
  
  			switch (n.type())
  			{
  			case node_pcdata:
  			case node_cdata:
  			case node_comment:
  			case node_pi:
  				return xpath_string::from_const(n.value());
  
  			case node_document:
  			case node_element:
  			{
  				xpath_string result;
  
  				// element nodes can have value if parse_embed_pcdata was used
  				if (n.value()[0])
  					result.append(xpath_string::from_const(n.value()), alloc);
  
  				xml_node cur = n.first_child();
  
  				while (cur && cur != n)
  				{
  					if (cur.type() == node_pcdata || cur.type() == node_cdata)
  						result.append(xpath_string::from_const(cur.value()), alloc);
  
  					if (cur.first_child())
  						cur = cur.first_child();
  					else if (cur.next_sibling())
  						cur = cur.next_sibling();
  					else
  					{
  						while (!cur.next_sibling() && cur != n)
  							cur = cur.parent();
  
  						if (cur != n) cur = cur.next_sibling();
  					}
  				}
  
  				return result;
  			}
  
  			default:
  				return xpath_string();
  			}
  		}
  	}
  
  	PUGI__FN bool node_is_before_sibling(xml_node_struct* ln, xml_node_struct* rn)
  	{
  		assert(ln->parent == rn->parent);
  
  		// there is no common ancestor (the shared parent is null), nodes are from different documents
  		if (!ln->parent) return ln < rn;
  
  		// determine sibling order
  		xml_node_struct* ls = ln;
  		xml_node_struct* rs = rn;
  
  		while (ls && rs)
  		{
  			if (ls == rn) return true;
  			if (rs == ln) return false;
  
  			ls = ls->next_sibling;
  			rs = rs->next_sibling;
  		}
  
  		// if rn sibling chain ended ln must be before rn
  		return !rs;
  	}
  
  	PUGI__FN bool node_is_before(xml_node_struct* ln, xml_node_struct* rn)
  	{
  		// find common ancestor at the same depth, if any
  		xml_node_struct* lp = ln;
  		xml_node_struct* rp = rn;
  
  		while (lp && rp && lp->parent != rp->parent)
  		{
  			lp = lp->parent;
  			rp = rp->parent;
  		}
  
  		// parents are the same!
  		if (lp && rp) return node_is_before_sibling(lp, rp);
  
  		// nodes are at different depths, need to normalize heights
  		bool left_higher = !lp;
  
  		while (lp)
  		{
  			lp = lp->parent;
  			ln = ln->parent;
  		}
  
  		while (rp)
  		{
  			rp = rp->parent;
  			rn = rn->parent;
  		}
  
  		// one node is the ancestor of the other
  		if (ln == rn) return left_higher;
  
  		// find common ancestor... again
  		while (ln->parent != rn->parent)
  		{
  			ln = ln->parent;
  			rn = rn->parent;
  		}
  
  		return node_is_before_sibling(ln, rn);
  	}
  
  	PUGI__FN bool node_is_ancestor(xml_node_struct* parent, xml_node_struct* node)
  	{
  		while (node && node != parent) node = node->parent;
  
  		return parent && node == parent;
  	}
  
  	PUGI__FN const void* document_buffer_order(const xpath_node& xnode)
  	{
  		xml_node_struct* node = xnode.node().internal_object();
  
  		if (node)
  		{
  			if ((get_document(node).header & xml_memory_page_contents_shared_mask) == 0)
  			{
  				if (node->name && (node->header & impl::xml_memory_page_name_allocated_or_shared_mask) == 0) return node->name;
  				if (node->value && (node->header & impl::xml_memory_page_value_allocated_or_shared_mask) == 0) return node->value;
  			}
  
  			return 0;
  		}
  
  		xml_attribute_struct* attr = xnode.attribute().internal_object();
  
  		if (attr)
  		{
  			if ((get_document(attr).header & xml_memory_page_contents_shared_mask) == 0)
  			{
  				if ((attr->header & impl::xml_memory_page_name_allocated_or_shared_mask) == 0) return attr->name;
  				if ((attr->header & impl::xml_memory_page_value_allocated_or_shared_mask) == 0) return attr->value;
  			}
  
  			return 0;
  		}
  
  		return 0;
  	}
  
  	struct document_order_comparator
  	{
  		bool operator()(const xpath_node& lhs, const xpath_node& rhs) const
  		{
  			// optimized document order based check
  			const void* lo = document_buffer_order(lhs);
  			const void* ro = document_buffer_order(rhs);
  
  			if (lo && ro) return lo < ro;
  
  			// slow comparison
  			xml_node ln = lhs.node(), rn = rhs.node();
  
  			// compare attributes
  			if (lhs.attribute() && rhs.attribute())
  			{
  				// shared parent
  				if (lhs.parent() == rhs.parent())
  				{
  					// determine sibling order
  					for (xml_attribute a = lhs.attribute(); a; a = a.next_attribute())
  						if (a == rhs.attribute())
  							return true;
  
  					return false;
  				}
  
  				// compare attribute parents
  				ln = lhs.parent();
  				rn = rhs.parent();
  			}
  			else if (lhs.attribute())
  			{
  				// attributes go after the parent element
  				if (lhs.parent() == rhs.node()) return false;
  
  				ln = lhs.parent();
  			}
  			else if (rhs.attribute())
  			{
  				// attributes go after the parent element
  				if (rhs.parent() == lhs.node()) return true;
  
  				rn = rhs.parent();
  			}
  
  			if (ln == rn) return false;
  
  			if (!ln || !rn) return ln < rn;
  
  			return node_is_before(ln.internal_object(), rn.internal_object());
  		}
  	};
  
  	struct duplicate_comparator
  	{
  		bool operator()(const xpath_node& lhs, const xpath_node& rhs) const
  		{
  			if (lhs.attribute()) return rhs.attribute() ? lhs.attribute() < rhs.attribute() : true;
  			else return rhs.attribute() ? false : lhs.node() < rhs.node();
  		}
  	};
  
  	PUGI__FN double gen_nan()
  	{
  	#if defined(__STDC_IEC_559__) || ((FLT_RADIX - 0 == 2) && (FLT_MAX_EXP - 0 == 128) && (FLT_MANT_DIG - 0 == 24))
  		PUGI__STATIC_ASSERT(sizeof(float) == sizeof(uint32_t));
  		typedef uint32_t UI; // BCC5 workaround
  		union { float f; UI i; } u;
  		u.i = 0x7fc00000;
  		return u.f;
  	#else
  		// fallback
  		const volatile double zero = 0.0;
  		return zero / zero;
  	#endif
  	}
  
  	PUGI__FN bool is_nan(double value)
  	{
  	#if defined(PUGI__MSVC_CRT_VERSION) || defined(__BORLANDC__)
  		return !!_isnan(value);
  	#elif defined(fpclassify) && defined(FP_NAN)
  		return fpclassify(value) == FP_NAN;
  	#else
  		// fallback
  		const volatile double v = value;
  		return v != v;
  	#endif
  	}
  
  	PUGI__FN const char_t* convert_number_to_string_special(double value)
  	{
  	#if defined(PUGI__MSVC_CRT_VERSION) || defined(__BORLANDC__)
  		if (_finite(value)) return (value == 0) ? PUGIXML_TEXT("0") : 0;
  		if (_isnan(value)) return PUGIXML_TEXT("NaN");
  		return value > 0 ? PUGIXML_TEXT("Infinity") : PUGIXML_TEXT("-Infinity");
  	#elif defined(fpclassify) && defined(FP_NAN) && defined(FP_INFINITE) && defined(FP_ZERO)
  		switch (fpclassify(value))
  		{
  		case FP_NAN:
  			return PUGIXML_TEXT("NaN");
  
  		case FP_INFINITE:
  			return value > 0 ? PUGIXML_TEXT("Infinity") : PUGIXML_TEXT("-Infinity");
  
  		case FP_ZERO:
  			return PUGIXML_TEXT("0");
  
  		default:
  			return 0;
  		}
  	#else
  		// fallback
  		const volatile double v = value;
  
  		if (v == 0) return PUGIXML_TEXT("0");
  		if (v != v) return PUGIXML_TEXT("NaN");
  		if (v * 2 == v) return value > 0 ? PUGIXML_TEXT("Infinity") : PUGIXML_TEXT("-Infinity");
  		return 0;
  	#endif
  	}
  
  	PUGI__FN bool convert_number_to_boolean(double value)
  	{
  		return (value != 0 && !is_nan(value));
  	}
  
  	PUGI__FN void truncate_zeros(char* begin, char* end)
  	{
  		while (begin != end && end[-1] == '0') end--;
  
  		*end = 0;
  	}
  
  	// gets mantissa digits in the form of 0.xxxxx with 0. implied and the exponent
  #if defined(PUGI__MSVC_CRT_VERSION) && PUGI__MSVC_CRT_VERSION >= 1400 && !defined(_WIN32_WCE)
  	PUGI__FN void convert_number_to_mantissa_exponent(double value, char (&buffer)[32], char** out_mantissa, int* out_exponent)
  	{
  		// get base values
  		int sign, exponent;
  		_ecvt_s(buffer, sizeof(buffer), value, DBL_DIG + 1, &exponent, &sign);
  
  		// truncate redundant zeros
  		truncate_zeros(buffer, buffer + strlen(buffer));
  
  		// fill results
  		*out_mantissa = buffer;
  		*out_exponent = exponent;
  	}
  #else
  	PUGI__FN void convert_number_to_mantissa_exponent(double value, char (&buffer)[32], char** out_mantissa, int* out_exponent)
  	{
  		// get a scientific notation value with IEEE DBL_DIG decimals
  		PUGI__SNPRINTF(buffer, "%.*e", DBL_DIG, value);
  
  		// get the exponent (possibly negative)
  		char* exponent_string = strchr(buffer, 'e');
  		assert(exponent_string);
  
  		int exponent = atoi(exponent_string + 1);
  
  		// extract mantissa string: skip sign
  		char* mantissa = buffer[0] == '-' ? buffer + 1 : buffer;
  		assert(mantissa[0] != '0' && mantissa[1] == '.');
  
  		// divide mantissa by 10 to eliminate integer part
  		mantissa[1] = mantissa[0];
  		mantissa++;
  		exponent++;
  
  		// remove extra mantissa digits and zero-terminate mantissa
  		truncate_zeros(mantissa, exponent_string);
  
  		// fill results
  		*out_mantissa = mantissa;
  		*out_exponent = exponent;
  	}
  #endif
  
  	PUGI__FN xpath_string convert_number_to_string(double value, xpath_allocator* alloc)
  	{
  		// try special number conversion
  		const char_t* special = convert_number_to_string_special(value);
  		if (special) return xpath_string::from_const(special);
  
  		// get mantissa + exponent form
  		char mantissa_buffer[32];
  
  		char* mantissa;
  		int exponent;
  		convert_number_to_mantissa_exponent(value, mantissa_buffer, &mantissa, &exponent);
  
  		// allocate a buffer of suitable length for the number
  		size_t result_size = strlen(mantissa_buffer) + (exponent > 0 ? exponent : -exponent) + 4;
  		char_t* result = static_cast<char_t*>(alloc->allocate(sizeof(char_t) * result_size));
  		if (!result) return xpath_string();
  
  		// make the number!
  		char_t* s = result;
  
  		// sign
  		if (value < 0) *s++ = '-';
  
  		// integer part
  		if (exponent <= 0)
  		{
  			*s++ = '0';
  		}
  		else
  		{
  			while (exponent > 0)
  			{
  				assert(*mantissa == 0 || static_cast<unsigned int>(*mantissa - '0') <= 9);
  				*s++ = *mantissa ? *mantissa++ : '0';
  				exponent--;
  			}
  		}
  
  		// fractional part
  		if (*mantissa)
  		{
  			// decimal point
  			*s++ = '.';
  
  			// extra zeroes from negative exponent
  			while (exponent < 0)
  			{
  				*s++ = '0';
  				exponent++;
  			}
  
  			// extra mantissa digits
  			while (*mantissa)
  			{
  				assert(static_cast<unsigned int>(*mantissa - '0') <= 9);
  				*s++ = *mantissa++;
  			}
  		}
  
  		// zero-terminate
  		assert(s < result + result_size);
  		*s = 0;
  
  		return xpath_string::from_heap_preallocated(result, s);
  	}
  
  	PUGI__FN bool check_string_to_number_format(const char_t* string)
  	{
  		// parse leading whitespace
  		while (PUGI__IS_CHARTYPE(*string, ct_space)) ++string;
  
  		// parse sign
  		if (*string == '-') ++string;
  
  		if (!*string) return false;
  
  		// if there is no integer part, there should be a decimal part with at least one digit
  		if (!PUGI__IS_CHARTYPEX(string[0], ctx_digit) && (string[0] != '.' || !PUGI__IS_CHARTYPEX(string[1], ctx_digit))) return false;
  
  		// parse integer part
  		while (PUGI__IS_CHARTYPEX(*string, ctx_digit)) ++string;
  
  		// parse decimal part
  		if (*string == '.')
  		{
  			++string;
  
  			while (PUGI__IS_CHARTYPEX(*string, ctx_digit)) ++string;
  		}
  
  		// parse trailing whitespace
  		while (PUGI__IS_CHARTYPE(*string, ct_space)) ++string;
  
  		return *string == 0;
  	}
  
  	PUGI__FN double convert_string_to_number(const char_t* string)
  	{
  		// check string format
  		if (!check_string_to_number_format(string)) return gen_nan();
  
  		// parse string
  	#ifdef PUGIXML_WCHAR_MODE
  		return wcstod(string, 0);
  	#else
  		return strtod(string, 0);
  	#endif
  	}
  
  	PUGI__FN bool convert_string_to_number_scratch(char_t (&buffer)[32], const char_t* begin, const char_t* end, double* out_result)
  	{
  		size_t length = static_cast<size_t>(end - begin);
  		char_t* scratch = buffer;
  
  		if (length >= sizeof(buffer) / sizeof(buffer[0]))
  		{
  			// need to make dummy on-heap copy
  			scratch = static_cast<char_t*>(xml_memory::allocate((length + 1) * sizeof(char_t)));
  			if (!scratch) return false;
  		}
  
  		// copy string to zero-terminated buffer and perform conversion
  		memcpy(scratch, begin, length * sizeof(char_t));
  		scratch[length] = 0;
  
  		*out_result = convert_string_to_number(scratch);
  
  		// free dummy buffer
  		if (scratch != buffer) xml_memory::deallocate(scratch);
  
  		return true;
  	}
  
  	PUGI__FN double round_nearest(double value)
  	{
  		return floor(value + 0.5);
  	}
  
  	PUGI__FN double round_nearest_nzero(double value)
  	{
  		// same as round_nearest, but returns -0 for [-0.5, -0]
  		// ceil is used to differentiate between +0 and -0 (we return -0 for [-0.5, -0] and +0 for +0)
  		return (value >= -0.5 && value <= 0) ? ceil(value) : floor(value + 0.5);
  	}
  
  	PUGI__FN const char_t* qualified_name(const xpath_node& node)
  	{
  		return node.attribute() ? node.attribute().name() : node.node().name();
  	}
  
  	PUGI__FN const char_t* local_name(const xpath_node& node)
  	{
  		const char_t* name = qualified_name(node);
  		const char_t* p = find_char(name, ':');
  
  		return p ? p + 1 : name;
  	}
  
  	struct namespace_uri_predicate
  	{
  		const char_t* prefix;
  		size_t prefix_length;
  
  		namespace_uri_predicate(const char_t* name)
  		{
  			const char_t* pos = find_char(name, ':');
  
  			prefix = pos ? name : 0;
  			prefix_length = pos ? static_cast<size_t>(pos - name) : 0;
  		}
  
  		bool operator()(xml_attribute a) const
  		{
  			const char_t* name = a.name();
  
  			if (!starts_with(name, PUGIXML_TEXT("xmlns"))) return false;
  
  			return prefix ? name[5] == ':' && strequalrange(name + 6, prefix, prefix_length) : name[5] == 0;
  		}
  	};
  
  	PUGI__FN const char_t* namespace_uri(xml_node node)
  	{
  		namespace_uri_predicate pred = node.name();
  
  		xml_node p = node;
  
  		while (p)
  		{
  			xml_attribute a = p.find_attribute(pred);
  
  			if (a) return a.value();
  
  			p = p.parent();
  		}
  
  		return PUGIXML_TEXT("");
  	}
  
  	PUGI__FN const char_t* namespace_uri(xml_attribute attr, xml_node parent)
  	{
  		namespace_uri_predicate pred = attr.name();
  
  		// Default namespace does not apply to attributes
  		if (!pred.prefix) return PUGIXML_TEXT("");
  
  		xml_node p = parent;
  
  		while (p)
  		{
  			xml_attribute a = p.find_attribute(pred);
  
  			if (a) return a.value();
  
  			p = p.parent();
  		}
  
  		return PUGIXML_TEXT("");
  	}
  
  	PUGI__FN const char_t* namespace_uri(const xpath_node& node)
  	{
  		return node.attribute() ? namespace_uri(node.attribute(), node.parent()) : namespace_uri(node.node());
  	}
  
  	PUGI__FN char_t* normalize_space(char_t* buffer)
  	{
  		char_t* write = buffer;
  
  		for (char_t* it = buffer; *it; )
  		{
  			char_t ch = *it++;
  
  			if (PUGI__IS_CHARTYPE(ch, ct_space))
  			{
  				// replace whitespace sequence with single space
  				while (PUGI__IS_CHARTYPE(*it, ct_space)) it++;
  
  				// avoid leading spaces
  				if (write != buffer) *write++ = ' ';
  			}
  			else *write++ = ch;
  		}
  
  		// remove trailing space
  		if (write != buffer && PUGI__IS_CHARTYPE(write[-1], ct_space)) write--;
  
  		// zero-terminate
  		*write = 0;
  
  		return write;
  	}
  
  	PUGI__FN char_t* translate(char_t* buffer, const char_t* from, const char_t* to, size_t to_length)
  	{
  		char_t* write = buffer;
  
  		while (*buffer)
  		{
  			PUGI__DMC_VOLATILE char_t ch = *buffer++;
  
  			const char_t* pos = find_char(from, ch);
  
  			if (!pos)
  				*write++ = ch; // do not process
  			else if (static_cast<size_t>(pos - from) < to_length)
  				*write++ = to[pos - from]; // replace
  		}
  
  		// zero-terminate
  		*write = 0;
  
  		return write;
  	}
  
  	PUGI__FN unsigned char* translate_table_generate(xpath_allocator* alloc, const char_t* from, const char_t* to)
  	{
  		unsigned char table[128] = {0};
  
  		while (*from)
  		{
  			unsigned int fc = static_cast<unsigned int>(*from);
  			unsigned int tc = static_cast<unsigned int>(*to);
  
  			if (fc >= 128 || tc >= 128)
  				return 0;
  
  			// code=128 means "skip character"
  			if (!table[fc])
  				table[fc] = static_cast<unsigned char>(tc ? tc : 128);
  
  			from++;
  			if (tc) to++;
  		}
  
  		for (int i = 0; i < 128; ++i)
  			if (!table[i])
  				table[i] = static_cast<unsigned char>(i);
  
  		void* result = alloc->allocate(sizeof(table));
  		if (!result) return 0;
  
  		memcpy(result, table, sizeof(table));
  
  		return static_cast<unsigned char*>(result);
  	}
  
  	PUGI__FN char_t* translate_table(char_t* buffer, const unsigned char* table)
  	{
  		char_t* write = buffer;
  
  		while (*buffer)
  		{
  			char_t ch = *buffer++;
  			unsigned int index = static_cast<unsigned int>(ch);
  
  			if (index < 128)
  			{
  				unsigned char code = table[index];
  
  				// code=128 means "skip character" (table size is 128 so 128 can be a special value)
  				// this code skips these characters without extra branches
  				*write = static_cast<char_t>(code);
  				write += 1 - (code >> 7);
  			}
  			else
  			{
  				*write++ = ch;
  			}
  		}
  
  		// zero-terminate
  		*write = 0;
  
  		return write;
  	}
  
  	inline bool is_xpath_attribute(const char_t* name)
  	{
  		return !(starts_with(name, PUGIXML_TEXT("xmlns")) && (name[5] == 0 || name[5] == ':'));
  	}
  
  	struct xpath_variable_boolean: xpath_variable
  	{
  		xpath_variable_boolean(): xpath_variable(xpath_type_boolean), value(false)
  		{
  		}
  
  		bool value;
  		char_t name[1];
  	};
  
  	struct xpath_variable_number: xpath_variable
  	{
  		xpath_variable_number(): xpath_variable(xpath_type_number), value(0)
  		{
  		}
  
  		double value;
  		char_t name[1];
  	};
  
  	struct xpath_variable_string: xpath_variable
  	{
  		xpath_variable_string(): xpath_variable(xpath_type_string), value(0)
  		{
  		}
  
  		~xpath_variable_string()
  		{
  			if (value) xml_memory::deallocate(value);
  		}
  
  		char_t* value;
  		char_t name[1];
  	};
  
  	struct xpath_variable_node_set: xpath_variable
  	{
  		xpath_variable_node_set(): xpath_variable(xpath_type_node_set)
  		{
  		}
  
  		xpath_node_set value;
  		char_t name[1];
  	};
  
  	static const xpath_node_set dummy_node_set;
  
  	PUGI__FN PUGI__UNSIGNED_OVERFLOW unsigned int hash_string(const char_t* str)
  	{
  		// Jenkins one-at-a-time hash (http://en.wikipedia.org/wiki/Jenkins_hash_function#one-at-a-time)
  		unsigned int result = 0;
  
  		while (*str)
  		{
  			result += static_cast<unsigned int>(*str++);
  			result += result << 10;
  			result ^= result >> 6;
  		}
  
  		result += result << 3;
  		result ^= result >> 11;
  		result += result << 15;
  
  		return result;
  	}
  
  	template <typename T> PUGI__FN T* new_xpath_variable(const char_t* name)
  	{
  		size_t length = strlength(name);
  		if (length == 0) return 0; // empty variable names are invalid
  
  		// $$ we can't use offsetof(T, name) because T is non-POD, so we just allocate additional length characters
  		void* memory = xml_memory::allocate(sizeof(T) + length * sizeof(char_t));
  		if (!memory) return 0;
  
  		T* result = new (memory) T();
  
  		memcpy(result->name, name, (length + 1) * sizeof(char_t));
  
  		return result;
  	}
  
  	PUGI__FN xpath_variable* new_xpath_variable(xpath_value_type type, const char_t* name)
  	{
  		switch (type)
  		{
  		case xpath_type_node_set:
  			return new_xpath_variable<xpath_variable_node_set>(name);
  
  		case xpath_type_number:
  			return new_xpath_variable<xpath_variable_number>(name);
  
  		case xpath_type_string:
  			return new_xpath_variable<xpath_variable_string>(name);
  
  		case xpath_type_boolean:
  			return new_xpath_variable<xpath_variable_boolean>(name);
  
  		default:
  			return 0;
  		}
  	}
  
  	template <typename T> PUGI__FN void delete_xpath_variable(T* var)
  	{
  		var->~T();
  		xml_memory::deallocate(var);
  	}
  
  	PUGI__FN void delete_xpath_variable(xpath_value_type type, xpath_variable* var)
  	{
  		switch (type)
  		{
  		case xpath_type_node_set:
  			delete_xpath_variable(static_cast<xpath_variable_node_set*>(var));
  			break;
  
  		case xpath_type_number:
  			delete_xpath_variable(static_cast<xpath_variable_number*>(var));
  			break;
  
  		case xpath_type_string:
  			delete_xpath_variable(static_cast<xpath_variable_string*>(var));
  			break;
  
  		case xpath_type_boolean:
  			delete_xpath_variable(static_cast<xpath_variable_boolean*>(var));
  			break;
  
  		default:
  			assert(false && "Invalid variable type"); // unreachable
  		}
  	}
  
  	PUGI__FN bool copy_xpath_variable(xpath_variable* lhs, const xpath_variable* rhs)
  	{
  		switch (rhs->type())
  		{
  		case xpath_type_node_set:
  			return lhs->set(static_cast<const xpath_variable_node_set*>(rhs)->value);
  
  		case xpath_type_number:
  			return lhs->set(static_cast<const xpath_variable_number*>(rhs)->value);
  
  		case xpath_type_string:
  			return lhs->set(static_cast<const xpath_variable_string*>(rhs)->value);
  
  		case xpath_type_boolean:
  			return lhs->set(static_cast<const xpath_variable_boolean*>(rhs)->value);
  
  		default:
  			assert(false && "Invalid variable type"); // unreachable
  			return false;
  		}
  	}
  
  	PUGI__FN bool get_variable_scratch(char_t (&buffer)[32], xpath_variable_set* set, const char_t* begin, const char_t* end, xpath_variable** out_result)
  	{
  		size_t length = static_cast<size_t>(end - begin);
  		char_t* scratch = buffer;
  
  		if (length >= sizeof(buffer) / sizeof(buffer[0]))
  		{
  			// need to make dummy on-heap copy
  			scratch = static_cast<char_t*>(xml_memory::allocate((length + 1) * sizeof(char_t)));
  			if (!scratch) return false;
  		}
  
  		// copy string to zero-terminated buffer and perform lookup
  		memcpy(scratch, begin, length * sizeof(char_t));
  		scratch[length] = 0;
  
  		*out_result = set->get(scratch);
  
  		// free dummy buffer
  		if (scratch != buffer) xml_memory::deallocate(scratch);
  
  		return true;
  	}
  PUGI__NS_END
  
  // Internal node set class
  PUGI__NS_BEGIN
  	PUGI__FN xpath_node_set::type_t xpath_get_order(const xpath_node* begin, const xpath_node* end)
  	{
  		if (end - begin < 2)
  			return xpath_node_set::type_sorted;
  
  		document_order_comparator cmp;
  
  		bool first = cmp(begin[0], begin[1]);
  
  		for (const xpath_node* it = begin + 1; it + 1 < end; ++it)
  			if (cmp(it[0], it[1]) != first)
  				return xpath_node_set::type_unsorted;
  
  		return first ? xpath_node_set::type_sorted : xpath_node_set::type_sorted_reverse;
  	}
  
  	PUGI__FN xpath_node_set::type_t xpath_sort(xpath_node* begin, xpath_node* end, xpath_node_set::type_t type, bool rev)
  	{
  		xpath_node_set::type_t order = rev ? xpath_node_set::type_sorted_reverse : xpath_node_set::type_sorted;
  
  		if (type == xpath_node_set::type_unsorted)
  		{
  			xpath_node_set::type_t sorted = xpath_get_order(begin, end);
  
  			if (sorted == xpath_node_set::type_unsorted)
  			{
  				sort(begin, end, document_order_comparator());
  
  				type = xpath_node_set::type_sorted;
  			}
  			else
  				type = sorted;
  		}
  
  		if (type != order) reverse(begin, end);
  
  		return order;
  	}
  
  	PUGI__FN xpath_node xpath_first(const xpath_node* begin, const xpath_node* end, xpath_node_set::type_t type)
  	{
  		if (begin == end) return xpath_node();
  
  		switch (type)
  		{
  		case xpath_node_set::type_sorted:
  			return *begin;
  
  		case xpath_node_set::type_sorted_reverse:
  			return *(end - 1);
  
  		case xpath_node_set::type_unsorted:
  			return *min_element(begin, end, document_order_comparator());
  
  		default:
  			assert(false && "Invalid node set type"); // unreachable
  			return xpath_node();
  		}
  	}
  
  	class xpath_node_set_raw
  	{
  		xpath_node_set::type_t _type;
  
  		xpath_node* _begin;
  		xpath_node* _end;
  		xpath_node* _eos;
  
  	public:
  		xpath_node_set_raw(): _type(xpath_node_set::type_unsorted), _begin(0), _end(0), _eos(0)
  		{
  		}
  
  		xpath_node* begin() const
  		{
  			return _begin;
  		}
  
  		xpath_node* end() const
  		{
  			return _end;
  		}
  
  		bool empty() const
  		{
  			return _begin == _end;
  		}
  
  		size_t size() const
  		{
  			return static_cast<size_t>(_end - _begin);
  		}
  
  		xpath_node first() const
  		{
  			return xpath_first(_begin, _end, _type);
  		}
  
  		void push_back_grow(const xpath_node& node, xpath_allocator* alloc);
  
  		void push_back(const xpath_node& node, xpath_allocator* alloc)
  		{
  			if (_end != _eos)
  				*_end++ = node;
  			else
  				push_back_grow(node, alloc);
  		}
  
  		void append(const xpath_node* begin_, const xpath_node* end_, xpath_allocator* alloc)
  		{
  			if (begin_ == end_) return;
  
  			size_t size_ = static_cast<size_t>(_end - _begin);
  			size_t capacity = static_cast<size_t>(_eos - _begin);
  			size_t count = static_cast<size_t>(end_ - begin_);
  
  			if (size_ + count > capacity)
  			{
  				// reallocate the old array or allocate a new one
  				xpath_node* data = static_cast<xpath_node*>(alloc->reallocate(_begin, capacity * sizeof(xpath_node), (size_ + count) * sizeof(xpath_node)));
  				if (!data) return;
  
  				// finalize
  				_begin = data;
  				_end = data + size_;
  				_eos = data + size_ + count;
  			}
  
  			memcpy(_end, begin_, count * sizeof(xpath_node));
  			_end += count;
  		}
  
  		void sort_do()
  		{
  			_type = xpath_sort(_begin, _end, _type, false);
  		}
  
  		void truncate(xpath_node* pos)
  		{
  			assert(_begin <= pos && pos <= _end);
  
  			_end = pos;
  		}
  
  		void remove_duplicates()
  		{
  			if (_type == xpath_node_set::type_unsorted)
  				sort(_begin, _end, duplicate_comparator());
  
  			_end = unique(_begin, _end);
  		}
  
  		xpath_node_set::type_t type() const
  		{
  			return _type;
  		}
  
  		void set_type(xpath_node_set::type_t value)
  		{
  			_type = value;
  		}
  	};
  
  	PUGI__FN_NO_INLINE void xpath_node_set_raw::push_back_grow(const xpath_node& node, xpath_allocator* alloc)
  	{
  		size_t capacity = static_cast<size_t>(_eos - _begin);
  
  		// get new capacity (1.5x rule)
  		size_t new_capacity = capacity + capacity / 2 + 1;
  
  		// reallocate the old array or allocate a new one
  		xpath_node* data = static_cast<xpath_node*>(alloc->reallocate(_begin, capacity * sizeof(xpath_node), new_capacity * sizeof(xpath_node)));
  		if (!data) return;
  
  		// finalize
  		_begin = data;
  		_end = data + capacity;
  		_eos = data + new_capacity;
  
  		// push
  		*_end++ = node;
  	}
  PUGI__NS_END
  
  PUGI__NS_BEGIN
  	struct xpath_context
  	{
  		xpath_node n;
  		size_t position, size;
  
  		xpath_context(const xpath_node& n_, size_t position_, size_t size_): n(n_), position(position_), size(size_)
  		{
  		}
  	};
  
  	enum lexeme_t
  	{
  		lex_none = 0,
  		lex_equal,
  		lex_not_equal,
  		lex_less,
  		lex_greater,
  		lex_less_or_equal,
  		lex_greater_or_equal,
  		lex_plus,
  		lex_minus,
  		lex_multiply,
  		lex_union,
  		lex_var_ref,
  		lex_open_brace,
  		lex_close_brace,
  		lex_quoted_string,
  		lex_number,
  		lex_slash,
  		lex_double_slash,
  		lex_open_square_brace,
  		lex_close_square_brace,
  		lex_string,
  		lex_comma,
  		lex_axis_attribute,
  		lex_dot,
  		lex_double_dot,
  		lex_double_colon,
  		lex_eof
  	};
  
  	struct xpath_lexer_string
  	{
  		const char_t* begin;
  		const char_t* end;
  
  		xpath_lexer_string(): begin(0), end(0)
  		{
  		}
  
  		bool operator==(const char_t* other) const
  		{
  			size_t length = static_cast<size_t>(end - begin);
  
  			return strequalrange(other, begin, length);
  		}
  	};
  
  	class xpath_lexer
  	{
  		const char_t* _cur;
  		const char_t* _cur_lexeme_pos;
  		xpath_lexer_string _cur_lexeme_contents;
  
  		lexeme_t _cur_lexeme;
  
  	public:
  		explicit xpath_lexer(const char_t* query): _cur(query)
  		{
  			next();
  		}
  
  		const char_t* state() const
  		{
  			return _cur;
  		}
  
  		void next()
  		{
  			const char_t* cur = _cur;
  
  			while (PUGI__IS_CHARTYPE(*cur, ct_space)) ++cur;
  
  			// save lexeme position for error reporting
  			_cur_lexeme_pos = cur;
  
  			switch (*cur)
  			{
  			case 0:
  				_cur_lexeme = lex_eof;
  				break;
  
  			case '>':
  				if (*(cur+1) == '=')
  				{
  					cur += 2;
  					_cur_lexeme = lex_greater_or_equal;
  				}
  				else
  				{
  					cur += 1;
  					_cur_lexeme = lex_greater;
  				}
  				break;
  
  			case '<':
  				if (*(cur+1) == '=')
  				{
  					cur += 2;
  					_cur_lexeme = lex_less_or_equal;
  				}
  				else
  				{
  					cur += 1;
  					_cur_lexeme = lex_less;
  				}
  				break;
  
  			case '!':
  				if (*(cur+1) == '=')
  				{
  					cur += 2;
  					_cur_lexeme = lex_not_equal;
  				}
  				else
  				{
  					_cur_lexeme = lex_none;
  				}
  				break;
  
  			case '=':
  				cur += 1;
  				_cur_lexeme = lex_equal;
  
  				break;
  
  			case '+':
  				cur += 1;
  				_cur_lexeme = lex_plus;
  
  				break;
  
  			case '-':
  				cur += 1;
  				_cur_lexeme = lex_minus;
  
  				break;
  
  			case '*':
  				cur += 1;
  				_cur_lexeme = lex_multiply;
  
  				break;
  
  			case '|':
  				cur += 1;
  				_cur_lexeme = lex_union;
  
  				break;
  
  			case '$':
  				cur += 1;
  
  				if (PUGI__IS_CHARTYPEX(*cur, ctx_start_symbol))
  				{
  					_cur_lexeme_contents.begin = cur;
  
  					while (PUGI__IS_CHARTYPEX(*cur, ctx_symbol)) cur++;
  
  					if (cur[0] == ':' && PUGI__IS_CHARTYPEX(cur[1], ctx_symbol)) // qname
  					{
  						cur++; // :
  
  						while (PUGI__IS_CHARTYPEX(*cur, ctx_symbol)) cur++;
  					}
  
  					_cur_lexeme_contents.end = cur;
  
  					_cur_lexeme = lex_var_ref;
  				}
  				else
  				{
  					_cur_lexeme = lex_none;
  				}
  
  				break;
  
  			case '(':
  				cur += 1;
  				_cur_lexeme = lex_open_brace;
  
  				break;
  
  			case ')':
  				cur += 1;
  				_cur_lexeme = lex_close_brace;
  
  				break;
  
  			case '[':
  				cur += 1;
  				_cur_lexeme = lex_open_square_brace;
  
  				break;
  
  			case ']':
  				cur += 1;
  				_cur_lexeme = lex_close_square_brace;
  
  				break;
  
  			case ',':
  				cur += 1;
  				_cur_lexeme = lex_comma;
  
  				break;
  
  			case '/':
  				if (*(cur+1) == '/')
  				{
  					cur += 2;
  					_cur_lexeme = lex_double_slash;
  				}
  				else
  				{
  					cur += 1;
  					_cur_lexeme = lex_slash;
  				}
  				break;
  
  			case '.':
  				if (*(cur+1) == '.')
  				{
  					cur += 2;
  					_cur_lexeme = lex_double_dot;
  				}
  				else if (PUGI__IS_CHARTYPEX(*(cur+1), ctx_digit))
  				{
  					_cur_lexeme_contents.begin = cur; // .
  
  					++cur;
  
  					while (PUGI__IS_CHARTYPEX(*cur, ctx_digit)) cur++;
  
  					_cur_lexeme_contents.end = cur;
  
  					_cur_lexeme = lex_number;
  				}
  				else
  				{
  					cur += 1;
  					_cur_lexeme = lex_dot;
  				}
  				break;
  
  			case '@':
  				cur += 1;
  				_cur_lexeme = lex_axis_attribute;
  
  				break;
  
  			case '"':
  			case '\'':
  			{
  				char_t terminator = *cur;
  
  				++cur;
  
  				_cur_lexeme_contents.begin = cur;
  				while (*cur && *cur != terminator) cur++;
  				_cur_lexeme_contents.end = cur;
  
  				if (!*cur)
  					_cur_lexeme = lex_none;
  				else
  				{
  					cur += 1;
  					_cur_lexeme = lex_quoted_string;
  				}
  
  				break;
  			}
  
  			case ':':
  				if (*(cur+1) == ':')
  				{
  					cur += 2;
  					_cur_lexeme = lex_double_colon;
  				}
  				else
  				{
  					_cur_lexeme = lex_none;
  				}
  				break;
  
  			default:
  				if (PUGI__IS_CHARTYPEX(*cur, ctx_digit))
  				{
  					_cur_lexeme_contents.begin = cur;
  
  					while (PUGI__IS_CHARTYPEX(*cur, ctx_digit)) cur++;
  
  					if (*cur == '.')
  					{
  						cur++;
  
  						while (PUGI__IS_CHARTYPEX(*cur, ctx_digit)) cur++;
  					}
  
  					_cur_lexeme_contents.end = cur;
  
  					_cur_lexeme = lex_number;
  				}
  				else if (PUGI__IS_CHARTYPEX(*cur, ctx_start_symbol))
  				{
  					_cur_lexeme_contents.begin = cur;
  
  					while (PUGI__IS_CHARTYPEX(*cur, ctx_symbol)) cur++;
  
  					if (cur[0] == ':')
  					{
  						if (cur[1] == '*') // namespace test ncname:*
  						{
  							cur += 2; // :*
  						}
  						else if (PUGI__IS_CHARTYPEX(cur[1], ctx_symbol)) // namespace test qname
  						{
  							cur++; // :
  
  							while (PUGI__IS_CHARTYPEX(*cur, ctx_symbol)) cur++;
  						}
  					}
  
  					_cur_lexeme_contents.end = cur;
  
  					_cur_lexeme = lex_string;
  				}
  				else
  				{
  					_cur_lexeme = lex_none;
  				}
  			}
  
  			_cur = cur;
  		}
  
  		lexeme_t current() const
  		{
  			return _cur_lexeme;
  		}
  
  		const char_t* current_pos() const
  		{
  			return _cur_lexeme_pos;
  		}
  
  		const xpath_lexer_string& contents() const
  		{
  			assert(_cur_lexeme == lex_var_ref || _cur_lexeme == lex_number || _cur_lexeme == lex_string || _cur_lexeme == lex_quoted_string);
  
  			return _cur_lexeme_contents;
  		}
  	};
  
  	enum ast_type_t
  	{
  		ast_unknown,
  		ast_op_or,						// left or right
  		ast_op_and,						// left and right
  		ast_op_equal,					// left = right
  		ast_op_not_equal,				// left != right
  		ast_op_less,					// left < right
  		ast_op_greater,					// left > right
  		ast_op_less_or_equal,			// left <= right
  		ast_op_greater_or_equal,		// left >= right
  		ast_op_add,						// left + right
  		ast_op_subtract,				// left - right
  		ast_op_multiply,				// left * right
  		ast_op_divide,					// left / right
  		ast_op_mod,						// left % right
  		ast_op_negate,					// left - right
  		ast_op_union,					// left | right
  		ast_predicate,					// apply predicate to set; next points to next predicate
  		ast_filter,						// select * from left where right
  		ast_string_constant,			// string constant
  		ast_number_constant,			// number constant
  		ast_variable,					// variable
  		ast_func_last,					// last()
  		ast_func_position,				// position()
  		ast_func_count,					// count(left)
  		ast_func_id,					// id(left)
  		ast_func_local_name_0,			// local-name()
  		ast_func_local_name_1,			// local-name(left)
  		ast_func_namespace_uri_0,		// namespace-uri()
  		ast_func_namespace_uri_1,		// namespace-uri(left)
  		ast_func_name_0,				// name()
  		ast_func_name_1,				// name(left)
  		ast_func_string_0,				// string()
  		ast_func_string_1,				// string(left)
  		ast_func_concat,				// concat(left, right, siblings)
  		ast_func_starts_with,			// starts_with(left, right)
  		ast_func_contains,				// contains(left, right)
  		ast_func_substring_before,		// substring-before(left, right)
  		ast_func_substring_after,		// substring-after(left, right)
  		ast_func_substring_2,			// substring(left, right)
  		ast_func_substring_3,			// substring(left, right, third)
  		ast_func_string_length_0,		// string-length()
  		ast_func_string_length_1,		// string-length(left)
  		ast_func_normalize_space_0,		// normalize-space()
  		ast_func_normalize_space_1,		// normalize-space(left)
  		ast_func_translate,				// translate(left, right, third)
  		ast_func_boolean,				// boolean(left)
  		ast_func_not,					// not(left)
  		ast_func_true,					// true()
  		ast_func_false,					// false()
  		ast_func_lang,					// lang(left)
  		ast_func_number_0,				// number()
  		ast_func_number_1,				// number(left)
  		ast_func_sum,					// sum(left)
  		ast_func_floor,					// floor(left)
  		ast_func_ceiling,				// ceiling(left)
  		ast_func_round,					// round(left)
  		ast_step,						// process set left with step
  		ast_step_root,					// select root node
  
  		ast_opt_translate_table,		// translate(left, right, third) where right/third are constants
  		ast_opt_compare_attribute		// @name = 'string'
  	};
  
  	enum axis_t
  	{
  		axis_ancestor,
  		axis_ancestor_or_self,
  		axis_attribute,
  		axis_child,
  		axis_descendant,
  		axis_descendant_or_self,
  		axis_following,
  		axis_following_sibling,
  		axis_namespace,
  		axis_parent,
  		axis_preceding,
  		axis_preceding_sibling,
  		axis_self
  	};
  
  	enum nodetest_t
  	{
  		nodetest_none,
  		nodetest_name,
  		nodetest_type_node,
  		nodetest_type_comment,
  		nodetest_type_pi,
  		nodetest_type_text,
  		nodetest_pi,
  		nodetest_all,
  		nodetest_all_in_namespace
  	};
  
  	enum predicate_t
  	{
  		predicate_default,
  		predicate_posinv,
  		predicate_constant,
  		predicate_constant_one
  	};
  
  	enum nodeset_eval_t
  	{
  		nodeset_eval_all,
  		nodeset_eval_any,
  		nodeset_eval_first
  	};
  
  	template <axis_t N> struct axis_to_type
  	{
  		static const axis_t axis;
  	};
  
  	template <axis_t N> const axis_t axis_to_type<N>::axis = N;
  
  	class xpath_ast_node
  	{
  	private:
  		// node type
  		char _type;
  		char _rettype;
  
  		// for ast_step
  		char _axis;
  
  		// for ast_step/ast_predicate/ast_filter
  		char _test;
  
  		// tree node structure
  		xpath_ast_node* _left;
  		xpath_ast_node* _right;
  		xpath_ast_node* _next;
  
  		union
  		{
  			// value for ast_string_constant
  			const char_t* string;
  			// value for ast_number_constant
  			double number;
  			// variable for ast_variable
  			xpath_variable* variable;
  			// node test for ast_step (node name/namespace/node type/pi target)
  			const char_t* nodetest;
  			// table for ast_opt_translate_table
  			const unsigned char* table;
  		} _data;
  
  		xpath_ast_node(const xpath_ast_node&);
  		xpath_ast_node& operator=(const xpath_ast_node&);
  
  		template <class Comp> static bool compare_eq(xpath_ast_node* lhs, xpath_ast_node* rhs, const xpath_context& c, const xpath_stack& stack, const Comp& comp)
  		{
  			xpath_value_type lt = lhs->rettype(), rt = rhs->rettype();
  
  			if (lt != xpath_type_node_set && rt != xpath_type_node_set)
  			{
  				if (lt == xpath_type_boolean || rt == xpath_type_boolean)
  					return comp(lhs->eval_boolean(c, stack), rhs->eval_boolean(c, stack));
  				else if (lt == xpath_type_number || rt == xpath_type_number)
  					return comp(lhs->eval_number(c, stack), rhs->eval_number(c, stack));
  				else if (lt == xpath_type_string || rt == xpath_type_string)
  				{
  					xpath_allocator_capture cr(stack.result);
  
  					xpath_string ls = lhs->eval_string(c, stack);
  					xpath_string rs = rhs->eval_string(c, stack);
  
  					return comp(ls, rs);
  				}
  			}
  			else if (lt == xpath_type_node_set && rt == xpath_type_node_set)
  			{
  				xpath_allocator_capture cr(stack.result);
  
  				xpath_node_set_raw ls = lhs->eval_node_set(c, stack, nodeset_eval_all);
  				xpath_node_set_raw rs = rhs->eval_node_set(c, stack, nodeset_eval_all);
  
  				for (const xpath_node* li = ls.begin(); li != ls.end(); ++li)
  					for (const xpath_node* ri = rs.begin(); ri != rs.end(); ++ri)
  					{
  						xpath_allocator_capture cri(stack.result);
  
  						if (comp(string_value(*li, stack.result), string_value(*ri, stack.result)))
  							return true;
  					}
  
  				return false;
  			}
  			else
  			{
  				if (lt == xpath_type_node_set)
  				{
  					swap(lhs, rhs);
  					swap(lt, rt);
  				}
  
  				if (lt == xpath_type_boolean)
  					return comp(lhs->eval_boolean(c, stack), rhs->eval_boolean(c, stack));
  				else if (lt == xpath_type_number)
  				{
  					xpath_allocator_capture cr(stack.result);
  
  					double l = lhs->eval_number(c, stack);
  					xpath_node_set_raw rs = rhs->eval_node_set(c, stack, nodeset_eval_all);
  
  					for (const xpath_node* ri = rs.begin(); ri != rs.end(); ++ri)
  					{
  						xpath_allocator_capture cri(stack.result);
  
  						if (comp(l, convert_string_to_number(string_value(*ri, stack.result).c_str())))
  							return true;
  					}
  
  					return false;
  				}
  				else if (lt == xpath_type_string)
  				{
  					xpath_allocator_capture cr(stack.result);
  
  					xpath_string l = lhs->eval_string(c, stack);
  					xpath_node_set_raw rs = rhs->eval_node_set(c, stack, nodeset_eval_all);
  
  					for (const xpath_node* ri = rs.begin(); ri != rs.end(); ++ri)
  					{
  						xpath_allocator_capture cri(stack.result);
  
  						if (comp(l, string_value(*ri, stack.result)))
  							return true;
  					}
  
  					return false;
  				}
  			}
  
  			assert(false && "Wrong types"); // unreachable
  			return false;
  		}
  
  		static bool eval_once(xpath_node_set::type_t type, nodeset_eval_t eval)
  		{
  			return type == xpath_node_set::type_sorted ? eval != nodeset_eval_all : eval == nodeset_eval_any;
  		}
  
  		template <class Comp> static bool compare_rel(xpath_ast_node* lhs, xpath_ast_node* rhs, const xpath_context& c, const xpath_stack& stack, const Comp& comp)
  		{
  			xpath_value_type lt = lhs->rettype(), rt = rhs->rettype();
  
  			if (lt != xpath_type_node_set && rt != xpath_type_node_set)
  				return comp(lhs->eval_number(c, stack), rhs->eval_number(c, stack));
  			else if (lt == xpath_type_node_set && rt == xpath_type_node_set)
  			{
  				xpath_allocator_capture cr(stack.result);
  
  				xpath_node_set_raw ls = lhs->eval_node_set(c, stack, nodeset_eval_all);
  				xpath_node_set_raw rs = rhs->eval_node_set(c, stack, nodeset_eval_all);
  
  				for (const xpath_node* li = ls.begin(); li != ls.end(); ++li)
  				{
  					xpath_allocator_capture cri(stack.result);
  
  					double l = convert_string_to_number(string_value(*li, stack.result).c_str());
  
  					for (const xpath_node* ri = rs.begin(); ri != rs.end(); ++ri)
  					{
  						xpath_allocator_capture crii(stack.result);
  
  						if (comp(l, convert_string_to_number(string_value(*ri, stack.result).c_str())))
  							return true;
  					}
  				}
  
  				return false;
  			}
  			else if (lt != xpath_type_node_set && rt == xpath_type_node_set)
  			{
  				xpath_allocator_capture cr(stack.result);
  
  				double l = lhs->eval_number(c, stack);
  				xpath_node_set_raw rs = rhs->eval_node_set(c, stack, nodeset_eval_all);
  
  				for (const xpath_node* ri = rs.begin(); ri != rs.end(); ++ri)
  				{
  					xpath_allocator_capture cri(stack.result);
  
  					if (comp(l, convert_string_to_number(string_value(*ri, stack.result).c_str())))
  						return true;
  				}
  
  				return false;
  			}
  			else if (lt == xpath_type_node_set && rt != xpath_type_node_set)
  			{
  				xpath_allocator_capture cr(stack.result);
  
  				xpath_node_set_raw ls = lhs->eval_node_set(c, stack, nodeset_eval_all);
  				double r = rhs->eval_number(c, stack);
  
  				for (const xpath_node* li = ls.begin(); li != ls.end(); ++li)
  				{
  					xpath_allocator_capture cri(stack.result);
  
  					if (comp(convert_string_to_number(string_value(*li, stack.result).c_str()), r))
  						return true;
  				}
  
  				return false;
  			}
  			else
  			{
  				assert(false && "Wrong types"); // unreachable
  				return false;
  			}
  		}
  
  		static void apply_predicate_boolean(xpath_node_set_raw& ns, size_t first, xpath_ast_node* expr, const xpath_stack& stack, bool once)
  		{
  			assert(ns.size() >= first);
  			assert(expr->rettype() != xpath_type_number);
  
  			size_t i = 1;
  			size_t size = ns.size() - first;
  
  			xpath_node* last = ns.begin() + first;
  
  			// remove_if... or well, sort of
  			for (xpath_node* it = last; it != ns.end(); ++it, ++i)
  			{
  				xpath_context c(*it, i, size);
  
  				if (expr->eval_boolean(c, stack))
  				{
  					*last++ = *it;
  
  					if (once) break;
  				}
  			}
  
  			ns.truncate(last);
  		}
  
  		static void apply_predicate_number(xpath_node_set_raw& ns, size_t first, xpath_ast_node* expr, const xpath_stack& stack, bool once)
  		{
  			assert(ns.size() >= first);
  			assert(expr->rettype() == xpath_type_number);
  
  			size_t i = 1;
  			size_t size = ns.size() - first;
  
  			xpath_node* last = ns.begin() + first;
  
  			// remove_if... or well, sort of
  			for (xpath_node* it = last; it != ns.end(); ++it, ++i)
  			{
  				xpath_context c(*it, i, size);
  
  				if (expr->eval_number(c, stack) == i)
  				{
  					*last++ = *it;
  
  					if (once) break;
  				}
  			}
  
  			ns.truncate(last);
  		}
  
  		static void apply_predicate_number_const(xpath_node_set_raw& ns, size_t first, xpath_ast_node* expr, const xpath_stack& stack)
  		{
  			assert(ns.size() >= first);
  			assert(expr->rettype() == xpath_type_number);
  
  			size_t size = ns.size() - first;
  
  			xpath_node* last = ns.begin() + first;
  
  			xpath_context c(xpath_node(), 1, size);
  
  			double er = expr->eval_number(c, stack);
  
  			if (er >= 1.0 && er <= size)
  			{
  				size_t eri = static_cast<size_t>(er);
  
  				if (er == eri)
  				{
  					xpath_node r = last[eri - 1];
  
  					*last++ = r;
  				}
  			}
  
  			ns.truncate(last);
  		}
  
  		void apply_predicate(xpath_node_set_raw& ns, size_t first, const xpath_stack& stack, bool once)
  		{
  			if (ns.size() == first) return;
  
  			assert(_type == ast_filter || _type == ast_predicate);
  
  			if (_test == predicate_constant || _test == predicate_constant_one)
  				apply_predicate_number_const(ns, first, _right, stack);
  			else if (_right->rettype() == xpath_type_number)
  				apply_predicate_number(ns, first, _right, stack, once);
  			else
  				apply_predicate_boolean(ns, first, _right, stack, once);
  		}
  
  		void apply_predicates(xpath_node_set_raw& ns, size_t first, const xpath_stack& stack, nodeset_eval_t eval)
  		{
  			if (ns.size() == first) return;
  
  			bool last_once = eval_once(ns.type(), eval);
  
  			for (xpath_ast_node* pred = _right; pred; pred = pred->_next)
  				pred->apply_predicate(ns, first, stack, !pred->_next && last_once);
  		}
  
  		bool step_push(xpath_node_set_raw& ns, xml_attribute_struct* a, xml_node_struct* parent, xpath_allocator* alloc)
  		{
  			assert(a);
  
  			const char_t* name = a->name ? a->name + 0 : PUGIXML_TEXT("");
  
  			switch (_test)
  			{
  			case nodetest_name:
  				if (strequal(name, _data.nodetest) && is_xpath_attribute(name))
  				{
  					ns.push_back(xpath_node(xml_attribute(a), xml_node(parent)), alloc);
  					return true;
  				}
  				break;
  
  			case nodetest_type_node:
  			case nodetest_all:
  				if (is_xpath_attribute(name))
  				{
  					ns.push_back(xpath_node(xml_attribute(a), xml_node(parent)), alloc);
  					return true;
  				}
  				break;
  
  			case nodetest_all_in_namespace:
  				if (starts_with(name, _data.nodetest) && is_xpath_attribute(name))
  				{
  					ns.push_back(xpath_node(xml_attribute(a), xml_node(parent)), alloc);
  					return true;
  				}
  				break;
  
  			default:
  				;
  			}
  
  			return false;
  		}
  
  		bool step_push(xpath_node_set_raw& ns, xml_node_struct* n, xpath_allocator* alloc)
  		{
  			assert(n);
  
  			xml_node_type type = PUGI__NODETYPE(n);
  
  			switch (_test)
  			{
  			case nodetest_name:
  				if (type == node_element && n->name && strequal(n->name, _data.nodetest))
  				{
  					ns.push_back(xml_node(n), alloc);
  					return true;
  				}
  				break;
  
  			case nodetest_type_node:
  				ns.push_back(xml_node(n), alloc);
  				return true;
  
  			case nodetest_type_comment:
  				if (type == node_comment)
  				{
  					ns.push_back(xml_node(n), alloc);
  					return true;
  				}
  				break;
  
  			case nodetest_type_text:
  				if (type == node_pcdata || type == node_cdata)
  				{
  					ns.push_back(xml_node(n), alloc);
  					return true;
  				}
  				break;
  
  			case nodetest_type_pi:
  				if (type == node_pi)
  				{
  					ns.push_back(xml_node(n), alloc);
  					return true;
  				}
  				break;
  
  			case nodetest_pi:
  				if (type == node_pi && n->name && strequal(n->name, _data.nodetest))
  				{
  					ns.push_back(xml_node(n), alloc);
  					return true;
  				}
  				break;
  
  			case nodetest_all:
  				if (type == node_element)
  				{
  					ns.push_back(xml_node(n), alloc);
  					return true;
  				}
  				break;
  
  			case nodetest_all_in_namespace:
  				if (type == node_element && n->name && starts_with(n->name, _data.nodetest))
  				{
  					ns.push_back(xml_node(n), alloc);
  					return true;
  				}
  				break;
  
  			default:
  				assert(false && "Unknown axis"); // unreachable
  			}
  
  			return false;
  		}
  
  		template <class T> void step_fill(xpath_node_set_raw& ns, xml_node_struct* n, xpath_allocator* alloc, bool once, T)
  		{
  			const axis_t axis = T::axis;
  
  			switch (axis)
  			{
  			case axis_attribute:
  			{
  				for (xml_attribute_struct* a = n->first_attribute; a; a = a->next_attribute)
  					if (step_push(ns, a, n, alloc) & once)
  						return;
  
  				break;
  			}
  
  			case axis_child:
  			{
  				for (xml_node_struct* c = n->first_child; c; c = c->next_sibling)
  					if (step_push(ns, c, alloc) & once)
  						return;
  
  				break;
  			}
  
  			case axis_descendant:
  			case axis_descendant_or_self:
  			{
  				if (axis == axis_descendant_or_self)
  					if (step_push(ns, n, alloc) & once)
  						return;
  
  				xml_node_struct* cur = n->first_child;
  
  				while (cur)
  				{
  					if (step_push(ns, cur, alloc) & once)
  						return;
  
  					if (cur->first_child)
  						cur = cur->first_child;
  					else
  					{
  						while (!cur->next_sibling)
  						{
  							cur = cur->parent;
  
  							if (cur == n) return;
  						}
  
  						cur = cur->next_sibling;
  					}
  				}
  
  				break;
  			}
  
  			case axis_following_sibling:
  			{
  				for (xml_node_struct* c = n->next_sibling; c; c = c->next_sibling)
  					if (step_push(ns, c, alloc) & once)
  						return;
  
  				break;
  			}
  
  			case axis_preceding_sibling:
  			{
  				for (xml_node_struct* c = n->prev_sibling_c; c->next_sibling; c = c->prev_sibling_c)
  					if (step_push(ns, c, alloc) & once)
  						return;
  
  				break;
  			}
  
  			case axis_following:
  			{
  				xml_node_struct* cur = n;
  
  				// exit from this node so that we don't include descendants
  				while (!cur->next_sibling)
  				{
  					cur = cur->parent;
  
  					if (!cur) return;
  				}
  
  				cur = cur->next_sibling;
  
  				while (cur)
  				{
  					if (step_push(ns, cur, alloc) & once)
  						return;
  
  					if (cur->first_child)
  						cur = cur->first_child;
  					else
  					{
  						while (!cur->next_sibling)
  						{
  							cur = cur->parent;
  
  							if (!cur) return;
  						}
  
  						cur = cur->next_sibling;
  					}
  				}
  
  				break;
  			}
  
  			case axis_preceding:
  			{
  				xml_node_struct* cur = n;
  
  				// exit from this node so that we don't include descendants
  				while (!cur->prev_sibling_c->next_sibling)
  				{
  					cur = cur->parent;
  
  					if (!cur) return;
  				}
  
  				cur = cur->prev_sibling_c;
  
  				while (cur)
  				{
  					if (cur->first_child)
  						cur = cur->first_child->prev_sibling_c;
  					else
  					{
  						// leaf node, can't be ancestor
  						if (step_push(ns, cur, alloc) & once)
  							return;
  
  						while (!cur->prev_sibling_c->next_sibling)
  						{
  							cur = cur->parent;
  
  							if (!cur) return;
  
  							if (!node_is_ancestor(cur, n))
  								if (step_push(ns, cur, alloc) & once)
  									return;
  						}
  
  						cur = cur->prev_sibling_c;
  					}
  				}
  
  				break;
  			}
  
  			case axis_ancestor:
  			case axis_ancestor_or_self:
  			{
  				if (axis == axis_ancestor_or_self)
  					if (step_push(ns, n, alloc) & once)
  						return;
  
  				xml_node_struct* cur = n->parent;
  
  				while (cur)
  				{
  					if (step_push(ns, cur, alloc) & once)
  						return;
  
  					cur = cur->parent;
  				}
  
  				break;
  			}
  
  			case axis_self:
  			{
  				step_push(ns, n, alloc);
  
  				break;
  			}
  
  			case axis_parent:
  			{
  				if (n->parent)
  					step_push(ns, n->parent, alloc);
  
  				break;
  			}
  
  			default:
  				assert(false && "Unimplemented axis"); // unreachable
  			}
  		}
  
  		template <class T> void step_fill(xpath_node_set_raw& ns, xml_attribute_struct* a, xml_node_struct* p, xpath_allocator* alloc, bool once, T v)
  		{
  			const axis_t axis = T::axis;
  
  			switch (axis)
  			{
  			case axis_ancestor:
  			case axis_ancestor_or_self:
  			{
  				if (axis == axis_ancestor_or_self && _test == nodetest_type_node) // reject attributes based on principal node type test
  					if (step_push(ns, a, p, alloc) & once)
  						return;
  
  				xml_node_struct* cur = p;
  
  				while (cur)
  				{
  					if (step_push(ns, cur, alloc) & once)
  						return;
  
  					cur = cur->parent;
  				}
  
  				break;
  			}
  
  			case axis_descendant_or_self:
  			case axis_self:
  			{
  				if (_test == nodetest_type_node) // reject attributes based on principal node type test
  					step_push(ns, a, p, alloc);
  
  				break;
  			}
  
  			case axis_following:
  			{
  				xml_node_struct* cur = p;
  
  				while (cur)
  				{
  					if (cur->first_child)
  						cur = cur->first_child;
  					else
  					{
  						while (!cur->next_sibling)
  						{
  							cur = cur->parent;
  
  							if (!cur) return;
  						}
  
  						cur = cur->next_sibling;
  					}
  
  					if (step_push(ns, cur, alloc) & once)
  						return;
  				}
  
  				break;
  			}
  
  			case axis_parent:
  			{
  				step_push(ns, p, alloc);
  
  				break;
  			}
  
  			case axis_preceding:
  			{
  				// preceding:: axis does not include attribute nodes and attribute ancestors (they are the same as parent's ancestors), so we can reuse node preceding
  				step_fill(ns, p, alloc, once, v);
  				break;
  			}
  
  			default:
  				assert(false && "Unimplemented axis"); // unreachable
  			}
  		}
  
  		template <class T> void step_fill(xpath_node_set_raw& ns, const xpath_node& xn, xpath_allocator* alloc, bool once, T v)
  		{
  			const axis_t axis = T::axis;
  			const bool axis_has_attributes = (axis == axis_ancestor || axis == axis_ancestor_or_self || axis == axis_descendant_or_self || axis == axis_following || axis == axis_parent || axis == axis_preceding || axis == axis_self);
  
  			if (xn.node())
  				step_fill(ns, xn.node().internal_object(), alloc, once, v);
  			else if (axis_has_attributes && xn.attribute() && xn.parent())
  				step_fill(ns, xn.attribute().internal_object(), xn.parent().internal_object(), alloc, once, v);
  		}
  
  		template <class T> xpath_node_set_raw step_do(const xpath_context& c, const xpath_stack& stack, nodeset_eval_t eval, T v)
  		{
  			const axis_t axis = T::axis;
  			const bool axis_reverse = (axis == axis_ancestor || axis == axis_ancestor_or_self || axis == axis_preceding || axis == axis_preceding_sibling);
  			const xpath_node_set::type_t axis_type = axis_reverse ? xpath_node_set::type_sorted_reverse : xpath_node_set::type_sorted;
  
  			bool once =
  				(axis == axis_attribute && _test == nodetest_name) ||
  				(!_right && eval_once(axis_type, eval)) ||
  				(_right && !_right->_next && _right->_test == predicate_constant_one);
  
  			xpath_node_set_raw ns;
  			ns.set_type(axis_type);
  
  			if (_left)
  			{
  				xpath_node_set_raw s = _left->eval_node_set(c, stack, nodeset_eval_all);
  
  				// self axis preserves the original order
  				if (axis == axis_self) ns.set_type(s.type());
  
  				for (const xpath_node* it = s.begin(); it != s.end(); ++it)
  				{
  					size_t size = ns.size();
  
  					// in general, all axes generate elements in a particular order, but there is no order guarantee if axis is applied to two nodes
  					if (axis != axis_self && size != 0) ns.set_type(xpath_node_set::type_unsorted);
  
  					step_fill(ns, *it, stack.result, once, v);
  					if (_right) apply_predicates(ns, size, stack, eval);
  				}
  			}
  			else
  			{
  				step_fill(ns, c.n, stack.result, once, v);
  				if (_right) apply_predicates(ns, 0, stack, eval);
  			}
  
  			// child, attribute and self axes always generate unique set of nodes
  			// for other axis, if the set stayed sorted, it stayed unique because the traversal algorithms do not visit the same node twice
  			if (axis != axis_child && axis != axis_attribute && axis != axis_self && ns.type() == xpath_node_set::type_unsorted)
  				ns.remove_duplicates();
  
  			return ns;
  		}
  
  	public:
  		xpath_ast_node(ast_type_t type, xpath_value_type rettype_, const char_t* value):
  			_type(static_cast<char>(type)), _rettype(static_cast<char>(rettype_)), _axis(0), _test(0), _left(0), _right(0), _next(0)
  		{
  			assert(type == ast_string_constant);
  			_data.string = value;
  		}
  
  		xpath_ast_node(ast_type_t type, xpath_value_type rettype_, double value):
  			_type(static_cast<char>(type)), _rettype(static_cast<char>(rettype_)), _axis(0), _test(0), _left(0), _right(0), _next(0)
  		{
  			assert(type == ast_number_constant);
  			_data.number = value;
  		}
  
  		xpath_ast_node(ast_type_t type, xpath_value_type rettype_, xpath_variable* value):
  			_type(static_cast<char>(type)), _rettype(static_cast<char>(rettype_)), _axis(0), _test(0), _left(0), _right(0), _next(0)
  		{
  			assert(type == ast_variable);
  			_data.variable = value;
  		}
  
  		xpath_ast_node(ast_type_t type, xpath_value_type rettype_, xpath_ast_node* left = 0, xpath_ast_node* right = 0):
  			_type(static_cast<char>(type)), _rettype(static_cast<char>(rettype_)), _axis(0), _test(0), _left(left), _right(right), _next(0)
  		{
  		}
  
  		xpath_ast_node(ast_type_t type, xpath_ast_node* left, axis_t axis, nodetest_t test, const char_t* contents):
  			_type(static_cast<char>(type)), _rettype(xpath_type_node_set), _axis(static_cast<char>(axis)), _test(static_cast<char>(test)), _left(left), _right(0), _next(0)
  		{
  			assert(type == ast_step);
  			_data.nodetest = contents;
  		}
  
  		xpath_ast_node(ast_type_t type, xpath_ast_node* left, xpath_ast_node* right, predicate_t test):
  			_type(static_cast<char>(type)), _rettype(xpath_type_node_set), _axis(0), _test(static_cast<char>(test)), _left(left), _right(right), _next(0)
  		{
  			assert(type == ast_filter || type == ast_predicate);
  		}
  
  		void set_next(xpath_ast_node* value)
  		{
  			_next = value;
  		}
  
  		void set_right(xpath_ast_node* value)
  		{
  			_right = value;
  		}
  
  		bool eval_boolean(const xpath_context& c, const xpath_stack& stack)
  		{
  			switch (_type)
  			{
  			case ast_op_or:
  				return _left->eval_boolean(c, stack) || _right->eval_boolean(c, stack);
  
  			case ast_op_and:
  				return _left->eval_boolean(c, stack) && _right->eval_boolean(c, stack);
  
  			case ast_op_equal:
  				return compare_eq(_left, _right, c, stack, equal_to());
  
  			case ast_op_not_equal:
  				return compare_eq(_left, _right, c, stack, not_equal_to());
  
  			case ast_op_less:
  				return compare_rel(_left, _right, c, stack, less());
  
  			case ast_op_greater:
  				return compare_rel(_right, _left, c, stack, less());
  
  			case ast_op_less_or_equal:
  				return compare_rel(_left, _right, c, stack, less_equal());
  
  			case ast_op_greater_or_equal:
  				return compare_rel(_right, _left, c, stack, less_equal());
  
  			case ast_func_starts_with:
  			{
  				xpath_allocator_capture cr(stack.result);
  
  				xpath_string lr = _left->eval_string(c, stack);
  				xpath_string rr = _right->eval_string(c, stack);
  
  				return starts_with(lr.c_str(), rr.c_str());
  			}
  
  			case ast_func_contains:
  			{
  				xpath_allocator_capture cr(stack.result);
  
  				xpath_string lr = _left->eval_string(c, stack);
  				xpath_string rr = _right->eval_string(c, stack);
  
  				return find_substring(lr.c_str(), rr.c_str()) != 0;
  			}
  
  			case ast_func_boolean:
  				return _left->eval_boolean(c, stack);
  
  			case ast_func_not:
  				return !_left->eval_boolean(c, stack);
  
  			case ast_func_true:
  				return true;
  
  			case ast_func_false:
  				return false;
  
  			case ast_func_lang:
  			{
  				if (c.n.attribute()) return false;
  
  				xpath_allocator_capture cr(stack.result);
  
  				xpath_string lang = _left->eval_string(c, stack);
  
  				for (xml_node n = c.n.node(); n; n = n.parent())
  				{
  					xml_attribute a = n.attribute(PUGIXML_TEXT("xml:lang"));
  
  					if (a)
  					{
  						const char_t* value = a.value();
  
  						// strnicmp / strncasecmp is not portable
  						for (const char_t* lit = lang.c_str(); *lit; ++lit)
  						{
  							if (tolower_ascii(*lit) != tolower_ascii(*value)) return false;
  							++value;
  						}
  
  						return *value == 0 || *value == '-';
  					}
  				}
  
  				return false;
  			}
  
  			case ast_opt_compare_attribute:
  			{
  				const char_t* value = (_right->_type == ast_string_constant) ? _right->_data.string : _right->_data.variable->get_string();
  
  				xml_attribute attr = c.n.node().attribute(_left->_data.nodetest);
  
  				return attr && strequal(attr.value(), value) && is_xpath_attribute(attr.name());
  			}
  
  			case ast_variable:
  			{
  				assert(_rettype == _data.variable->type());
  
  				if (_rettype == xpath_type_boolean)
  					return _data.variable->get_boolean();
  			}
  
  			// fallthrough
  			default:
  			{
  				switch (_rettype)
  				{
  				case xpath_type_number:
  					return convert_number_to_boolean(eval_number(c, stack));
  
  				case xpath_type_string:
  				{
  					xpath_allocator_capture cr(stack.result);
  
  					return !eval_string(c, stack).empty();
  				}
  
  				case xpath_type_node_set:
  				{
  					xpath_allocator_capture cr(stack.result);
  
  					return !eval_node_set(c, stack, nodeset_eval_any).empty();
  				}
  
  				default:
  					assert(false && "Wrong expression for return type boolean"); // unreachable
  					return false;
  				}
  			}
  			}
  		}
  
  		double eval_number(const xpath_context& c, const xpath_stack& stack)
  		{
  			switch (_type)
  			{
  			case ast_op_add:
  				return _left->eval_number(c, stack) + _right->eval_number(c, stack);
  
  			case ast_op_subtract:
  				return _left->eval_number(c, stack) - _right->eval_number(c, stack);
  
  			case ast_op_multiply:
  				return _left->eval_number(c, stack) * _right->eval_number(c, stack);
  
  			case ast_op_divide:
  				return _left->eval_number(c, stack) / _right->eval_number(c, stack);
  
  			case ast_op_mod:
  				return fmod(_left->eval_number(c, stack), _right->eval_number(c, stack));
  
  			case ast_op_negate:
  				return -_left->eval_number(c, stack);
  
  			case ast_number_constant:
  				return _data.number;
  
  			case ast_func_last:
  				return static_cast<double>(c.size);
  
  			case ast_func_position:
  				return static_cast<double>(c.position);
  
  			case ast_func_count:
  			{
  				xpath_allocator_capture cr(stack.result);
  
  				return static_cast<double>(_left->eval_node_set(c, stack, nodeset_eval_all).size());
  			}
  
  			case ast_func_string_length_0:
  			{
  				xpath_allocator_capture cr(stack.result);
  
  				return static_cast<double>(string_value(c.n, stack.result).length());
  			}
  
  			case ast_func_string_length_1:
  			{
  				xpath_allocator_capture cr(stack.result);
  
  				return static_cast<double>(_left->eval_string(c, stack).length());
  			}
  
  			case ast_func_number_0:
  			{
  				xpath_allocator_capture cr(stack.result);
  
  				return convert_string_to_number(string_value(c.n, stack.result).c_str());
  			}
  
  			case ast_func_number_1:
  				return _left->eval_number(c, stack);
  
  			case ast_func_sum:
  			{
  				xpath_allocator_capture cr(stack.result);
  
  				double r = 0;
  
  				xpath_node_set_raw ns = _left->eval_node_set(c, stack, nodeset_eval_all);
  
  				for (const xpath_node* it = ns.begin(); it != ns.end(); ++it)
  				{
  					xpath_allocator_capture cri(stack.result);
  
  					r += convert_string_to_number(string_value(*it, stack.result).c_str());
  				}
  
  				return r;
  			}
  
  			case ast_func_floor:
  			{
  				double r = _left->eval_number(c, stack);
  
  				return r == r ? floor(r) : r;
  			}
  
  			case ast_func_ceiling:
  			{
  				double r = _left->eval_number(c, stack);
  
  				return r == r ? ceil(r) : r;
  			}
  
  			case ast_func_round:
  				return round_nearest_nzero(_left->eval_number(c, stack));
  
  			case ast_variable:
  			{
  				assert(_rettype == _data.variable->type());
  
  				if (_rettype == xpath_type_number)
  					return _data.variable->get_number();
  			}
  
  			// fallthrough
  			default:
  			{
  				switch (_rettype)
  				{
  				case xpath_type_boolean:
  					return eval_boolean(c, stack) ? 1 : 0;
  
  				case xpath_type_string:
  				{
  					xpath_allocator_capture cr(stack.result);
  
  					return convert_string_to_number(eval_string(c, stack).c_str());
  				}
  
  				case xpath_type_node_set:
  				{
  					xpath_allocator_capture cr(stack.result);
  
  					return convert_string_to_number(eval_string(c, stack).c_str());
  				}
  
  				default:
  					assert(false && "Wrong expression for return type number"); // unreachable
  					return 0;
  				}
  
  			}
  			}
  		}
  
  		xpath_string eval_string_concat(const xpath_context& c, const xpath_stack& stack)
  		{
  			assert(_type == ast_func_concat);
  
  			xpath_allocator_capture ct(stack.temp);
  
  			// count the string number
  			size_t count = 1;
  			for (xpath_ast_node* nc = _right; nc; nc = nc->_next) count++;
  
  			// allocate a buffer for temporary string objects
  			xpath_string* buffer = static_cast<xpath_string*>(stack.temp->allocate(count * sizeof(xpath_string)));
  			if (!buffer) return xpath_string();
  
  			// evaluate all strings to temporary stack
  			xpath_stack swapped_stack = {stack.temp, stack.result};
  
  			buffer[0] = _left->eval_string(c, swapped_stack);
  
  			size_t pos = 1;
  			for (xpath_ast_node* n = _right; n; n = n->_next, ++pos) buffer[pos] = n->eval_string(c, swapped_stack);
  			assert(pos == count);
  
  			// get total length
  			size_t length = 0;
  			for (size_t i = 0; i < count; ++i) length += buffer[i].length();
  
  			// create final string
  			char_t* result = static_cast<char_t*>(stack.result->allocate((length + 1) * sizeof(char_t)));
  			if (!result) return xpath_string();
  
  			char_t* ri = result;
  
  			for (size_t j = 0; j < count; ++j)
  				for (const char_t* bi = buffer[j].c_str(); *bi; ++bi)
  					*ri++ = *bi;
  
  			*ri = 0;
  
  			return xpath_string::from_heap_preallocated(result, ri);
  		}
  
  		xpath_string eval_string(const xpath_context& c, const xpath_stack& stack)
  		{
  			switch (_type)
  			{
  			case ast_string_constant:
  				return xpath_string::from_const(_data.string);
  
  			case ast_func_local_name_0:
  			{
  				xpath_node na = c.n;
  
  				return xpath_string::from_const(local_name(na));
  			}
  
  			case ast_func_local_name_1:
  			{
  				xpath_allocator_capture cr(stack.result);
  
  				xpath_node_set_raw ns = _left->eval_node_set(c, stack, nodeset_eval_first);
  				xpath_node na = ns.first();
  
  				return xpath_string::from_const(local_name(na));
  			}
  
  			case ast_func_name_0:
  			{
  				xpath_node na = c.n;
  
  				return xpath_string::from_const(qualified_name(na));
  			}
  
  			case ast_func_name_1:
  			{
  				xpath_allocator_capture cr(stack.result);
  
  				xpath_node_set_raw ns = _left->eval_node_set(c, stack, nodeset_eval_first);
  				xpath_node na = ns.first();
  
  				return xpath_string::from_const(qualified_name(na));
  			}
  
  			case ast_func_namespace_uri_0:
  			{
  				xpath_node na = c.n;
  
  				return xpath_string::from_const(namespace_uri(na));
  			}
  
  			case ast_func_namespace_uri_1:
  			{
  				xpath_allocator_capture cr(stack.result);
  
  				xpath_node_set_raw ns = _left->eval_node_set(c, stack, nodeset_eval_first);
  				xpath_node na = ns.first();
  
  				return xpath_string::from_const(namespace_uri(na));
  			}
  
  			case ast_func_string_0:
  				return string_value(c.n, stack.result);
  
  			case ast_func_string_1:
  				return _left->eval_string(c, stack);
  
  			case ast_func_concat:
  				return eval_string_concat(c, stack);
  
  			case ast_func_substring_before:
  			{
  				xpath_allocator_capture cr(stack.temp);
  
  				xpath_stack swapped_stack = {stack.temp, stack.result};
  
  				xpath_string s = _left->eval_string(c, swapped_stack);
  				xpath_string p = _right->eval_string(c, swapped_stack);
  
  				const char_t* pos = find_substring(s.c_str(), p.c_str());
  
  				return pos ? xpath_string::from_heap(s.c_str(), pos, stack.result) : xpath_string();
  			}
  
  			case ast_func_substring_after:
  			{
  				xpath_allocator_capture cr(stack.temp);
  
  				xpath_stack swapped_stack = {stack.temp, stack.result};
  
  				xpath_string s = _left->eval_string(c, swapped_stack);
  				xpath_string p = _right->eval_string(c, swapped_stack);
  
  				const char_t* pos = find_substring(s.c_str(), p.c_str());
  				if (!pos) return xpath_string();
  
  				const char_t* rbegin = pos + p.length();
  				const char_t* rend = s.c_str() + s.length();
  
  				return s.uses_heap() ? xpath_string::from_heap(rbegin, rend, stack.result) : xpath_string::from_const(rbegin);
  			}
  
  			case ast_func_substring_2:
  			{
  				xpath_allocator_capture cr(stack.temp);
  
  				xpath_stack swapped_stack = {stack.temp, stack.result};
  
  				xpath_string s = _left->eval_string(c, swapped_stack);
  				size_t s_length = s.length();
  
  				double first = round_nearest(_right->eval_number(c, stack));
  
  				if (is_nan(first)) return xpath_string(); // NaN
  				else if (first >= s_length + 1) return xpath_string();
  
  				size_t pos = first < 1 ? 1 : static_cast<size_t>(first);
  				assert(1 <= pos && pos <= s_length + 1);
  
  				const char_t* rbegin = s.c_str() + (pos - 1);
  				const char_t* rend = s.c_str() + s.length();
  
  				return s.uses_heap() ? xpath_string::from_heap(rbegin, rend, stack.result) : xpath_string::from_const(rbegin);
  			}
  
  			case ast_func_substring_3:
  			{
  				xpath_allocator_capture cr(stack.temp);
  
  				xpath_stack swapped_stack = {stack.temp, stack.result};
  
  				xpath_string s = _left->eval_string(c, swapped_stack);
  				size_t s_length = s.length();
  
  				double first = round_nearest(_right->eval_number(c, stack));
  				double last = first + round_nearest(_right->_next->eval_number(c, stack));
  
  				if (is_nan(first) || is_nan(last)) return xpath_string();
  				else if (first >= s_length + 1) return xpath_string();
  				else if (first >= last) return xpath_string();
  				else if (last < 1) return xpath_string();
  
  				size_t pos = first < 1 ? 1 : static_cast<size_t>(first);
  				size_t end = last >= s_length + 1 ? s_length + 1 : static_cast<size_t>(last);
  
  				assert(1 <= pos && pos <= end && end <= s_length + 1);
  				const char_t* rbegin = s.c_str() + (pos - 1);
  				const char_t* rend = s.c_str() + (end - 1);
  
  				return (end == s_length + 1 && !s.uses_heap()) ? xpath_string::from_const(rbegin) : xpath_string::from_heap(rbegin, rend, stack.result);
  			}
  
  			case ast_func_normalize_space_0:
  			{
  				xpath_string s = string_value(c.n, stack.result);
  
  				char_t* begin = s.data(stack.result);
  				if (!begin) return xpath_string();
  
  				char_t* end = normalize_space(begin);
  
  				return xpath_string::from_heap_preallocated(begin, end);
  			}
  
  			case ast_func_normalize_space_1:
  			{
  				xpath_string s = _left->eval_string(c, stack);
  
  				char_t* begin = s.data(stack.result);
  				if (!begin) return xpath_string();
  
  				char_t* end = normalize_space(begin);
  
  				return xpath_string::from_heap_preallocated(begin, end);
  			}
  
  			case ast_func_translate:
  			{
  				xpath_allocator_capture cr(stack.temp);
  
  				xpath_stack swapped_stack = {stack.temp, stack.result};
  
  				xpath_string s = _left->eval_string(c, stack);
  				xpath_string from = _right->eval_string(c, swapped_stack);
  				xpath_string to = _right->_next->eval_string(c, swapped_stack);
  
  				char_t* begin = s.data(stack.result);
  				if (!begin) return xpath_string();
  
  				char_t* end = translate(begin, from.c_str(), to.c_str(), to.length());
  
  				return xpath_string::from_heap_preallocated(begin, end);
  			}
  
  			case ast_opt_translate_table:
  			{
  				xpath_string s = _left->eval_string(c, stack);
  
  				char_t* begin = s.data(stack.result);
  				if (!begin) return xpath_string();
  
  				char_t* end = translate_table(begin, _data.table);
  
  				return xpath_string::from_heap_preallocated(begin, end);
  			}
  
  			case ast_variable:
  			{
  				assert(_rettype == _data.variable->type());
  
  				if (_rettype == xpath_type_string)
  					return xpath_string::from_const(_data.variable->get_string());
  			}
  
  			// fallthrough
  			default:
  			{
  				switch (_rettype)
  				{
  				case xpath_type_boolean:
  					return xpath_string::from_const(eval_boolean(c, stack) ? PUGIXML_TEXT("true") : PUGIXML_TEXT("false"));
  
  				case xpath_type_number:
  					return convert_number_to_string(eval_number(c, stack), stack.result);
  
  				case xpath_type_node_set:
  				{
  					xpath_allocator_capture cr(stack.temp);
  
  					xpath_stack swapped_stack = {stack.temp, stack.result};
  
  					xpath_node_set_raw ns = eval_node_set(c, swapped_stack, nodeset_eval_first);
  					return ns.empty() ? xpath_string() : string_value(ns.first(), stack.result);
  				}
  
  				default:
  					assert(false && "Wrong expression for return type string"); // unreachable
  					return xpath_string();
  				}
  			}
  			}
  		}
  
  		xpath_node_set_raw eval_node_set(const xpath_context& c, const xpath_stack& stack, nodeset_eval_t eval)
  		{
  			switch (_type)
  			{
  			case ast_op_union:
  			{
  				xpath_allocator_capture cr(stack.temp);
  
  				xpath_stack swapped_stack = {stack.temp, stack.result};
  
  				xpath_node_set_raw ls = _left->eval_node_set(c, swapped_stack, eval);
  				xpath_node_set_raw rs = _right->eval_node_set(c, stack, eval);
  
  				// we can optimize merging two sorted sets, but this is a very rare operation, so don't bother
  				rs.set_type(xpath_node_set::type_unsorted);
  
  				rs.append(ls.begin(), ls.end(), stack.result);
  				rs.remove_duplicates();
  
  				return rs;
  			}
  
  			case ast_filter:
  			{
  				xpath_node_set_raw set = _left->eval_node_set(c, stack, _test == predicate_constant_one ? nodeset_eval_first : nodeset_eval_all);
  
  				// either expression is a number or it contains position() call; sort by document order
  				if (_test != predicate_posinv) set.sort_do();
  
  				bool once = eval_once(set.type(), eval);
  
  				apply_predicate(set, 0, stack, once);
  
  				return set;
  			}
  
  			case ast_func_id:
  				return xpath_node_set_raw();
  
  			case ast_step:
  			{
  				switch (_axis)
  				{
  				case axis_ancestor:
  					return step_do(c, stack, eval, axis_to_type<axis_ancestor>());
  
  				case axis_ancestor_or_self:
  					return step_do(c, stack, eval, axis_to_type<axis_ancestor_or_self>());
  
  				case axis_attribute:
  					return step_do(c, stack, eval, axis_to_type<axis_attribute>());
  
  				case axis_child:
  					return step_do(c, stack, eval, axis_to_type<axis_child>());
  
  				case axis_descendant:
  					return step_do(c, stack, eval, axis_to_type<axis_descendant>());
  
  				case axis_descendant_or_self:
  					return step_do(c, stack, eval, axis_to_type<axis_descendant_or_self>());
  
  				case axis_following:
  					return step_do(c, stack, eval, axis_to_type<axis_following>());
  
  				case axis_following_sibling:
  					return step_do(c, stack, eval, axis_to_type<axis_following_sibling>());
  
  				case axis_namespace:
  					// namespaced axis is not supported
  					return xpath_node_set_raw();
  
  				case axis_parent:
  					return step_do(c, stack, eval, axis_to_type<axis_parent>());
  
  				case axis_preceding:
  					return step_do(c, stack, eval, axis_to_type<axis_preceding>());
  
  				case axis_preceding_sibling:
  					return step_do(c, stack, eval, axis_to_type<axis_preceding_sibling>());
  
  				case axis_self:
  					return step_do(c, stack, eval, axis_to_type<axis_self>());
  
  				default:
  					assert(false && "Unknown axis"); // unreachable
  					return xpath_node_set_raw();
  				}
  			}
  
  			case ast_step_root:
  			{
  				assert(!_right); // root step can't have any predicates
  
  				xpath_node_set_raw ns;
  
  				ns.set_type(xpath_node_set::type_sorted);
  
  				if (c.n.node()) ns.push_back(c.n.node().root(), stack.result);
  				else if (c.n.attribute()) ns.push_back(c.n.parent().root(), stack.result);
  
  				return ns;
  			}
  
  			case ast_variable:
  			{
  				assert(_rettype == _data.variable->type());
  
  				if (_rettype == xpath_type_node_set)
  				{
  					const xpath_node_set& s = _data.variable->get_node_set();
  
  					xpath_node_set_raw ns;
  
  					ns.set_type(s.type());
  					ns.append(s.begin(), s.end(), stack.result);
  
  					return ns;
  				}
  			}
  
  			// fallthrough
  			default:
  				assert(false && "Wrong expression for return type node set"); // unreachable
  				return xpath_node_set_raw();
  			}
  		}
  
  		void optimize(xpath_allocator* alloc)
  		{
  			if (_left)
  				_left->optimize(alloc);
  
  			if (_right)
  				_right->optimize(alloc);
  
  			if (_next)
  				_next->optimize(alloc);
  
  			optimize_self(alloc);
  		}
  
  		void optimize_self(xpath_allocator* alloc)
  		{
  			// Rewrite [position()=expr] with [expr]
  			// Note that this step has to go before classification to recognize [position()=1]
  			if ((_type == ast_filter || _type == ast_predicate) &&
  				_right->_type == ast_op_equal && _right->_left->_type == ast_func_position && _right->_right->_rettype == xpath_type_number)
  			{
  				_right = _right->_right;
  			}
  
  			// Classify filter/predicate ops to perform various optimizations during evaluation
  			if (_type == ast_filter || _type == ast_predicate)
  			{
  				assert(_test == predicate_default);
  
  				if (_right->_type == ast_number_constant && _right->_data.number == 1.0)
  					_test = predicate_constant_one;
  				else if (_right->_rettype == xpath_type_number && (_right->_type == ast_number_constant || _right->_type == ast_variable || _right->_type == ast_func_last))
  					_test = predicate_constant;
  				else if (_right->_rettype != xpath_type_number && _right->is_posinv_expr())
  					_test = predicate_posinv;
  			}
  
  			// Rewrite descendant-or-self::node()/child::foo with descendant::foo
  			// The former is a full form of //foo, the latter is much faster since it executes the node test immediately
  			// Do a similar kind of rewrite for self/descendant/descendant-or-self axes
  			// Note that we only rewrite positionally invariant steps (//foo[1] != /descendant::foo[1])
  			if (_type == ast_step && (_axis == axis_child || _axis == axis_self || _axis == axis_descendant || _axis == axis_descendant_or_self) && _left &&
  				_left->_type == ast_step && _left->_axis == axis_descendant_or_self && _left->_test == nodetest_type_node && !_left->_right &&
  				is_posinv_step())
  			{
  				if (_axis == axis_child || _axis == axis_descendant)
  					_axis = axis_descendant;
  				else
  					_axis = axis_descendant_or_self;
  
  				_left = _left->_left;
  			}
  
  			// Use optimized lookup table implementation for translate() with constant arguments
  			if (_type == ast_func_translate && _right->_type == ast_string_constant && _right->_next->_type == ast_string_constant)
  			{
  				unsigned char* table = translate_table_generate(alloc, _right->_data.string, _right->_next->_data.string);
  
  				if (table)
  				{
  					_type = ast_opt_translate_table;
  					_data.table = table;
  				}
  			}
  
  			// Use optimized path for @attr = 'value' or @attr = $value
  			if (_type == ast_op_equal &&
  				_left->_type == ast_step && _left->_axis == axis_attribute && _left->_test == nodetest_name && !_left->_left && !_left->_right &&
  				(_right->_type == ast_string_constant || (_right->_type == ast_variable && _right->_rettype == xpath_type_string)))
  			{
  				_type = ast_opt_compare_attribute;
  			}
  		}
  
  		bool is_posinv_expr() const
  		{
  			switch (_type)
  			{
  			case ast_func_position:
  			case ast_func_last:
  				return false;
  
  			case ast_string_constant:
  			case ast_number_constant:
  			case ast_variable:
  				return true;
  
  			case ast_step:
  			case ast_step_root:
  				return true;
  
  			case ast_predicate:
  			case ast_filter:
  				return true;
  
  			default:
  				if (_left && !_left->is_posinv_expr()) return false;
  
  				for (xpath_ast_node* n = _right; n; n = n->_next)
  					if (!n->is_posinv_expr()) return false;
  
  				return true;
  			}
  		}
  
  		bool is_posinv_step() const
  		{
  			assert(_type == ast_step);
  
  			for (xpath_ast_node* n = _right; n; n = n->_next)
  			{
  				assert(n->_type == ast_predicate);
  
  				if (n->_test != predicate_posinv)
  					return false;
  			}
  
  			return true;
  		}
  
  		xpath_value_type rettype() const
  		{
  			return static_cast<xpath_value_type>(_rettype);
  		}
  	};
  
  	struct xpath_parser
  	{
  		xpath_allocator* _alloc;
  		xpath_lexer _lexer;
  
  		const char_t* _query;
  		xpath_variable_set* _variables;
  
  		xpath_parse_result* _result;
  
  		char_t _scratch[32];
  
  		xpath_ast_node* error(const char* message)
  		{
  			_result->error = message;
  			_result->offset = _lexer.current_pos() - _query;
  
  			return 0;
  		}
  
  		xpath_ast_node* error_oom()
  		{
  			assert(_alloc->_error);
  			*_alloc->_error = true;
  
  			return 0;
  		}
  
  		void* alloc_node()
  		{
  			return _alloc->allocate(sizeof(xpath_ast_node));
  		}
  
  		xpath_ast_node* alloc_node(ast_type_t type, xpath_value_type rettype, const char_t* value)
  		{
  			void* memory = alloc_node();
  			return memory ? new (memory) xpath_ast_node(type, rettype, value) : 0;
  		}
  
  		xpath_ast_node* alloc_node(ast_type_t type, xpath_value_type rettype, double value)
  		{
  			void* memory = alloc_node();
  			return memory ? new (memory) xpath_ast_node(type, rettype, value) : 0;
  		}
  
  		xpath_ast_node* alloc_node(ast_type_t type, xpath_value_type rettype, xpath_variable* value)
  		{
  			void* memory = alloc_node();
  			return memory ? new (memory) xpath_ast_node(type, rettype, value) : 0;
  		}
  
  		xpath_ast_node* alloc_node(ast_type_t type, xpath_value_type rettype, xpath_ast_node* left = 0, xpath_ast_node* right = 0)
  		{
  			void* memory = alloc_node();
  			return memory ? new (memory) xpath_ast_node(type, rettype, left, right) : 0;
  		}
  
  		xpath_ast_node* alloc_node(ast_type_t type, xpath_ast_node* left, axis_t axis, nodetest_t test, const char_t* contents)
  		{
  			void* memory = alloc_node();
  			return memory ? new (memory) xpath_ast_node(type, left, axis, test, contents) : 0;
  		}
  
  		xpath_ast_node* alloc_node(ast_type_t type, xpath_ast_node* left, xpath_ast_node* right, predicate_t test)
  		{
  			void* memory = alloc_node();
  			return memory ? new (memory) xpath_ast_node(type, left, right, test) : 0;
  		}
  
  		const char_t* alloc_string(const xpath_lexer_string& value)
  		{
  			if (!value.begin)
  				return PUGIXML_TEXT("");
  
  			size_t length = static_cast<size_t>(value.end - value.begin);
  
  			char_t* c = static_cast<char_t*>(_alloc->allocate((length + 1) * sizeof(char_t)));
  			if (!c) return 0;
  
  			memcpy(c, value.begin, length * sizeof(char_t));
  			c[length] = 0;
  
  			return c;
  		}
  
  		xpath_ast_node* parse_function(const xpath_lexer_string& name, size_t argc, xpath_ast_node* args[2])
  		{
  			switch (name.begin[0])
  			{
  			case 'b':
  				if (name == PUGIXML_TEXT("boolean") && argc == 1)
  					return alloc_node(ast_func_boolean, xpath_type_boolean, args[0]);
  
  				break;
  
  			case 'c':
  				if (name == PUGIXML_TEXT("count") && argc == 1)
  				{
  					if (args[0]->rettype() != xpath_type_node_set) return error("Function has to be applied to node set");
  					return alloc_node(ast_func_count, xpath_type_number, args[0]);
  				}
  				else if (name == PUGIXML_TEXT("contains") && argc == 2)
  					return alloc_node(ast_func_contains, xpath_type_boolean, args[0], args[1]);
  				else if (name == PUGIXML_TEXT("concat") && argc >= 2)
  					return alloc_node(ast_func_concat, xpath_type_string, args[0], args[1]);
  				else if (name == PUGIXML_TEXT("ceiling") && argc == 1)
  					return alloc_node(ast_func_ceiling, xpath_type_number, args[0]);
  
  				break;
  
  			case 'f':
  				if (name == PUGIXML_TEXT("false") && argc == 0)
  					return alloc_node(ast_func_false, xpath_type_boolean);
  				else if (name == PUGIXML_TEXT("floor") && argc == 1)
  					return alloc_node(ast_func_floor, xpath_type_number, args[0]);
  
  				break;
  
  			case 'i':
  				if (name == PUGIXML_TEXT("id") && argc == 1)
  					return alloc_node(ast_func_id, xpath_type_node_set, args[0]);
  
  				break;
  
  			case 'l':
  				if (name == PUGIXML_TEXT("last") && argc == 0)
  					return alloc_node(ast_func_last, xpath_type_number);
  				else if (name == PUGIXML_TEXT("lang") && argc == 1)
  					return alloc_node(ast_func_lang, xpath_type_boolean, args[0]);
  				else if (name == PUGIXML_TEXT("local-name") && argc <= 1)
  				{
  					if (argc == 1 && args[0]->rettype() != xpath_type_node_set) return error("Function has to be applied to node set");
  					return alloc_node(argc == 0 ? ast_func_local_name_0 : ast_func_local_name_1, xpath_type_string, args[0]);
  				}
  
  				break;
  
  			case 'n':
  				if (name == PUGIXML_TEXT("name") && argc <= 1)
  				{
  					if (argc == 1 && args[0]->rettype() != xpath_type_node_set) return error("Function has to be applied to node set");
  					return alloc_node(argc == 0 ? ast_func_name_0 : ast_func_name_1, xpath_type_string, args[0]);
  				}
  				else if (name == PUGIXML_TEXT("namespace-uri") && argc <= 1)
  				{
  					if (argc == 1 && args[0]->rettype() != xpath_type_node_set) return error("Function has to be applied to node set");
  					return alloc_node(argc == 0 ? ast_func_namespace_uri_0 : ast_func_namespace_uri_1, xpath_type_string, args[0]);
  				}
  				else if (name == PUGIXML_TEXT("normalize-space") && argc <= 1)
  					return alloc_node(argc == 0 ? ast_func_normalize_space_0 : ast_func_normalize_space_1, xpath_type_string, args[0], args[1]);
  				else if (name == PUGIXML_TEXT("not") && argc == 1)
  					return alloc_node(ast_func_not, xpath_type_boolean, args[0]);
  				else if (name == PUGIXML_TEXT("number") && argc <= 1)
  					return alloc_node(argc == 0 ? ast_func_number_0 : ast_func_number_1, xpath_type_number, args[0]);
  
  				break;
  
  			case 'p':
  				if (name == PUGIXML_TEXT("position") && argc == 0)
  					return alloc_node(ast_func_position, xpath_type_number);
  
  				break;
  
  			case 'r':
  				if (name == PUGIXML_TEXT("round") && argc == 1)
  					return alloc_node(ast_func_round, xpath_type_number, args[0]);
  
  				break;
  
  			case 's':
  				if (name == PUGIXML_TEXT("string") && argc <= 1)
  					return alloc_node(argc == 0 ? ast_func_string_0 : ast_func_string_1, xpath_type_string, args[0]);
  				else if (name == PUGIXML_TEXT("string-length") && argc <= 1)
  					return alloc_node(argc == 0 ? ast_func_string_length_0 : ast_func_string_length_1, xpath_type_number, args[0]);
  				else if (name == PUGIXML_TEXT("starts-with") && argc == 2)
  					return alloc_node(ast_func_starts_with, xpath_type_boolean, args[0], args[1]);
  				else if (name == PUGIXML_TEXT("substring-before") && argc == 2)
  					return alloc_node(ast_func_substring_before, xpath_type_string, args[0], args[1]);
  				else if (name == PUGIXML_TEXT("substring-after") && argc == 2)
  					return alloc_node(ast_func_substring_after, xpath_type_string, args[0], args[1]);
  				else if (name == PUGIXML_TEXT("substring") && (argc == 2 || argc == 3))
  					return alloc_node(argc == 2 ? ast_func_substring_2 : ast_func_substring_3, xpath_type_string, args[0], args[1]);
  				else if (name == PUGIXML_TEXT("sum") && argc == 1)
  				{
  					if (args[0]->rettype() != xpath_type_node_set) return error("Function has to be applied to node set");
  					return alloc_node(ast_func_sum, xpath_type_number, args[0]);
  				}
  
  				break;
  
  			case 't':
  				if (name == PUGIXML_TEXT("translate") && argc == 3)
  					return alloc_node(ast_func_translate, xpath_type_string, args[0], args[1]);
  				else if (name == PUGIXML_TEXT("true") && argc == 0)
  					return alloc_node(ast_func_true, xpath_type_boolean);
  
  				break;
  
  			default:
  				break;
  			}
  
  			return error("Unrecognized function or wrong parameter count");
  		}
  
  		axis_t parse_axis_name(const xpath_lexer_string& name, bool& specified)
  		{
  			specified = true;
  
  			switch (name.begin[0])
  			{
  			case 'a':
  				if (name == PUGIXML_TEXT("ancestor"))
  					return axis_ancestor;
  				else if (name == PUGIXML_TEXT("ancestor-or-self"))
  					return axis_ancestor_or_self;
  				else if (name == PUGIXML_TEXT("attribute"))
  					return axis_attribute;
  
  				break;
  
  			case 'c':
  				if (name == PUGIXML_TEXT("child"))
  					return axis_child;
  
  				break;
  
  			case 'd':
  				if (name == PUGIXML_TEXT("descendant"))
  					return axis_descendant;
  				else if (name == PUGIXML_TEXT("descendant-or-self"))
  					return axis_descendant_or_self;
  
  				break;
  
  			case 'f':
  				if (name == PUGIXML_TEXT("following"))
  					return axis_following;
  				else if (name == PUGIXML_TEXT("following-sibling"))
  					return axis_following_sibling;
  
  				break;
  
  			case 'n':
  				if (name == PUGIXML_TEXT("namespace"))
  					return axis_namespace;
  
  				break;
  
  			case 'p':
  				if (name == PUGIXML_TEXT("parent"))
  					return axis_parent;
  				else if (name == PUGIXML_TEXT("preceding"))
  					return axis_preceding;
  				else if (name == PUGIXML_TEXT("preceding-sibling"))
  					return axis_preceding_sibling;
  
  				break;
  
  			case 's':
  				if (name == PUGIXML_TEXT("self"))
  					return axis_self;
  
  				break;
  
  			default:
  				break;
  			}
  
  			specified = false;
  			return axis_child;
  		}
  
  		nodetest_t parse_node_test_type(const xpath_lexer_string& name)
  		{
  			switch (name.begin[0])
  			{
  			case 'c':
  				if (name == PUGIXML_TEXT("comment"))
  					return nodetest_type_comment;
  
  				break;
  
  			case 'n':
  				if (name == PUGIXML_TEXT("node"))
  					return nodetest_type_node;
  
  				break;
  
  			case 'p':
  				if (name == PUGIXML_TEXT("processing-instruction"))
  					return nodetest_type_pi;
  
  				break;
  
  			case 't':
  				if (name == PUGIXML_TEXT("text"))
  					return nodetest_type_text;
  
  				break;
  
  			default:
  				break;
  			}
  
  			return nodetest_none;
  		}
  
  		// PrimaryExpr ::= VariableReference | '(' Expr ')' | Literal | Number | FunctionCall
  		xpath_ast_node* parse_primary_expression()
  		{
  			switch (_lexer.current())
  			{
  			case lex_var_ref:
  			{
  				xpath_lexer_string name = _lexer.contents();
  
  				if (!_variables)
  					return error("Unknown variable: variable set is not provided");
  
  				xpath_variable* var = 0;
  				if (!get_variable_scratch(_scratch, _variables, name.begin, name.end, &var))
  					return error_oom();
  
  				if (!var)
  					return error("Unknown variable: variable set does not contain the given name");
  
  				_lexer.next();
  
  				return alloc_node(ast_variable, var->type(), var);
  			}
  
  			case lex_open_brace:
  			{
  				_lexer.next();
  
  				xpath_ast_node* n = parse_expression();
  				if (!n) return 0;
  
  				if (_lexer.current() != lex_close_brace)
  					return error("Expected ')' to match an opening '('");
  
  				_lexer.next();
  
  				return n;
  			}
  
  			case lex_quoted_string:
  			{
  				const char_t* value = alloc_string(_lexer.contents());
  				if (!value) return 0;
  
  				_lexer.next();
  
  				return alloc_node(ast_string_constant, xpath_type_string, value);
  			}
  
  			case lex_number:
  			{
  				double value = 0;
  
  				if (!convert_string_to_number_scratch(_scratch, _lexer.contents().begin, _lexer.contents().end, &value))
  					return error_oom();
  
  				_lexer.next();
  
  				return alloc_node(ast_number_constant, xpath_type_number, value);
  			}
  
  			case lex_string:
  			{
  				xpath_ast_node* args[2] = {0};
  				size_t argc = 0;
  
  				xpath_lexer_string function = _lexer.contents();
  				_lexer.next();
  
  				xpath_ast_node* last_arg = 0;
  
  				if (_lexer.current() != lex_open_brace)
  					return error("Unrecognized function call");
  				_lexer.next();
  
  				while (_lexer.current() != lex_close_brace)
  				{
  					if (argc > 0)
  					{
  						if (_lexer.current() != lex_comma)
  							return error("No comma between function arguments");
  						_lexer.next();
  					}
  
  					xpath_ast_node* n = parse_expression();
  					if (!n) return 0;
  
  					if (argc < 2) args[argc] = n;
  					else last_arg->set_next(n);
  
  					argc++;
  					last_arg = n;
  				}
  
  				_lexer.next();
  
  				return parse_function(function, argc, args);
  			}
  
  			default:
  				return error("Unrecognizable primary expression");
  			}
  		}
  
  		// FilterExpr ::= PrimaryExpr | FilterExpr Predicate
  		// Predicate ::= '[' PredicateExpr ']'
  		// PredicateExpr ::= Expr
  		xpath_ast_node* parse_filter_expression()
  		{
  			xpath_ast_node* n = parse_primary_expression();
  			if (!n) return 0;
  
  			while (_lexer.current() == lex_open_square_brace)
  			{
  				_lexer.next();
  
  				if (n->rettype() != xpath_type_node_set)
  					return error("Predicate has to be applied to node set");
  
  				xpath_ast_node* expr = parse_expression();
  				if (!expr) return 0;
  
  				n = alloc_node(ast_filter, n, expr, predicate_default);
  				if (!n) return 0;
  
  				if (_lexer.current() != lex_close_square_brace)
  					return error("Expected ']' to match an opening '['");
  
  				_lexer.next();
  			}
  
  			return n;
  		}
  
  		// Step ::= AxisSpecifier NodeTest Predicate* | AbbreviatedStep
  		// AxisSpecifier ::= AxisName '::' | '@'?
  		// NodeTest ::= NameTest | NodeType '(' ')' | 'processing-instruction' '(' Literal ')'
  		// NameTest ::= '*' | NCName ':' '*' | QName
  		// AbbreviatedStep ::= '.' | '..'
  		xpath_ast_node* parse_step(xpath_ast_node* set)
  		{
  			if (set && set->rettype() != xpath_type_node_set)
  				return error("Step has to be applied to node set");
  
  			bool axis_specified = false;
  			axis_t axis = axis_child; // implied child axis
  
  			if (_lexer.current() == lex_axis_attribute)
  			{
  				axis = axis_attribute;
  				axis_specified = true;
  
  				_lexer.next();
  			}
  			else if (_lexer.current() == lex_dot)
  			{
  				_lexer.next();
  
  				if (_lexer.current() == lex_open_square_brace)
  					return error("Predicates are not allowed after an abbreviated step");
  
  				return alloc_node(ast_step, set, axis_self, nodetest_type_node, 0);
  			}
  			else if (_lexer.current() == lex_double_dot)
  			{
  				_lexer.next();
  
  				if (_lexer.current() == lex_open_square_brace)
  					return error("Predicates are not allowed after an abbreviated step");
  
  				return alloc_node(ast_step, set, axis_parent, nodetest_type_node, 0);
  			}
  
  			nodetest_t nt_type = nodetest_none;
  			xpath_lexer_string nt_name;
  
  			if (_lexer.current() == lex_string)
  			{
  				// node name test
  				nt_name = _lexer.contents();
  				_lexer.next();
  
  				// was it an axis name?
  				if (_lexer.current() == lex_double_colon)
  				{
  					// parse axis name
  					if (axis_specified)
  						return error("Two axis specifiers in one step");
  
  					axis = parse_axis_name(nt_name, axis_specified);
  
  					if (!axis_specified)
  						return error("Unknown axis");
  
  					// read actual node test
  					_lexer.next();
  
  					if (_lexer.current() == lex_multiply)
  					{
  						nt_type = nodetest_all;
  						nt_name = xpath_lexer_string();
  						_lexer.next();
  					}
  					else if (_lexer.current() == lex_string)
  					{
  						nt_name = _lexer.contents();
  						_lexer.next();
  					}
  					else
  					{
  						return error("Unrecognized node test");
  					}
  				}
  
  				if (nt_type == nodetest_none)
  				{
  					// node type test or processing-instruction
  					if (_lexer.current() == lex_open_brace)
  					{
  						_lexer.next();
  
  						if (_lexer.current() == lex_close_brace)
  						{
  							_lexer.next();
  
  							nt_type = parse_node_test_type(nt_name);
  
  							if (nt_type == nodetest_none)
  								return error("Unrecognized node type");
  
  							nt_name = xpath_lexer_string();
  						}
  						else if (nt_name == PUGIXML_TEXT("processing-instruction"))
  						{
  							if (_lexer.current() != lex_quoted_string)
  								return error("Only literals are allowed as arguments to processing-instruction()");
  
  							nt_type = nodetest_pi;
  							nt_name = _lexer.contents();
  							_lexer.next();
  
  							if (_lexer.current() != lex_close_brace)
  								return error("Unmatched brace near processing-instruction()");
  							_lexer.next();
  						}
  						else
  						{
  							return error("Unmatched brace near node type test");
  						}
  					}
  					// QName or NCName:*
  					else
  					{
  						if (nt_name.end - nt_name.begin > 2 && nt_name.end[-2] == ':' && nt_name.end[-1] == '*') // NCName:*
  						{
  							nt_name.end--; // erase *
  
  							nt_type = nodetest_all_in_namespace;
  						}
  						else
  						{
  							nt_type = nodetest_name;
  						}
  					}
  				}
  			}
  			else if (_lexer.current() == lex_multiply)
  			{
  				nt_type = nodetest_all;
  				_lexer.next();
  			}
  			else
  			{
  				return error("Unrecognized node test");
  			}
  
  			const char_t* nt_name_copy = alloc_string(nt_name);
  			if (!nt_name_copy) return 0;
  
  			xpath_ast_node* n = alloc_node(ast_step, set, axis, nt_type, nt_name_copy);
  			if (!n) return 0;
  
  			xpath_ast_node* last = 0;
  
  			while (_lexer.current() == lex_open_square_brace)
  			{
  				_lexer.next();
  
  				xpath_ast_node* expr = parse_expression();
  				if (!expr) return 0;
  
  				xpath_ast_node* pred = alloc_node(ast_predicate, 0, expr, predicate_default);
  				if (!pred) return 0;
  
  				if (_lexer.current() != lex_close_square_brace)
  					return error("Expected ']' to match an opening '['");
  				_lexer.next();
  
  				if (last) last->set_next(pred);
  				else n->set_right(pred);
  
  				last = pred;
  			}
  
  			return n;
  		}
  
  		// RelativeLocationPath ::= Step | RelativeLocationPath '/' Step | RelativeLocationPath '//' Step
  		xpath_ast_node* parse_relative_location_path(xpath_ast_node* set)
  		{
  			xpath_ast_node* n = parse_step(set);
  			if (!n) return 0;
  
  			while (_lexer.current() == lex_slash || _lexer.current() == lex_double_slash)
  			{
  				lexeme_t l = _lexer.current();
  				_lexer.next();
  
  				if (l == lex_double_slash)
  				{
  					n = alloc_node(ast_step, n, axis_descendant_or_self, nodetest_type_node, 0);
  					if (!n) return 0;
  				}
  
  				n = parse_step(n);
  				if (!n) return 0;
  			}
  
  			return n;
  		}
  
  		// LocationPath ::= RelativeLocationPath | AbsoluteLocationPath
  		// AbsoluteLocationPath ::= '/' RelativeLocationPath? | '//' RelativeLocationPath
  		xpath_ast_node* parse_location_path()
  		{
  			if (_lexer.current() == lex_slash)
  			{
  				_lexer.next();
  
  				xpath_ast_node* n = alloc_node(ast_step_root, xpath_type_node_set);
  				if (!n) return 0;
  
  				// relative location path can start from axis_attribute, dot, double_dot, multiply and string lexemes; any other lexeme means standalone root path
  				lexeme_t l = _lexer.current();
  
  				if (l == lex_string || l == lex_axis_attribute || l == lex_dot || l == lex_double_dot || l == lex_multiply)
  					return parse_relative_location_path(n);
  				else
  					return n;
  			}
  			else if (_lexer.current() == lex_double_slash)
  			{
  				_lexer.next();
  
  				xpath_ast_node* n = alloc_node(ast_step_root, xpath_type_node_set);
  				if (!n) return 0;
  
  				n = alloc_node(ast_step, n, axis_descendant_or_self, nodetest_type_node, 0);
  				if (!n) return 0;
  
  				return parse_relative_location_path(n);
  			}
  
  			// else clause moved outside of if because of bogus warning 'control may reach end of non-void function being inlined' in gcc 4.0.1
  			return parse_relative_location_path(0);
  		}
  
  		// PathExpr ::= LocationPath
  		//				| FilterExpr
  		//				| FilterExpr '/' RelativeLocationPath
  		//				| FilterExpr '//' RelativeLocationPath
  		// UnionExpr ::= PathExpr | UnionExpr '|' PathExpr
  		// UnaryExpr ::= UnionExpr | '-' UnaryExpr
  		xpath_ast_node* parse_path_or_unary_expression()
  		{
  			// Clarification.
  			// PathExpr begins with either LocationPath or FilterExpr.
  			// FilterExpr begins with PrimaryExpr
  			// PrimaryExpr begins with '$' in case of it being a variable reference,
  			// '(' in case of it being an expression, string literal, number constant or
  			// function call.
  			if (_lexer.current() == lex_var_ref || _lexer.current() == lex_open_brace ||
  				_lexer.current() == lex_quoted_string || _lexer.current() == lex_number ||
  				_lexer.current() == lex_string)
  			{
  				if (_lexer.current() == lex_string)
  				{
  					// This is either a function call, or not - if not, we shall proceed with location path
  					const char_t* state = _lexer.state();
  
  					while (PUGI__IS_CHARTYPE(*state, ct_space)) ++state;
  
  					if (*state != '(')
  						return parse_location_path();
  
  					// This looks like a function call; however this still can be a node-test. Check it.
  					if (parse_node_test_type(_lexer.contents()) != nodetest_none)
  						return parse_location_path();
  				}
  
  				xpath_ast_node* n = parse_filter_expression();
  				if (!n) return 0;
  
  				if (_lexer.current() == lex_slash || _lexer.current() == lex_double_slash)
  				{
  					lexeme_t l = _lexer.current();
  					_lexer.next();
  
  					if (l == lex_double_slash)
  					{
  						if (n->rettype() != xpath_type_node_set)
  							return error("Step has to be applied to node set");
  
  						n = alloc_node(ast_step, n, axis_descendant_or_self, nodetest_type_node, 0);
  						if (!n) return 0;
  					}
  
  					// select from location path
  					return parse_relative_location_path(n);
  				}
  
  				return n;
  			}
  			else if (_lexer.current() == lex_minus)
  			{
  				_lexer.next();
  
  				// precedence 7+ - only parses union expressions
  				xpath_ast_node* n = parse_expression(7);
  				if (!n) return 0;
  
  				return alloc_node(ast_op_negate, xpath_type_number, n);
  			}
  			else
  			{
  				return parse_location_path();
  			}
  		}
  
  		struct binary_op_t
  		{
  			ast_type_t asttype;
  			xpath_value_type rettype;
  			int precedence;
  
  			binary_op_t(): asttype(ast_unknown), rettype(xpath_type_none), precedence(0)
  			{
  			}
  
  			binary_op_t(ast_type_t asttype_, xpath_value_type rettype_, int precedence_): asttype(asttype_), rettype(rettype_), precedence(precedence_)
  			{
  			}
  
  			static binary_op_t parse(xpath_lexer& lexer)
  			{
  				switch (lexer.current())
  				{
  				case lex_string:
  					if (lexer.contents() == PUGIXML_TEXT("or"))
  						return binary_op_t(ast_op_or, xpath_type_boolean, 1);
  					else if (lexer.contents() == PUGIXML_TEXT("and"))
  						return binary_op_t(ast_op_and, xpath_type_boolean, 2);
  					else if (lexer.contents() == PUGIXML_TEXT("div"))
  						return binary_op_t(ast_op_divide, xpath_type_number, 6);
  					else if (lexer.contents() == PUGIXML_TEXT("mod"))
  						return binary_op_t(ast_op_mod, xpath_type_number, 6);
  					else
  						return binary_op_t();
  
  				case lex_equal:
  					return binary_op_t(ast_op_equal, xpath_type_boolean, 3);
  
  				case lex_not_equal:
  					return binary_op_t(ast_op_not_equal, xpath_type_boolean, 3);
  
  				case lex_less:
  					return binary_op_t(ast_op_less, xpath_type_boolean, 4);
  
  				case lex_greater:
  					return binary_op_t(ast_op_greater, xpath_type_boolean, 4);
  
  				case lex_less_or_equal:
  					return binary_op_t(ast_op_less_or_equal, xpath_type_boolean, 4);
  
  				case lex_greater_or_equal:
  					return binary_op_t(ast_op_greater_or_equal, xpath_type_boolean, 4);
  
  				case lex_plus:
  					return binary_op_t(ast_op_add, xpath_type_number, 5);
  
  				case lex_minus:
  					return binary_op_t(ast_op_subtract, xpath_type_number, 5);
  
  				case lex_multiply:
  					return binary_op_t(ast_op_multiply, xpath_type_number, 6);
  
  				case lex_union:
  					return binary_op_t(ast_op_union, xpath_type_node_set, 7);
  
  				default:
  					return binary_op_t();
  				}
  			}
  		};
  
  		xpath_ast_node* parse_expression_rec(xpath_ast_node* lhs, int limit)
  		{
  			binary_op_t op = binary_op_t::parse(_lexer);
  
  			while (op.asttype != ast_unknown && op.precedence >= limit)
  			{
  				_lexer.next();
  
  				xpath_ast_node* rhs = parse_path_or_unary_expression();
  				if (!rhs) return 0;
  
  				binary_op_t nextop = binary_op_t::parse(_lexer);
  
  				while (nextop.asttype != ast_unknown && nextop.precedence > op.precedence)
  				{
  					rhs = parse_expression_rec(rhs, nextop.precedence);
  					if (!rhs) return 0;
  
  					nextop = binary_op_t::parse(_lexer);
  				}
  
  				if (op.asttype == ast_op_union && (lhs->rettype() != xpath_type_node_set || rhs->rettype() != xpath_type_node_set))
  					return error("Union operator has to be applied to node sets");
  
  				lhs = alloc_node(op.asttype, op.rettype, lhs, rhs);
  				if (!lhs) return 0;
  
  				op = binary_op_t::parse(_lexer);
  			}
  
  			return lhs;
  		}
  
  		// Expr ::= OrExpr
  		// OrExpr ::= AndExpr | OrExpr 'or' AndExpr
  		// AndExpr ::= EqualityExpr | AndExpr 'and' EqualityExpr
  		// EqualityExpr ::= RelationalExpr
  		//					| EqualityExpr '=' RelationalExpr
  		//					| EqualityExpr '!=' RelationalExpr
  		// RelationalExpr ::= AdditiveExpr
  		//					  | RelationalExpr '<' AdditiveExpr
  		//					  | RelationalExpr '>' AdditiveExpr
  		//					  | RelationalExpr '<=' AdditiveExpr
  		//					  | RelationalExpr '>=' AdditiveExpr
  		// AdditiveExpr ::= MultiplicativeExpr
  		//					| AdditiveExpr '+' MultiplicativeExpr
  		//					| AdditiveExpr '-' MultiplicativeExpr
  		// MultiplicativeExpr ::= UnaryExpr
  		//						  | MultiplicativeExpr '*' UnaryExpr
  		//						  | MultiplicativeExpr 'div' UnaryExpr
  		//						  | MultiplicativeExpr 'mod' UnaryExpr
  		xpath_ast_node* parse_expression(int limit = 0)
  		{
  			xpath_ast_node* n = parse_path_or_unary_expression();
  			if (!n) return 0;
  
  			return parse_expression_rec(n, limit);
  		}
  
  		xpath_parser(const char_t* query, xpath_variable_set* variables, xpath_allocator* alloc, xpath_parse_result* result): _alloc(alloc), _lexer(query), _query(query), _variables(variables), _result(result)
  		{
  		}
  
  		xpath_ast_node* parse()
  		{
  			xpath_ast_node* n = parse_expression();
  			if (!n) return 0;
  
  			// check if there are unparsed tokens left
  			if (_lexer.current() != lex_eof)
  				return error("Incorrect query");
  
  			return n;
  		}
  
  		static xpath_ast_node* parse(const char_t* query, xpath_variable_set* variables, xpath_allocator* alloc, xpath_parse_result* result)
  		{
  			xpath_parser parser(query, variables, alloc, result);
  
  			return parser.parse();
  		}
  	};
  
  	struct xpath_query_impl
  	{
  		static xpath_query_impl* create()
  		{
  			void* memory = xml_memory::allocate(sizeof(xpath_query_impl));
  			if (!memory) return 0;
  
  			return new (memory) xpath_query_impl();
  		}
  
  		static void destroy(xpath_query_impl* impl)
  		{
  			// free all allocated pages
  			impl->alloc.release();
  
  			// free allocator memory (with the first page)
  			xml_memory::deallocate(impl);
  		}
  
  		xpath_query_impl(): root(0), alloc(&block, &oom), oom(false)
  		{
  			block.next = 0;
  			block.capacity = sizeof(block.data);
  		}
  
  		xpath_ast_node* root;
  		xpath_allocator alloc;
  		xpath_memory_block block;
  		bool oom;
  	};
  
  	PUGI__FN impl::xpath_ast_node* evaluate_node_set_prepare(xpath_query_impl* impl)
  	{
  		if (!impl) return 0;
  
  		if (impl->root->rettype() != xpath_type_node_set)
  		{
  		#ifdef PUGIXML_NO_EXCEPTIONS
  			return 0;
  		#else
  			xpath_parse_result res;
  			res.error = "Expression does not evaluate to node set";
  
  			throw xpath_exception(res);
  		#endif
  		}
  
  		return impl->root;
  	}
  PUGI__NS_END
  
  namespace pugi
  {
  #ifndef PUGIXML_NO_EXCEPTIONS
  	PUGI__FN xpath_exception::xpath_exception(const xpath_parse_result& result_): _result(result_)
  	{
  		assert(_result.error);
  	}
  
  	PUGI__FN const char* xpath_exception::what() const throw()
  	{
  		return _result.error;
  	}
  
  	PUGI__FN const xpath_parse_result& xpath_exception::result() const
  	{
  		return _result;
  	}
  #endif
  
  	PUGI__FN xpath_node::xpath_node()
  	{
  	}
  
  	PUGI__FN xpath_node::xpath_node(const xml_node& node_): _node(node_)
  	{
  	}
  
  	PUGI__FN xpath_node::xpath_node(const xml_attribute& attribute_, const xml_node& parent_): _node(attribute_ ? parent_ : xml_node()), _attribute(attribute_)
  	{
  	}
  
  	PUGI__FN xml_node xpath_node::node() const
  	{
  		return _attribute ? xml_node() : _node;
  	}
  
  	PUGI__FN xml_attribute xpath_node::attribute() const
  	{
  		return _attribute;
  	}
  
  	PUGI__FN xml_node xpath_node::parent() const
  	{
  		return _attribute ? _node : _node.parent();
  	}
  
  	PUGI__FN static void unspecified_bool_xpath_node(xpath_node***)
  	{
  	}
  
  	PUGI__FN xpath_node::operator xpath_node::unspecified_bool_type() const
  	{
  		return (_node || _attribute) ? unspecified_bool_xpath_node : 0;
  	}
  
  	PUGI__FN bool xpath_node::operator!() const
  	{
  		return !(_node || _attribute);
  	}
  
  	PUGI__FN bool xpath_node::operator==(const xpath_node& n) const
  	{
  		return _node == n._node && _attribute == n._attribute;
  	}
  
  	PUGI__FN bool xpath_node::operator!=(const xpath_node& n) const
  	{
  		return _node != n._node || _attribute != n._attribute;
  	}
  
  #ifdef __BORLANDC__
  	PUGI__FN bool operator&&(const xpath_node& lhs, bool rhs)
  	{
  		return (bool)lhs && rhs;
  	}
  
  	PUGI__FN bool operator||(const xpath_node& lhs, bool rhs)
  	{
  		return (bool)lhs || rhs;
  	}
  #endif
  
  	PUGI__FN void xpath_node_set::_assign(const_iterator begin_, const_iterator end_, type_t type_)
  	{
  		assert(begin_ <= end_);
  
  		size_t size_ = static_cast<size_t>(end_ - begin_);
  
  		if (size_ <= 1)
  		{
  			// deallocate old buffer
  			if (_begin != &_storage) impl::xml_memory::deallocate(_begin);
  
  			// use internal buffer
  			if (begin_ != end_) _storage = *begin_;
  
  			_begin = &_storage;
  			_end = &_storage + size_;
  			_type = type_;
  		}
  		else
  		{
  			// make heap copy
  			xpath_node* storage = static_cast<xpath_node*>(impl::xml_memory::allocate(size_ * sizeof(xpath_node)));
  
  			if (!storage)
  			{
  			#ifdef PUGIXML_NO_EXCEPTIONS
  				return;
  			#else
  				throw std::bad_alloc();
  			#endif
  			}
  
  			memcpy(storage, begin_, size_ * sizeof(xpath_node));
  
  			// deallocate old buffer
  			if (_begin != &_storage) impl::xml_memory::deallocate(_begin);
  
  			// finalize
  			_begin = storage;
  			_end = storage + size_;
  			_type = type_;
  		}
  	}
  
  #ifdef PUGIXML_HAS_MOVE
  	PUGI__FN void xpath_node_set::_move(xpath_node_set& rhs)
  	{
  		_type = rhs._type;
  		_storage = rhs._storage;
  		_begin = (rhs._begin == &rhs._storage) ? &_storage : rhs._begin;
  		_end = _begin + (rhs._end - rhs._begin);
  
  		rhs._type = type_unsorted;
  		rhs._begin = &rhs._storage;
  		rhs._end = rhs._begin;
  	}
  #endif
  
  	PUGI__FN xpath_node_set::xpath_node_set(): _type(type_unsorted), _begin(&_storage), _end(&_storage)
  	{
  	}
  
  	PUGI__FN xpath_node_set::xpath_node_set(const_iterator begin_, const_iterator end_, type_t type_): _type(type_unsorted), _begin(&_storage), _end(&_storage)
  	{
  		_assign(begin_, end_, type_);
  	}
  
  	PUGI__FN xpath_node_set::~xpath_node_set()
  	{
  		if (_begin != &_storage)
  			impl::xml_memory::deallocate(_begin);
  	}
  
  	PUGI__FN xpath_node_set::xpath_node_set(const xpath_node_set& ns): _type(type_unsorted), _begin(&_storage), _end(&_storage)
  	{
  		_assign(ns._begin, ns._end, ns._type);
  	}
  
  	PUGI__FN xpath_node_set& xpath_node_set::operator=(const xpath_node_set& ns)
  	{
  		if (this == &ns) return *this;
  
  		_assign(ns._begin, ns._end, ns._type);
  
  		return *this;
  	}
  
  #ifdef PUGIXML_HAS_MOVE
  	PUGI__FN xpath_node_set::xpath_node_set(xpath_node_set&& rhs): _type(type_unsorted), _begin(&_storage), _end(&_storage)
  	{
  		_move(rhs);
  	}
  
  	PUGI__FN xpath_node_set& xpath_node_set::operator=(xpath_node_set&& rhs)
  	{
  		if (this == &rhs) return *this;
  
  		if (_begin != &_storage)
  			impl::xml_memory::deallocate(_begin);
  
  		_move(rhs);
  
  		return *this;
  	}
  #endif
  
  	PUGI__FN xpath_node_set::type_t xpath_node_set::type() const
  	{
  		return _type;
  	}
  
  	PUGI__FN size_t xpath_node_set::size() const
  	{
  		return _end - _begin;
  	}
  
  	PUGI__FN bool xpath_node_set::empty() const
  	{
  		return _begin == _end;
  	}
  
  	PUGI__FN const xpath_node& xpath_node_set::operator[](size_t index) const
  	{
  		assert(index < size());
  		return _begin[index];
  	}
  
  	PUGI__FN xpath_node_set::const_iterator xpath_node_set::begin() const
  	{
  		return _begin;
  	}
  
  	PUGI__FN xpath_node_set::const_iterator xpath_node_set::end() const
  	{
  		return _end;
  	}
  
  	PUGI__FN void xpath_node_set::sort(bool reverse)
  	{
  		_type = impl::xpath_sort(_begin, _end, _type, reverse);
  	}
  
  	PUGI__FN xpath_node xpath_node_set::first() const
  	{
  		return impl::xpath_first(_begin, _end, _type);
  	}
  
  	PUGI__FN xpath_parse_result::xpath_parse_result(): error("Internal error"), offset(0)
  	{
  	}
  
  	PUGI__FN xpath_parse_result::operator bool() const
  	{
  		return error == 0;
  	}
  
  	PUGI__FN const char* xpath_parse_result::description() const
  	{
  		return error ? error : "No error";
  	}
  
  	PUGI__FN xpath_variable::xpath_variable(xpath_value_type type_): _type(type_), _next(0)
  	{
  	}
  
  	PUGI__FN const char_t* xpath_variable::name() const
  	{
  		switch (_type)
  		{
  		case xpath_type_node_set:
  			return static_cast<const impl::xpath_variable_node_set*>(this)->name;
  
  		case xpath_type_number:
  			return static_cast<const impl::xpath_variable_number*>(this)->name;
  
  		case xpath_type_string:
  			return static_cast<const impl::xpath_variable_string*>(this)->name;
  
  		case xpath_type_boolean:
  			return static_cast<const impl::xpath_variable_boolean*>(this)->name;
  
  		default:
  			assert(false && "Invalid variable type"); // unreachable
  			return 0;
  		}
  	}
  
  	PUGI__FN xpath_value_type xpath_variable::type() const
  	{
  		return _type;
  	}
  
  	PUGI__FN bool xpath_variable::get_boolean() const
  	{
  		return (_type == xpath_type_boolean) ? static_cast<const impl::xpath_variable_boolean*>(this)->value : false;
  	}
  
  	PUGI__FN double xpath_variable::get_number() const
  	{
  		return (_type == xpath_type_number) ? static_cast<const impl::xpath_variable_number*>(this)->value : impl::gen_nan();
  	}
  
  	PUGI__FN const char_t* xpath_variable::get_string() const
  	{
  		const char_t* value = (_type == xpath_type_string) ? static_cast<const impl::xpath_variable_string*>(this)->value : 0;
  		return value ? value : PUGIXML_TEXT("");
  	}
  
  	PUGI__FN const xpath_node_set& xpath_variable::get_node_set() const
  	{
  		return (_type == xpath_type_node_set) ? static_cast<const impl::xpath_variable_node_set*>(this)->value : impl::dummy_node_set;
  	}
  
  	PUGI__FN bool xpath_variable::set(bool value)
  	{
  		if (_type != xpath_type_boolean) return false;
  
  		static_cast<impl::xpath_variable_boolean*>(this)->value = value;
  		return true;
  	}
  
  	PUGI__FN bool xpath_variable::set(double value)
  	{
  		if (_type != xpath_type_number) return false;
  
  		static_cast<impl::xpath_variable_number*>(this)->value = value;
  		return true;
  	}
  
  	PUGI__FN bool xpath_variable::set(const char_t* value)
  	{
  		if (_type != xpath_type_string) return false;
  
  		impl::xpath_variable_string* var = static_cast<impl::xpath_variable_string*>(this);
  
  		// duplicate string
  		size_t size = (impl::strlength(value) + 1) * sizeof(char_t);
  
  		char_t* copy = static_cast<char_t*>(impl::xml_memory::allocate(size));
  		if (!copy) return false;
  
  		memcpy(copy, value, size);
  
  		// replace old string
  		if (var->value) impl::xml_memory::deallocate(var->value);
  		var->value = copy;
  
  		return true;
  	}
  
  	PUGI__FN bool xpath_variable::set(const xpath_node_set& value)
  	{
  		if (_type != xpath_type_node_set) return false;
  
  		static_cast<impl::xpath_variable_node_set*>(this)->value = value;
  		return true;
  	}
  
  	PUGI__FN xpath_variable_set::xpath_variable_set()
  	{
  		for (size_t i = 0; i < sizeof(_data) / sizeof(_data[0]); ++i)
  			_data[i] = 0;
  	}
  
  	PUGI__FN xpath_variable_set::~xpath_variable_set()
  	{
  		for (size_t i = 0; i < sizeof(_data) / sizeof(_data[0]); ++i)
  			_destroy(_data[i]);
  	}
  
  	PUGI__FN xpath_variable_set::xpath_variable_set(const xpath_variable_set& rhs)
  	{
  		for (size_t i = 0; i < sizeof(_data) / sizeof(_data[0]); ++i)
  			_data[i] = 0;
  
  		_assign(rhs);
  	}
  
  	PUGI__FN xpath_variable_set& xpath_variable_set::operator=(const xpath_variable_set& rhs)
  	{
  		if (this == &rhs) return *this;
  
  		_assign(rhs);
  
  		return *this;
  	}
  
  #ifdef PUGIXML_HAS_MOVE
  	PUGI__FN xpath_variable_set::xpath_variable_set(xpath_variable_set&& rhs)
  	{
  		for (size_t i = 0; i < sizeof(_data) / sizeof(_data[0]); ++i)
  		{
  			_data[i] = rhs._data[i];
  			rhs._data[i] = 0;
  		}
  	}
  
  	PUGI__FN xpath_variable_set& xpath_variable_set::operator=(xpath_variable_set&& rhs)
  	{
  		for (size_t i = 0; i < sizeof(_data) / sizeof(_data[0]); ++i)
  		{
  			_destroy(_data[i]);
  
  			_data[i] = rhs._data[i];
  			rhs._data[i] = 0;
  		}
  
  		return *this;
  	}
  #endif
  
  	PUGI__FN void xpath_variable_set::_assign(const xpath_variable_set& rhs)
  	{
  		xpath_variable_set temp;
  
  		for (size_t i = 0; i < sizeof(_data) / sizeof(_data[0]); ++i)
  			if (rhs._data[i] && !_clone(rhs._data[i], &temp._data[i]))
  				return;
  
  		_swap(temp);
  	}
  
  	PUGI__FN void xpath_variable_set::_swap(xpath_variable_set& rhs)
  	{
  		for (size_t i = 0; i < sizeof(_data) / sizeof(_data[0]); ++i)
  		{
  			xpath_variable* chain = _data[i];
  
  			_data[i] = rhs._data[i];
  			rhs._data[i] = chain;
  		}
  	}
  
  	PUGI__FN xpath_variable* xpath_variable_set::_find(const char_t* name) const
  	{
  		const size_t hash_size = sizeof(_data) / sizeof(_data[0]);
  		size_t hash = impl::hash_string(name) % hash_size;
  
  		// look for existing variable
  		for (xpath_variable* var = _data[hash]; var; var = var->_next)
  			if (impl::strequal(var->name(), name))
  				return var;
  
  		return 0;
  	}
  
  	PUGI__FN bool xpath_variable_set::_clone(xpath_variable* var, xpath_variable** out_result)
  	{
  		xpath_variable* last = 0;
  
  		while (var)
  		{
  			// allocate storage for new variable
  			xpath_variable* nvar = impl::new_xpath_variable(var->_type, var->name());
  			if (!nvar) return false;
  
  			// link the variable to the result immediately to handle failures gracefully
  			if (last)
  				last->_next = nvar;
  			else
  				*out_result = nvar;
  
  			last = nvar;
  
  			// copy the value; this can fail due to out-of-memory conditions
  			if (!impl::copy_xpath_variable(nvar, var)) return false;
  
  			var = var->_next;
  		}
  
  		return true;
  	}
  
  	PUGI__FN void xpath_variable_set::_destroy(xpath_variable* var)
  	{
  		while (var)
  		{
  			xpath_variable* next = var->_next;
  
  			impl::delete_xpath_variable(var->_type, var);
  
  			var = next;
  		}
  	}
  
  	PUGI__FN xpath_variable* xpath_variable_set::add(const char_t* name, xpath_value_type type)
  	{
  		const size_t hash_size = sizeof(_data) / sizeof(_data[0]);
  		size_t hash = impl::hash_string(name) % hash_size;
  
  		// look for existing variable
  		for (xpath_variable* var = _data[hash]; var; var = var->_next)
  			if (impl::strequal(var->name(), name))
  				return var->type() == type ? var : 0;
  
  		// add new variable
  		xpath_variable* result = impl::new_xpath_variable(type, name);
  
  		if (result)
  		{
  			result->_next = _data[hash];
  
  			_data[hash] = result;
  		}
  
  		return result;
  	}
  
  	PUGI__FN bool xpath_variable_set::set(const char_t* name, bool value)
  	{
  		xpath_variable* var = add(name, xpath_type_boolean);
  		return var ? var->set(value) : false;
  	}
  
  	PUGI__FN bool xpath_variable_set::set(const char_t* name, double value)
  	{
  		xpath_variable* var = add(name, xpath_type_number);
  		return var ? var->set(value) : false;
  	}
  
  	PUGI__FN bool xpath_variable_set::set(const char_t* name, const char_t* value)
  	{
  		xpath_variable* var = add(name, xpath_type_string);
  		return var ? var->set(value) : false;
  	}
  
  	PUGI__FN bool xpath_variable_set::set(const char_t* name, const xpath_node_set& value)
  	{
  		xpath_variable* var = add(name, xpath_type_node_set);
  		return var ? var->set(value) : false;
  	}
  
  	PUGI__FN xpath_variable* xpath_variable_set::get(const char_t* name)
  	{
  		return _find(name);
  	}
  
  	PUGI__FN const xpath_variable* xpath_variable_set::get(const char_t* name) const
  	{
  		return _find(name);
  	}
  
  	PUGI__FN xpath_query::xpath_query(const char_t* query, xpath_variable_set* variables): _impl(0)
  	{
  		impl::xpath_query_impl* qimpl = impl::xpath_query_impl::create();
  
  		if (!qimpl)
  		{
  		#ifdef PUGIXML_NO_EXCEPTIONS
  			_result.error = "Out of memory";
  		#else
  			throw std::bad_alloc();
  		#endif
  		}
  		else
  		{
  			using impl::auto_deleter; // MSVC7 workaround
  			auto_deleter<impl::xpath_query_impl> impl(qimpl, impl::xpath_query_impl::destroy);
  
  			qimpl->root = impl::xpath_parser::parse(query, variables, &qimpl->alloc, &_result);
  
  			if (qimpl->root)
  			{
  				qimpl->root->optimize(&qimpl->alloc);
  
  				_impl = impl.release();
  				_result.error = 0;
  			}
  			else
  			{
  			#ifdef PUGIXML_NO_EXCEPTIONS
  				if (qimpl->oom) _result.error = "Out of memory";
  			#else
  				if (qimpl->oom) throw std::bad_alloc();
  				throw xpath_exception(_result);
  			#endif
  			}
  		}
  	}
  
  	PUGI__FN xpath_query::xpath_query(): _impl(0)
  	{
  	}
  
  	PUGI__FN xpath_query::~xpath_query()
  	{
  		if (_impl)
  			impl::xpath_query_impl::destroy(static_cast<impl::xpath_query_impl*>(_impl));
  	}
  
  #ifdef PUGIXML_HAS_MOVE
  	PUGI__FN xpath_query::xpath_query(xpath_query&& rhs)
  	{
  		_impl = rhs._impl;
  		_result = rhs._result;
  		rhs._impl = 0;
  		rhs._result = xpath_parse_result();
  	}
  
  	PUGI__FN xpath_query& xpath_query::operator=(xpath_query&& rhs)
  	{
  		if (this == &rhs) return *this;
  
  		if (_impl)
  			impl::xpath_query_impl::destroy(static_cast<impl::xpath_query_impl*>(_impl));
  
  		_impl = rhs._impl;
  		_result = rhs._result;
  		rhs._impl = 0;
  		rhs._result = xpath_parse_result();
  
  		return *this;
  	}
  #endif
  
  	PUGI__FN xpath_value_type xpath_query::return_type() const
  	{
  		if (!_impl) return xpath_type_none;
  
  		return static_cast<impl::xpath_query_impl*>(_impl)->root->rettype();
  	}
  
  	PUGI__FN bool xpath_query::evaluate_boolean(const xpath_node& n) const
  	{
  		if (!_impl) return false;
  
  		impl::xpath_context c(n, 1, 1);
  		impl::xpath_stack_data sd;
  
  		bool r = static_cast<impl::xpath_query_impl*>(_impl)->root->eval_boolean(c, sd.stack);
  
  		if (sd.oom)
  		{
  		#ifdef PUGIXML_NO_EXCEPTIONS
  			return false;
  		#else
  			throw std::bad_alloc();
  		#endif
  		}
  
  		return r;
  	}
  
  	PUGI__FN double xpath_query::evaluate_number(const xpath_node& n) const
  	{
  		if (!_impl) return impl::gen_nan();
  
  		impl::xpath_context c(n, 1, 1);
  		impl::xpath_stack_data sd;
  
  		double r = static_cast<impl::xpath_query_impl*>(_impl)->root->eval_number(c, sd.stack);
  
  		if (sd.oom)
  		{
  		#ifdef PUGIXML_NO_EXCEPTIONS
  			return impl::gen_nan();
  		#else
  			throw std::bad_alloc();
  		#endif
  		}
  
  		return r;
  	}
  
  #ifndef PUGIXML_NO_STL
  	PUGI__FN string_t xpath_query::evaluate_string(const xpath_node& n) const
  	{
  		if (!_impl) return string_t();
  
  		impl::xpath_context c(n, 1, 1);
  		impl::xpath_stack_data sd;
  
  		impl::xpath_string r = static_cast<impl::xpath_query_impl*>(_impl)->root->eval_string(c, sd.stack);
  
  		if (sd.oom)
  		{
  		#ifdef PUGIXML_NO_EXCEPTIONS
  			return string_t();
  		#else
  			throw std::bad_alloc();
  		#endif
  		}
  
  		return string_t(r.c_str(), r.length());
  	}
  #endif
  
  	PUGI__FN size_t xpath_query::evaluate_string(char_t* buffer, size_t capacity, const xpath_node& n) const
  	{
  		impl::xpath_context c(n, 1, 1);
  		impl::xpath_stack_data sd;
  
  		impl::xpath_string r = _impl ? static_cast<impl::xpath_query_impl*>(_impl)->root->eval_string(c, sd.stack) : impl::xpath_string();
  
  		if (sd.oom)
  		{
  		#ifdef PUGIXML_NO_EXCEPTIONS
  			r = impl::xpath_string();
  		#else
  			throw std::bad_alloc();
  		#endif
  		}
  
  		size_t full_size = r.length() + 1;
  
  		if (capacity > 0)
  		{
  			size_t size = (full_size < capacity) ? full_size : capacity;
  			assert(size > 0);
  
  			memcpy(buffer, r.c_str(), (size - 1) * sizeof(char_t));
  			buffer[size - 1] = 0;
  		}
  
  		return full_size;
  	}
  
  	PUGI__FN xpath_node_set xpath_query::evaluate_node_set(const xpath_node& n) const
  	{
  		impl::xpath_ast_node* root = impl::evaluate_node_set_prepare(static_cast<impl::xpath_query_impl*>(_impl));
  		if (!root) return xpath_node_set();
  
  		impl::xpath_context c(n, 1, 1);
  		impl::xpath_stack_data sd;
  
  		impl::xpath_node_set_raw r = root->eval_node_set(c, sd.stack, impl::nodeset_eval_all);
  
  		if (sd.oom)
  		{
  		#ifdef PUGIXML_NO_EXCEPTIONS
  			return xpath_node_set();
  		#else
  			throw std::bad_alloc();
  		#endif
  		}
  
  		return xpath_node_set(r.begin(), r.end(), r.type());
  	}
  
  	PUGI__FN xpath_node xpath_query::evaluate_node(const xpath_node& n) const
  	{
  		impl::xpath_ast_node* root = impl::evaluate_node_set_prepare(static_cast<impl::xpath_query_impl*>(_impl));
  		if (!root) return xpath_node();
  
  		impl::xpath_context c(n, 1, 1);
  		impl::xpath_stack_data sd;
  
  		impl::xpath_node_set_raw r = root->eval_node_set(c, sd.stack, impl::nodeset_eval_first);
  
  		if (sd.oom)
  		{
  		#ifdef PUGIXML_NO_EXCEPTIONS
  			return xpath_node();
  		#else
  			throw std::bad_alloc();
  		#endif
  		}
  
  		return r.first();
  	}
  
  	PUGI__FN const xpath_parse_result& xpath_query::result() const
  	{
  		return _result;
  	}
  
  	PUGI__FN static void unspecified_bool_xpath_query(xpath_query***)
  	{
  	}
  
  	PUGI__FN xpath_query::operator xpath_query::unspecified_bool_type() const
  	{
  		return _impl ? unspecified_bool_xpath_query : 0;
  	}
  
  	PUGI__FN bool xpath_query::operator!() const
  	{
  		return !_impl;
  	}
  
  	PUGI__FN xpath_node xml_node::select_node(const char_t* query, xpath_variable_set* variables) const
  	{
  		xpath_query q(query, variables);
  		return q.evaluate_node(*this);
  	}
  
  	PUGI__FN xpath_node xml_node::select_node(const xpath_query& query) const
  	{
  		return query.evaluate_node(*this);
  	}
  
  	PUGI__FN xpath_node_set xml_node::select_nodes(const char_t* query, xpath_variable_set* variables) const
  	{
  		xpath_query q(query, variables);
  		return q.evaluate_node_set(*this);
  	}
  
  	PUGI__FN xpath_node_set xml_node::select_nodes(const xpath_query& query) const
  	{
  		return query.evaluate_node_set(*this);
  	}
  
  	PUGI__FN xpath_node xml_node::select_single_node(const char_t* query, xpath_variable_set* variables) const
  	{
  		xpath_query q(query, variables);
  		return q.evaluate_node(*this);
  	}
  
  	PUGI__FN xpath_node xml_node::select_single_node(const xpath_query& query) const
  	{
  		return query.evaluate_node(*this);
  	}
  }
  
  #endif
  
  #ifdef __BORLANDC__
  #	pragma option pop
  #endif
  
  // Intel C++ does not properly keep warning state for function templates,
  // so popping warning state at the end of translation unit leads to warnings in the middle.
  #if defined(_MSC_VER) && !defined(__INTEL_COMPILER)
  #	pragma warning(pop)
  #endif
  
  #if defined(_MSC_VER) && defined(__c2__)
  #	pragma clang diagnostic pop
  #endif
  
  // Undefine all local macros (makes sure we're not leaking macros in header-only mode)
  #undef PUGI__NO_INLINE
  #undef PUGI__UNLIKELY
  #undef PUGI__STATIC_ASSERT
  #undef PUGI__DMC_VOLATILE
  #undef PUGI__UNSIGNED_OVERFLOW
  #undef PUGI__MSVC_CRT_VERSION
  #undef PUGI__SNPRINTF
  #undef PUGI__NS_BEGIN
  #undef PUGI__NS_END
  #undef PUGI__FN
  #undef PUGI__FN_NO_INLINE
  #undef PUGI__GETHEADER_IMPL
  #undef PUGI__GETPAGE_IMPL
  #undef PUGI__GETPAGE
  #undef PUGI__NODETYPE
  #undef PUGI__IS_CHARTYPE_IMPL
  #undef PUGI__IS_CHARTYPE
  #undef PUGI__IS_CHARTYPEX
  #undef PUGI__ENDSWITH
  #undef PUGI__SKIPWS
  #undef PUGI__OPTSET
  #undef PUGI__PUSHNODE
  #undef PUGI__POPNODE
  #undef PUGI__SCANFOR
  #undef PUGI__SCANWHILE
  #undef PUGI__SCANWHILE_UNROLL
  #undef PUGI__ENDSEG
  #undef PUGI__THROW_ERROR
  #undef PUGI__CHECK_ERROR
  
  #endif
  
  /**
   * Copyright (c) 2006-2018 Arseny Kapoulkine
   *
   * Permission is hereby granted, free of charge, to any person
   * obtaining a copy of this software and associated documentation
   * files (the "Software"), to deal in the Software without
   * restriction, including without limitation the rights to use,
   * copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the
   * Software is furnished to do so, subject to the following
   * conditions:
   *
   * The above copyright notice and this permission notice shall be
   * included in all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
   * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
   * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
   * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
   * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
   * OTHER DEALINGS IN THE SOFTWARE.
   */
  