text: /*
     � Copyright (c) Marshall Clow 2012-2015.
     � Copyright Beman Dawes 2015
  
     Distributed under the Boost Software License, Version 1.0. (See accompanying
     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  
      For more information, see http://www.boost.org
  
      Based on the StringRef implementation in LLVM (http://llvm.org) and
      N3422 by Jeffrey Yasskin
          http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3442.html
      Updated July 2015 to reflect the Library Fundamentals TS
          http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4480.html
  */
  
  #ifndef STX_STRING_VIEW_HPP_INCLUDED
  #define STX_STRING_VIEW_HPP_INCLUDED
  
  #ifndef STX_NAMESPACE_NAME
  #define STX_NAMESPACE_NAME stx
  #endif
  
  // libstdc++'s std::experimental::string_view requries C++14
  #if !defined(STX_NO_STD_STRING_VIEW) && (__cplusplus < 201402)
  #include <cstddef>
  #if defined(__GLIBCXX__)
  #define STX_NO_STD_STRING_VIEW
  #endif
  #endif
  
  #if defined(__has_include) && !defined(STX_NO_STD_STRING_VIEW)
  #if __has_include(<string_view>) && (__cplusplus > 201402)
          #include <string_view>
          #define STX_HAVE_STD_STRING_VIEW 1
          namespace STX_NAMESPACE_NAME {
              using std::basic_string_view;
              using std::string_view;
              using std::u16string_view;
              using std::u32string_view;
              using std::wstring_view;
          }
      #elif __has_include(<experimental/string_view>)
          #include <experimental/string_view>
          #define STX_HAVE_STD_STRING_VIEW 1
          namespace STX_NAMESPACE_NAME {
              using std::experimental::basic_string_view;
              using std::experimental::string_view;
              using std::experimental::u16string_view;
              using std::experimental::u32string_view;
              using std::experimental::wstring_view;
          }
      #endif // (__has_include(<string_view>) || __has_include(<experimental/string_view>))
  #endif // __has_include
  
  #ifndef STX_HAVE_STD_STRING_VIEW
  
  #include <cstddef>
  #include <stdexcept>
  #include <algorithm>
  #include <iterator>
  #include <string>
  #include <cstring>
  #include <iosfwd>
  
  #if __cpp_constexpr >= 201304
  #define STX_CONSTEXPR14 constexpr
  #else
  #define STX_CONSTEXPR14
  #endif
  
  namespace STX_NAMESPACE_NAME {
  
  namespace detail {
  //  A helper functor because sometimes we don't have lambdas
  template <typename charT, typename traits>
  class string_view_traits_eq {
  public:
      string_view_traits_eq ( charT ch ) : ch_(ch) {}
      bool operator()( charT val ) const { return traits::eq (ch_, val); }
      charT ch_;
  };
  }
  
  template<typename charT, typename traits = std::char_traits<charT>>
  class basic_string_view {
  public:
      // types
      typedef traits                                traits_type;
      typedef charT                                 value_type;
      typedef charT*                                pointer;
      typedef const charT*                          const_pointer;
      typedef charT&                                reference;
      typedef const charT&                          const_reference;
      typedef const_pointer                         const_iterator; // impl-defined
      typedef const_iterator                        iterator;
      typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
      typedef const_reverse_iterator                reverse_iterator;
      typedef std::size_t                           size_type;
      typedef std::ptrdiff_t                        difference_type;
      static constexpr size_type     npos = size_type(-1);
  
      // construct/copy
      constexpr basic_string_view() noexcept
              : ptr_(NULL), len_(0) {}
  
      // by defaulting these functions, basic_string_ref becomes
      //  trivially copy/move constructible.
      constexpr basic_string_view(const basic_string_view &rhs) noexcept = default;
  #if 0
      : ptr_(rhs.ptr_), len_(rhs.len_) {}
  #endif
  
      basic_string_view& operator=(const basic_string_view &rhs) noexcept
      = default;
  #if 0
      {
          ptr_ = rhs.ptr_;
          len_ = rhs.len_;
          return *this;
          }
  #endif
  
      template<typename Allocator>
      basic_string_view(const std::basic_string<charT, traits,
              Allocator>& str) noexcept
              : ptr_(str.data()), len_(str.length()) {}
  
      constexpr basic_string_view(const charT* str)
              : ptr_(str), len_(traits::length(str)) {}
  
      constexpr basic_string_view(const charT* str, size_type len)
              : ptr_(str), len_(len) {}
  
      // iterators
      constexpr const_iterator   begin() const noexcept { return ptr_; }
      constexpr const_iterator  cbegin() const noexcept { return ptr_; }
      constexpr const_iterator     end() const noexcept { return ptr_ + len_; }
      constexpr const_iterator    cend() const noexcept { return ptr_ + len_; }
      const_reverse_iterator  rbegin() const noexcept { return const_reverse_iterator(end()); }
      const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator(end()); }
      const_reverse_iterator    rend() const noexcept { return const_reverse_iterator(begin()); }
      const_reverse_iterator   crend() const noexcept { return const_reverse_iterator(begin()); }
  
      // capacity
      constexpr size_type size()     const noexcept { return len_; }
      constexpr size_type length()   const noexcept { return len_; }
      constexpr size_type max_size() const noexcept { return len_; }
      constexpr bool empty()         const noexcept { return len_ == 0; }
  
      // element access
      constexpr const_reference operator[](size_type pos) const noexcept { return ptr_[pos]; }
  
      constexpr const_reference at(size_t pos) const {
          return pos >= len_ ?  throw std::out_of_range("stx::string_view::at") : ptr_[pos];
  //             if ( pos >= len_ )
  //                 BOOST_THROW_EXCEPTION( std::out_of_range ( "stx::string_view::at" ) );
  //             return ptr_[pos];
      }
  
      constexpr const_reference front() const                { return ptr_[0]; }
      constexpr const_reference back()  const                { return ptr_[len_-1]; }
      constexpr const_pointer data()    const noexcept { return ptr_; }
  
      // modifiers
      void clear() noexcept { len_ = 0; }          // Boost extension
  
      STX_CONSTEXPR14 void remove_prefix(size_type n) {
          if ( n > len_ )
              n = len_;
          ptr_ += n;
          len_ -= n;
      }
  
      STX_CONSTEXPR14 void remove_suffix(size_type n) {
          if ( n > len_ )
              n = len_;
          len_ -= n;
      }
  
      STX_CONSTEXPR14 void swap(basic_string_view& s) noexcept {
          std::swap(ptr_, s.ptr_);
          std::swap(len_, s.len_);
      }
  
      // basic_string_view string operations
  #ifndef BOOST_NO_CXX11_EXPLICIT_CONVERSION_OPERATORS
      template<typename Allocator>
      explicit operator std::basic_string<charT, traits, Allocator>() const {
          return std::basic_string<charT, traits, Allocator>(begin(), end());
      }
  #endif
  
  #ifndef BOOST_NO_CXX11_FUNCTION_TEMPLATE_DEFAULT_ARGS
      template<typename Allocator = std::allocator<charT> >
      std::basic_string<charT, traits, Allocator> to_string(const Allocator& a = Allocator()) const {
          return std::basic_string<charT, traits, Allocator>(begin(), end(), a);
      }
  #else
      std::basic_string<charT, traits> to_string() const {
              return std::basic_string<charT, traits>(begin(), end());
              }
  
          template<typename Allocator>
          std::basic_string<charT, traits, Allocator> to_string(const Allocator& a) const {
              return std::basic_string<charT, traits, Allocator>(begin(), end(), a);
              }
  #endif
  
      size_type copy(charT* s, size_type n, size_type pos=0) const {
          if (pos > size())
              throw std::out_of_range("string_view::copy" );
          size_type rlen = (std::min)(n, len_ - pos);
          // use std::copy(begin() + pos, begin() + pos + rlen, s) rather than
          // std::copy_n(begin() + pos, rlen, s) to support pre-C++11 standard libraries
          std::copy(begin() + pos, begin() + pos + rlen, s);
          return rlen;
      }
  
      STX_CONSTEXPR14 basic_string_view substr(size_type pos, size_type n=npos) const {
          if ( pos > size())
              throw std::out_of_range ( "string_view::substr" );
          if (n == npos || pos + n > size())
              n = size () - pos;
          return basic_string_view(data() + pos, n);
      }
  
      STX_CONSTEXPR14 int compare(basic_string_view x) const noexcept {
          const int cmp = traits::compare(ptr_, x.ptr_, (std::min)(len_, x.len_));
          return cmp != 0 ? cmp : (len_ == x.len_ ? 0 : len_ < x.len_ ? -1 : 1);
      }
  
      STX_CONSTEXPR14 int compare(size_type pos1, size_type n1, basic_string_view x)
      const noexcept {
          return substr(pos1, n1).compare(x);
      }
  
      STX_CONSTEXPR14 int compare(size_type pos1, size_type n1,
                                        basic_string_view x, size_type pos2, size_type n2) const {
          return substr(pos1, n1).compare(x.substr(pos2, n2));
      }
  
      STX_CONSTEXPR14 int compare(const charT* x) const {
          return compare(basic_string_view(x));
      }
  
      STX_CONSTEXPR14 int compare(size_type pos1, size_type n1, const charT* x) const {
          return substr(pos1, n1).compare(basic_string_view(x));
      }
  
      STX_CONSTEXPR14 int compare(size_type pos1, size_type n1,
                                        const charT* x, size_type n2) const {
          return substr(pos1, n1).compare(basic_string_view(x, n2));
      }
  
      //  Searches
      constexpr bool starts_with(charT c) const noexcept {              // Boost extension
          return !empty() && traits::eq(c, front());
      }
  
      constexpr bool starts_with(basic_string_view x) const noexcept {  // Boost extension
          return len_ >= x.len_ && traits::compare(ptr_, x.ptr_, x.len_) == 0;
      }
  
      constexpr bool ends_with(charT c) const noexcept {                // Boost extension
          return !empty() && traits::eq(c, back());
      }
  
      constexpr bool ends_with(basic_string_view x) const noexcept {    // Boost extension
          return len_ >= x.len_ &&
                  traits::compare(ptr_ + len_ - x.len_, x.ptr_, x.len_) == 0;
      }
  
      //  find
      STX_CONSTEXPR14 size_type find(basic_string_view s, size_type pos = 0) const noexcept {
          if (pos > size())
              return npos;
          if (s.empty())
              return pos;
          const_iterator iter = std::search(this->cbegin() + pos, this->cend(),
                                            s.cbegin (), s.cend (), traits::eq);
          return iter == this->cend () ? npos : std::distance(this->cbegin (), iter);
      }
      STX_CONSTEXPR14 size_type find(charT c, size_type pos = 0) const noexcept
      { return find(basic_string_view(&c, 1), pos); }
      STX_CONSTEXPR14 size_type find(const charT* s, size_type pos, size_type n) const noexcept
      { return find(basic_string_view(s, n), pos); }
      STX_CONSTEXPR14 size_type find(const charT* s, size_type pos = 0) const noexcept
      { return find(basic_string_view(s), pos); }
  
      //  rfind
      STX_CONSTEXPR14 size_type rfind(basic_string_view s, size_type pos = npos) const noexcept {
          if (len_ < s.len_)
              return npos;
          if (pos > len_ - s.len_)
              pos = len_ - s.len_;
          if (s.len_ == 0u)     // an empty string is always found
              return pos;
          for (const charT* cur = ptr_ + pos; ; --cur) {
              if (traits::compare(cur, s.ptr_, s.len_) == 0)
                  return cur - ptr_;
              if (cur == ptr_)
                  return npos;
          };
      }
      STX_CONSTEXPR14 size_type rfind(charT c, size_type pos = npos) const noexcept
      { return rfind(basic_string_view(&c, 1), pos); }
      STX_CONSTEXPR14 size_type rfind(const charT* s, size_type pos, size_type n) const noexcept
      { return rfind(basic_string_view(s, n), pos); }
      STX_CONSTEXPR14 size_type rfind(const charT* s, size_type pos = npos) const noexcept
      { return rfind(basic_string_view(s), pos); }
  
      //  find_first_of
      STX_CONSTEXPR14 size_type find_first_of(basic_string_view s, size_type pos = 0) const noexcept {
          if (pos >= len_ || s.len_ == 0)
              return npos;
          const_iterator iter = std::find_first_of
                  (this->cbegin () + pos, this->cend (), s.cbegin (), s.cend (), traits::eq);
          return iter == this->cend () ? npos : std::distance ( this->cbegin (), iter );
      }
      STX_CONSTEXPR14 size_type find_first_of(charT c, size_type pos = 0) const noexcept
      { return find_first_of(basic_string_view(&c, 1), pos); }
      STX_CONSTEXPR14 size_type find_first_of(const charT* s, size_type pos, size_type n) const noexcept
      { return find_first_of(basic_string_view(s, n), pos); }
      STX_CONSTEXPR14 size_type find_first_of(const charT* s, size_type pos = 0) const noexcept
      { return find_first_of(basic_string_view(s), pos); }
  
      //  find_last_of
      STX_CONSTEXPR14 size_type find_last_of(basic_string_view s, size_type pos = npos) const noexcept {
          if (s.len_ == 0u)
              return npos;
          if (pos >= len_)
              pos = 0;
          else
              pos = len_ - (pos+1);
          const_reverse_iterator iter = std::find_first_of
                  ( this->crbegin () + pos, this->crend (), s.cbegin (), s.cend (), traits::eq );
          return iter == this->crend () ? npos : reverse_distance ( this->crbegin (), iter);
      }
      STX_CONSTEXPR14 size_type find_last_of(charT c, size_type pos = npos) const noexcept
      { return find_last_of(basic_string_view(&c, 1), pos); }
      STX_CONSTEXPR14 size_type find_last_of(const charT* s, size_type pos, size_type n) const noexcept
      { return find_last_of(basic_string_view(s, n), pos); }
      STX_CONSTEXPR14 size_type find_last_of(const charT* s, size_type pos = npos) const noexcept
      { return find_last_of(basic_string_view(s), pos); }
  
      //  find_first_not_of
      STX_CONSTEXPR14 size_type find_first_not_of(basic_string_view s, size_type pos = 0) const noexcept {
          if (pos >= len_)
              return npos;
          if (s.len_ == 0)
              return pos;
          const_iterator iter = find_not_of ( this->cbegin () + pos, this->cend (), s );
          return iter == this->cend () ? npos : std::distance ( this->cbegin (), iter );
      }
      STX_CONSTEXPR14 size_type find_first_not_of(charT c, size_type pos = 0) const noexcept
      { return find_first_not_of(basic_string_view(&c, 1), pos); }
      STX_CONSTEXPR14 size_type find_first_not_of(const charT* s, size_type pos, size_type n) const noexcept
      { return find_first_not_of(basic_string_view(s, n), pos); }
      STX_CONSTEXPR14 size_type find_first_not_of(const charT* s, size_type pos = 0) const noexcept
      { return find_first_not_of(basic_string_view(s), pos); }
  
      //  find_last_not_of
      STX_CONSTEXPR14 size_type find_last_not_of(basic_string_view s, size_type pos = npos) const noexcept {
          if (pos >= len_)
              pos = len_ - 1;
          if (s.len_ == 0u)
              return pos;
          pos = len_ - (pos+1);
          const_reverse_iterator iter = find_not_of ( this->crbegin () + pos, this->crend (), s );
          return iter == this->crend () ? npos : reverse_distance ( this->crbegin (), iter );
      }
      STX_CONSTEXPR14 size_type find_last_not_of(charT c, size_type pos = npos) const noexcept
      { return find_last_not_of(basic_string_view(&c, 1), pos); }
      STX_CONSTEXPR14 size_type find_last_not_of(const charT* s, size_type pos, size_type n) const noexcept
      { return find_last_not_of(basic_string_view(s, n), pos); }
      STX_CONSTEXPR14 size_type find_last_not_of(const charT* s, size_type pos = npos) const noexcept
      { return find_last_not_of(basic_string_view(s), pos); }
  
  private:
      template <typename r_iter>
      size_type reverse_distance(r_iter first, r_iter last) const noexcept {
          // Portability note here: std::distance is not NOEXCEPT, but calling it with a string_view::reverse_iterator will not throw.
          return len_ - 1 - std::distance ( first, last );
      }
  
      template <typename Iterator>
      Iterator find_not_of(Iterator first, Iterator last, basic_string_view s) const noexcept {
          for (; first != last ; ++first)
              if ( 0 == traits::find(s.ptr_, s.len_, *first))
                  return first;
          return last;
      }
  
      const charT *ptr_;
      std::size_t len_;
  };
  
  
  //  Comparison operators
  //  Equality
  template<typename charT, typename traits>
  inline bool operator==(basic_string_view<charT, traits> x,
                         basic_string_view<charT, traits> y) noexcept {
      if (x.size () != y.size ()) return false;
      return x.compare(y) == 0;
  }
  
  //  Inequality
  template<typename charT, typename traits>
  inline bool operator!=(basic_string_view<charT, traits> x,
                         basic_string_view<charT, traits> y) noexcept {
      if ( x.size () != y.size ()) return true;
      return x.compare(y) != 0;
  }
  
  //  Less than
  template<typename charT, typename traits>
  inline bool operator<(basic_string_view<charT, traits> x,
                        basic_string_view<charT, traits> y) noexcept {
      return x.compare(y) < 0;
  }
  
  //  Greater than
  template<typename charT, typename traits>
  inline bool operator>(basic_string_view<charT, traits> x,
                        basic_string_view<charT, traits> y) noexcept {
      return x.compare(y) > 0;
  }
  
  //  Less than or equal to
  template<typename charT, typename traits>
  inline bool operator<=(basic_string_view<charT, traits> x,
                         basic_string_view<charT, traits> y) noexcept {
      return x.compare(y) <= 0;
  }
  
  //  Greater than or equal to
  template<typename charT, typename traits>
  inline bool operator>=(basic_string_view<charT, traits> x,
                         basic_string_view<charT, traits> y) noexcept {
      return x.compare(y) >= 0;
  }
  
  // "sufficient additional overloads of comparison functions"
  template<typename charT, typename traits, typename Allocator>
  inline bool operator==(basic_string_view<charT, traits> x,
                         const std::basic_string<charT, traits, Allocator> & y) noexcept {
      return x == basic_string_view<charT, traits>(y);
  }
  
  template<typename charT, typename traits, typename Allocator>
  inline bool operator==(const std::basic_string<charT, traits, Allocator> & x,
                         basic_string_view<charT, traits> y) noexcept {
      return basic_string_view<charT, traits>(x) == y;
  }
  
  template<typename charT, typename traits>
  inline bool operator==(basic_string_view<charT, traits> x,
                         const charT * y) noexcept {
      return x == basic_string_view<charT, traits>(y);
  }
  
  template<typename charT, typename traits>
  inline bool operator==(const charT * x,
                         basic_string_view<charT, traits> y) noexcept {
      return basic_string_view<charT, traits>(x) == y;
  }
  
  template<typename charT, typename traits, typename Allocator>
  inline bool operator!=(basic_string_view<charT, traits> x,
                         const std::basic_string<charT, traits, Allocator> & y) noexcept {
      return x != basic_string_view<charT, traits>(y);
  }
  
  template<typename charT, typename traits, typename Allocator>
  inline bool operator!=(const std::basic_string<charT, traits, Allocator> & x,
                         basic_string_view<charT, traits> y) noexcept {
      return basic_string_view<charT, traits>(x) != y;
  }
  
  template<typename charT, typename traits>
  inline bool operator!=(basic_string_view<charT, traits> x,
                         const charT * y) noexcept {
      return x != basic_string_view<charT, traits>(y);
  }
  
  template<typename charT, typename traits>
  inline bool operator!=(const charT * x,
                         basic_string_view<charT, traits> y) noexcept {
      return basic_string_view<charT, traits>(x) != y;
  }
  
  template<typename charT, typename traits, typename Allocator>
  inline bool operator<(basic_string_view<charT, traits> x,
                        const std::basic_string<charT, traits, Allocator> & y) noexcept {
      return x < basic_string_view<charT, traits>(y);
  }
  
  template<typename charT, typename traits, typename Allocator>
  inline bool operator<(const std::basic_string<charT, traits, Allocator> & x,
                        basic_string_view<charT, traits> y) noexcept {
      return basic_string_view<charT, traits>(x) < y;
  }
  
  template<typename charT, typename traits>
  inline bool operator<(basic_string_view<charT, traits> x,
                        const charT * y) noexcept {
      return x < basic_string_view<charT, traits>(y);
  }
  
  template<typename charT, typename traits>
  inline bool operator<(const charT * x,
                        basic_string_view<charT, traits> y) noexcept {
      return basic_string_view<charT, traits>(x) < y;
  }
  
  template<typename charT, typename traits, typename Allocator>
  inline bool operator>(basic_string_view<charT, traits> x,
                        const std::basic_string<charT, traits, Allocator> & y) noexcept {
      return x > basic_string_view<charT, traits>(y);
  }
  
  template<typename charT, typename traits, typename Allocator>
  inline bool operator>(const std::basic_string<charT, traits, Allocator> & x,
                        basic_string_view<charT, traits> y) noexcept {
      return basic_string_view<charT, traits>(x) > y;
  }
  
  template<typename charT, typename traits>
  inline bool operator>(basic_string_view<charT, traits> x,
                        const charT * y) noexcept {
      return x > basic_string_view<charT, traits>(y);
  }
  
  template<typename charT, typename traits>
  inline bool operator>(const charT * x,
                        basic_string_view<charT, traits> y) noexcept {
      return basic_string_view<charT, traits>(x) > y;
  }
  
  template<typename charT, typename traits, typename Allocator>
  inline bool operator<=(basic_string_view<charT, traits> x,
                         const std::basic_string<charT, traits, Allocator> & y) noexcept {
      return x <= basic_string_view<charT, traits>(y);
  }
  
  template<typename charT, typename traits, typename Allocator>
  inline bool operator<=(const std::basic_string<charT, traits, Allocator> & x,
                         basic_string_view<charT, traits> y) noexcept {
      return basic_string_view<charT, traits>(x) <= y;
  }
  
  template<typename charT, typename traits>
  inline bool operator<=(basic_string_view<charT, traits> x,
                         const charT * y) noexcept {
      return x <= basic_string_view<charT, traits>(y);
  }
  
  template<typename charT, typename traits>
  inline bool operator<=(const charT * x,
                         basic_string_view<charT, traits> y) noexcept {
      return basic_string_view<charT, traits>(x) <= y;
  }
  
  template<typename charT, typename traits, typename Allocator>
  inline bool operator>=(basic_string_view<charT, traits> x,
                         const std::basic_string<charT, traits, Allocator> & y) noexcept {
      return x >= basic_string_view<charT, traits>(y);
  }
  
  template<typename charT, typename traits, typename Allocator>
  inline bool operator>=(const std::basic_string<charT, traits, Allocator> & x,
                         basic_string_view<charT, traits> y) noexcept {
      return basic_string_view<charT, traits>(x) >= y;
  }
  
  template<typename charT, typename traits>
  inline bool operator>=(basic_string_view<charT, traits> x,
                         const charT * y) noexcept {
      return x >= basic_string_view<charT, traits>(y);
  }
  
  template<typename charT, typename traits>
  inline bool operator>=(const charT * x,
                         basic_string_view<charT, traits> y) noexcept {
      return basic_string_view<charT, traits>(x) >= y;
  }
  
  namespace detail {
  
  template<class charT, class traits>
  inline void sv_insert_fill_chars(std::basic_ostream<charT, traits>& os, std::size_t n) {
      enum { chunk_size = 8 };
      charT fill_chars[chunk_size];
      std::fill_n(fill_chars, static_cast< std::size_t >(chunk_size), os.fill());
      for (; n >= chunk_size && os.good(); n -= chunk_size)
          os.write(fill_chars, static_cast< std::size_t >(chunk_size));
      if (n > 0 && os.good())
          os.write(fill_chars, n);
  }
  
  template<class charT, class traits>
  void sv_insert_aligned(std::basic_ostream<charT, traits>& os, const basic_string_view<charT,traits>& str) {
      const std::size_t size = str.size();
      const std::size_t alignment_size = static_cast< std::size_t >(os.width()) - size;
      const bool align_left = (os.flags() & std::basic_ostream<charT, traits>::adjustfield) == std::basic_ostream<charT, traits>::left;
      if (!align_left) {
          detail::sv_insert_fill_chars(os, alignment_size);
          if (os.good())
              os.write(str.data(), size);
      }
      else {
          os.write(str.data(), size);
          if (os.good())
              detail::sv_insert_fill_chars(os, alignment_size);
      }
  }
  
  } // namespace detail
  
  // Inserter
  template<class charT, class traits>
  inline std::basic_ostream<charT, traits>&
  operator<<(std::basic_ostream<charT, traits>& os,
             const basic_string_view<charT,traits>& str) {
      if (os.good()) {
          const std::size_t size = str.size();
          const std::size_t w = static_cast< std::size_t >(os.width());
          if (w <= size)
              os.write(str.data(), size);
          else
              detail::sv_insert_aligned(os, str);
          os.width(0);
      }
      return os;
  }
  
  #if 0
  // numeric conversions
      //
      //  These are short-term implementations.
      //  In a production environment, I would rather avoid the copying.
      //
      inline int stoi (string_view str, size_t* idx=0, int base=10) {
          return std::stoi ( std::string(str), idx, base );
          }
  
      inline long stol (string_view str, size_t* idx=0, int base=10) {
          return std::stol ( std::string(str), idx, base );
          }
  
      inline unsigned long stoul (string_view str, size_t* idx=0, int base=10) {
          return std::stoul ( std::string(str), idx, base );
          }
  
      inline long long stoll (string_view str, size_t* idx=0, int base=10) {
          return std::stoll ( std::string(str), idx, base );
          }
  
      inline unsigned long long stoull (string_view str, size_t* idx=0, int base=10) {
          return std::stoull ( std::string(str), idx, base );
          }
  
      inline float stof (string_view str, size_t* idx=0) {
          return std::stof ( std::string(str), idx );
          }
  
      inline double stod (string_view str, size_t* idx=0) {
          return std::stod ( std::string(str), idx );
          }
  
      inline long double stold (string_view str, size_t* idx=0)  {
          return std::stold ( std::string(str), idx );
          }
  
      inline int  stoi (wstring_view str, size_t* idx=0, int base=10) {
          return std::stoi ( std::wstring(str), idx, base );
          }
  
      inline long stol (wstring_view str, size_t* idx=0, int base=10) {
          return std::stol ( std::wstring(str), idx, base );
          }
  
      inline unsigned long stoul (wstring_view str, size_t* idx=0, int base=10) {
          return std::stoul ( std::wstring(str), idx, base );
          }
  
      inline long long stoll (wstring_view str, size_t* idx=0, int base=10) {
          return std::stoll ( std::wstring(str), idx, base );
          }
  
      inline unsigned long long stoull (wstring_view str, size_t* idx=0, int base=10) {
          return std::stoull ( std::wstring(str), idx, base );
          }
  
      inline float  stof (wstring_view str, size_t* idx=0) {
          return std::stof ( std::wstring(str), idx );
          }
  
      inline double stod (wstring_view str, size_t* idx=0) {
          return std::stod ( std::wstring(str), idx );
          }
  
      inline long double stold (wstring_view str, size_t* idx=0) {
          return std::stold ( std::wstring(str), idx );
          }
  #endif
  
  using string_view = basic_string_view<char, std::char_traits<char>>;
  using u16string_view = basic_string_view<char16_t, std::char_traits<char16_t>>;
  using u32string_view = basic_string_view<char32_t, std::char_traits<char32_t>>;
  using wstring_view = basic_string_view<wchar_t, std::char_traits<wchar_t>>;
  
  } // end namespace
  
  #if 0
  namespace std {
      // Hashing
      template<> struct hash<STX_NAMESPACE_NAME::string_view>;
      template<> struct hash<STX_NAMESPACE_NAME::u16string_view>;
      template<> struct hash<STX_NAMESPACE_NAME::u32string_view>;
      template<> struct hash<STX_NAMESPACE_NAME::wstring_view>;
  }
  #endif
  
  #endif // STX_HAVE_STD_STRING_VIEW
  
  #endif // STX_STRING_VIEW_HPP_INCLUDED
  