text: // Formatting library for C++ - the core API
  //
  // Copyright (c) 2012 - present, Victor Zverovich
  // All rights reserved.
  //
  // For the license information refer to format.h.
  
  #ifndef FMT_CORE_H_
  #define FMT_CORE_H_
  
  #include <cassert>
  #include <cstdio>  // std::FILE
  #include <cstring>
  #include <iterator>
  #include <string>
  #include <type_traits>
  
  // The fmt library version in the form major * 10000 + minor * 100 + patch.
  #define FMT_VERSION 50202
  
  #ifdef __has_feature
  # define FMT_HAS_FEATURE(x) __has_feature(x)
  #else
  # define FMT_HAS_FEATURE(x) 0
  #endif
  
  #if defined(__has_include) && !defined(__INTELLISENSE__) && \
      !(defined(__INTEL_COMPILER) && __INTEL_COMPILER < 1600)
  # define FMT_HAS_INCLUDE(x) __has_include(x)
  #else
  # define FMT_HAS_INCLUDE(x) 0
  #endif
  
  #ifdef __has_cpp_attribute
  # define FMT_HAS_CPP_ATTRIBUTE(x) __has_cpp_attribute(x)
  #else
  # define FMT_HAS_CPP_ATTRIBUTE(x) 0
  #endif
  
  #if defined(__GNUC__) && !defined(__clang__)
  # define FMT_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
  #else
  # define FMT_GCC_VERSION 0
  #endif
  
  #if __cplusplus >= 201103L || defined(__GXX_EXPERIMENTAL_CXX0X__)
  # define FMT_HAS_GXX_CXX11 FMT_GCC_VERSION
  #else
  # define FMT_HAS_GXX_CXX11 0
  #endif
  
  #ifdef _MSC_VER
  # define FMT_MSC_VER _MSC_VER
  #else
  # define FMT_MSC_VER 0
  #endif
  
  // Check if relaxed C++14 constexpr is supported.
  // GCC doesn't allow throw in constexpr until version 6 (bug 67371).
  #ifndef FMT_USE_CONSTEXPR
  # define FMT_USE_CONSTEXPR \
    (FMT_HAS_FEATURE(cxx_relaxed_constexpr) || FMT_MSC_VER >= 1910 || \
     (FMT_GCC_VERSION >= 600 && __cplusplus >= 201402L))
  #endif
  #if FMT_USE_CONSTEXPR
  # define FMT_CONSTEXPR constexpr
  # define FMT_CONSTEXPR_DECL constexpr
  #else
  # define FMT_CONSTEXPR inline
  # define FMT_CONSTEXPR_DECL
  #endif
  
  #ifndef FMT_USE_CONSTEXPR11
  # define FMT_USE_CONSTEXPR11 \
      (FMT_USE_CONSTEXPR || FMT_GCC_VERSION >= 406 || FMT_MSC_VER >= 1900)
  #endif
  #if FMT_USE_CONSTEXPR11
  # define FMT_CONSTEXPR11 constexpr
  #else
  # define FMT_CONSTEXPR11
  #endif
  
  #ifndef FMT_OVERRIDE
  # if FMT_HAS_FEATURE(cxx_override) || \
       (FMT_GCC_VERSION >= 408 && FMT_HAS_GXX_CXX11) || FMT_MSC_VER >= 1900
  #  define FMT_OVERRIDE override
  # else
  #  define FMT_OVERRIDE
  # endif
  #endif
  
  #if FMT_HAS_FEATURE(cxx_explicit_conversions) || \
      FMT_GCC_VERSION >= 405 || FMT_MSC_VER >= 1800
  # define FMT_USE_EXPLICIT 1
  # define FMT_EXPLICIT explicit
  #else
  # define FMT_USE_EXPLICIT 0
  # define FMT_EXPLICIT
  #endif
  
  #ifndef FMT_NULL
  # if FMT_HAS_FEATURE(cxx_nullptr) || \
     (FMT_GCC_VERSION >= 408 && FMT_HAS_GXX_CXX11) || FMT_MSC_VER >= 1600
  #  define FMT_NULL nullptr
  #  define FMT_USE_NULLPTR 1
  # else
  #  define FMT_NULL NULL
  # endif
  #endif
  #ifndef FMT_USE_NULLPTR
  # define FMT_USE_NULLPTR 0
  #endif
  
  // Check if exceptions are disabled.
  #ifndef FMT_EXCEPTIONS
  # if (defined(__GNUC__) && !defined(__EXCEPTIONS)) || \
       FMT_MSC_VER && !_HAS_EXCEPTIONS
  #  define FMT_EXCEPTIONS 0
  # else
  #  define FMT_EXCEPTIONS 1
  # endif
  #endif
  
  // Define FMT_USE_NOEXCEPT to make fmt use noexcept (C++11 feature).
  #ifndef FMT_USE_NOEXCEPT
  # define FMT_USE_NOEXCEPT 0
  #endif
  
  #if FMT_USE_NOEXCEPT || FMT_HAS_FEATURE(cxx_noexcept) || \
      (FMT_GCC_VERSION >= 408 && FMT_HAS_GXX_CXX11) || FMT_MSC_VER >= 1900
  # define FMT_DETECTED_NOEXCEPT noexcept
  # define FMT_HAS_CXX11_NOEXCEPT 1
  #else
  # define FMT_DETECTED_NOEXCEPT throw()
  # define FMT_HAS_CXX11_NOEXCEPT 0
  #endif
  
  #ifndef FMT_NOEXCEPT
  # if FMT_EXCEPTIONS || FMT_HAS_CXX11_NOEXCEPT
  #  define FMT_NOEXCEPT FMT_DETECTED_NOEXCEPT
  # else
  #  define FMT_NOEXCEPT
  # endif
  #endif
  
  #ifndef FMT_BEGIN_NAMESPACE
  # if FMT_HAS_FEATURE(cxx_inline_namespaces) || FMT_GCC_VERSION >= 404 || \
       FMT_MSC_VER >= 1900
  #  define FMT_INLINE_NAMESPACE inline namespace
  #  define FMT_END_NAMESPACE }}
  # else
  #  define FMT_INLINE_NAMESPACE namespace
  #  define FMT_END_NAMESPACE } using namespace v5; }
  # endif
  # define FMT_BEGIN_NAMESPACE namespace fmt { FMT_INLINE_NAMESPACE v5 {
  #endif
  
  #if !defined(FMT_HEADER_ONLY) && defined(_WIN32)
  # ifdef FMT_EXPORT
  #  define FMT_API __declspec(dllexport)
  # elif defined(FMT_SHARED)
  #  define FMT_API __declspec(dllimport)
  # endif
  #endif
  #ifndef FMT_API
  # define FMT_API
  #endif
  
  #ifndef FMT_ASSERT
  # define FMT_ASSERT(condition, message) assert((condition) && message)
  #endif
  
  // libc++ supports string_view in pre-c++17.
  #if (FMT_HAS_INCLUDE(<string_view>) && \
        (__cplusplus > 201402L || defined(_LIBCPP_VERSION))) || \
      (defined(_MSVC_LANG) && _MSVC_LANG > 201402L && _MSC_VER >= 1910)
  # include <string_view>
  # define FMT_STRING_VIEW std::basic_string_view
  #elif FMT_HAS_INCLUDE(<experimental/string_view>) && __cplusplus >= 201402L
  # include <experimental/string_view>
  # define FMT_STRING_VIEW std::experimental::basic_string_view
  #endif
  
  // std::result_of is defined in <functional> in gcc 4.4.
  #if FMT_GCC_VERSION && FMT_GCC_VERSION <= 404
  # include <functional>
  #endif
  
  FMT_BEGIN_NAMESPACE
  namespace internal {
  
  // An implementation of declval for pre-C++11 compilers such as gcc 4.
  template <typename T>
  typename std::add_rvalue_reference<T>::type declval() FMT_NOEXCEPT;
  
  template <typename>
  struct result_of;
  
  template <typename F, typename... Args>
  struct result_of<F(Args...)> {
    // A workaround for gcc 4.4 that doesn't allow F to be a reference.
    typedef typename std::result_of<
      typename std::remove_reference<F>::type(Args...)>::type type;
  };
  
  // Casts nonnegative integer to unsigned.
  template <typename Int>
  FMT_CONSTEXPR typename std::make_unsigned<Int>::type to_unsigned(Int value) {
    FMT_ASSERT(value >= 0, "negative value");
    return static_cast<typename std::make_unsigned<Int>::type>(value);
  }
  
  /** A contiguous memory buffer with an optional growing ability. */
  template <typename T>
  class basic_buffer {
   private:
    basic_buffer(const basic_buffer &) = delete;
    void operator=(const basic_buffer &) = delete;
  
    T *ptr_;
    std::size_t size_;
    std::size_t capacity_;
  
   protected:
    // Don't initialize ptr_ since it is not accessed to save a few cycles.
    basic_buffer(std::size_t sz) FMT_NOEXCEPT: size_(sz), capacity_(sz) {}
  
    basic_buffer(T *p = FMT_NULL, std::size_t sz = 0, std::size_t cap = 0)
      FMT_NOEXCEPT: ptr_(p), size_(sz), capacity_(cap) {}
  
    /** Sets the buffer data and capacity. */
    void set(T *buf_data, std::size_t buf_capacity) FMT_NOEXCEPT {
      ptr_ = buf_data;
      capacity_ = buf_capacity;
    }
  
    /** Increases the buffer capacity to hold at least *capacity* elements. */
    virtual void grow(std::size_t capacity) = 0;
  
   public:
    typedef T value_type;
    typedef const T &const_reference;
  
    virtual ~basic_buffer() {}
  
    T *begin() FMT_NOEXCEPT { return ptr_; }
    T *end() FMT_NOEXCEPT { return ptr_ + size_; }
  
    /** Returns the size of this buffer. */
    std::size_t size() const FMT_NOEXCEPT { return size_; }
  
    /** Returns the capacity of this buffer. */
    std::size_t capacity() const FMT_NOEXCEPT { return capacity_; }
  
    /** Returns a pointer to the buffer data. */
    T *data() FMT_NOEXCEPT { return ptr_; }
  
    /** Returns a pointer to the buffer data. */
    const T *data() const FMT_NOEXCEPT { return ptr_; }
  
    /**
      Resizes the buffer. If T is a POD type new elements may not be initialized.
     */
    void resize(std::size_t new_size) {
      reserve(new_size);
      size_ = new_size;
    }
  
    /** Clears this buffer. */
    void clear() { size_ = 0; }
  
    /** Reserves space to store at least *capacity* elements. */
    void reserve(std::size_t new_capacity) {
      if (new_capacity > capacity_)
        grow(new_capacity);
    }
  
    void push_back(const T &value) {
      reserve(size_ + 1);
      ptr_[size_++] = value;
    }
  
    /** Appends data to the end of the buffer. */
    template <typename U>
    void append(const U *begin, const U *end);
  
    T &operator[](std::size_t index) { return ptr_[index]; }
    const T &operator[](std::size_t index) const { return ptr_[index]; }
  };
  
  typedef basic_buffer<char> buffer;
  typedef basic_buffer<wchar_t> wbuffer;
  
  // A container-backed buffer.
  template <typename Container>
  class container_buffer : public basic_buffer<typename Container::value_type> {
   private:
    Container &container_;
  
   protected:
    void grow(std::size_t capacity) FMT_OVERRIDE {
      container_.resize(capacity);
      this->set(&container_[0], capacity);
    }
  
   public:
    explicit container_buffer(Container &c)
      : basic_buffer<typename Container::value_type>(c.size()), container_(c) {}
  };
  
  // Extracts a reference to the container from back_insert_iterator.
  template <typename Container>
  inline Container &get_container(std::back_insert_iterator<Container> it) {
    typedef std::back_insert_iterator<Container> bi_iterator;
    struct accessor: bi_iterator {
      accessor(bi_iterator iter) : bi_iterator(iter) {}
      using bi_iterator::container;
    };
    return *accessor(it).container;
  }
  
  struct error_handler {
    FMT_CONSTEXPR error_handler() {}
    FMT_CONSTEXPR error_handler(const error_handler &) {}
  
    // This function is intentionally not constexpr to give a compile-time error.
    FMT_API void on_error(const char *message);
  };
  
  template <typename T>
  struct no_formatter_error : std::false_type {};
  }  // namespace internal
  
  #if FMT_GCC_VERSION && FMT_GCC_VERSION < 405
  template <typename... T>
  struct is_constructible: std::false_type {};
  #else
  template <typename... T>
  struct is_constructible : std::is_constructible<T...> {};
  #endif
  
  /**
    An implementation of ``std::basic_string_view`` for pre-C++17. It provides a
    subset of the API. ``fmt::basic_string_view`` is used for format strings even
    if ``std::string_view`` is available to prevent issues when a library is
    compiled with a different ``-std`` option than the client code (which is not
    recommended).
   */
  template <typename Char>
  class basic_string_view {
   private:
    const Char *data_;
    size_t size_;
  
   public:
    typedef Char char_type;
    typedef const Char *iterator;
  
    FMT_CONSTEXPR basic_string_view() FMT_NOEXCEPT : data_(FMT_NULL), size_(0) {}
  
    /** Constructs a string reference object from a C string and a size. */
    FMT_CONSTEXPR basic_string_view(const Char *s, size_t count) FMT_NOEXCEPT
      : data_(s), size_(count) {}
  
    /**
      \rst
      Constructs a string reference object from a C string computing
      the size with ``std::char_traits<Char>::length``.
      \endrst
     */
    basic_string_view(const Char *s)
      : data_(s), size_(std::char_traits<Char>::length(s)) {}
  
    /** Constructs a string reference from a ``std::basic_string`` object. */
    template <typename Alloc>
    FMT_CONSTEXPR basic_string_view(
        const std::basic_string<Char, Alloc> &s) FMT_NOEXCEPT
    : data_(s.data()), size_(s.size()) {}
  
  #ifdef FMT_STRING_VIEW
    FMT_CONSTEXPR basic_string_view(FMT_STRING_VIEW<Char> s) FMT_NOEXCEPT
    : data_(s.data()), size_(s.size()) {}
  #endif
  
    /** Returns a pointer to the string data. */
    FMT_CONSTEXPR const Char *data() const { return data_; }
  
    /** Returns the string size. */
    FMT_CONSTEXPR size_t size() const { return size_; }
  
    FMT_CONSTEXPR iterator begin() const { return data_; }
    FMT_CONSTEXPR iterator end() const { return data_ + size_; }
  
    FMT_CONSTEXPR void remove_prefix(size_t n) {
      data_ += n;
      size_ -= n;
    }
  
    // Lexicographically compare this string reference to other.
    int compare(basic_string_view other) const {
      size_t str_size = size_ < other.size_ ? size_ : other.size_;
      int result = std::char_traits<Char>::compare(data_, other.data_, str_size);
      if (result == 0)
        result = size_ == other.size_ ? 0 : (size_ < other.size_ ? -1 : 1);
      return result;
    }
  
    friend bool operator==(basic_string_view lhs, basic_string_view rhs) {
      return lhs.compare(rhs) == 0;
    }
    friend bool operator!=(basic_string_view lhs, basic_string_view rhs) {
      return lhs.compare(rhs) != 0;
    }
    friend bool operator<(basic_string_view lhs, basic_string_view rhs) {
      return lhs.compare(rhs) < 0;
    }
    friend bool operator<=(basic_string_view lhs, basic_string_view rhs) {
      return lhs.compare(rhs) <= 0;
    }
    friend bool operator>(basic_string_view lhs, basic_string_view rhs) {
      return lhs.compare(rhs) > 0;
    }
    friend bool operator>=(basic_string_view lhs, basic_string_view rhs) {
      return lhs.compare(rhs) >= 0;
    }
  };
  
  typedef basic_string_view<char> string_view;
  typedef basic_string_view<wchar_t> wstring_view;
  
  /**
    \rst
    The function ``to_string_view`` adapts non-intrusively any kind of string or
    string-like type if the user provides a (possibly templated) overload of
    ``to_string_view`` which takes an instance of the string class
    ``StringType<Char>`` and returns a ``fmt::basic_string_view<Char>``.
    The conversion function must live in the very same namespace as
    ``StringType<Char>`` to be picked up by ADL. Non-templated string types
    like f.e. QString must return a ``basic_string_view`` with a fixed matching
    char type.
  
    **Example**::
  
      namespace my_ns {
      inline string_view to_string_view(const my_string &s) {
        return {s.data(), s.length()};
      }
      }
  
      std::string message = fmt::format(my_string("The answer is {}"), 42);
    \endrst
   */
  template <typename Char>
  inline basic_string_view<Char>
    to_string_view(basic_string_view<Char> s) { return s; }
  
  template <typename Char>
  inline basic_string_view<Char>
    to_string_view(const std::basic_string<Char> &s) { return s; }
  
  template <typename Char>
  inline basic_string_view<Char> to_string_view(const Char *s) { return s; }
  
  #ifdef FMT_STRING_VIEW
  template <typename Char>
  inline basic_string_view<Char>
    to_string_view(FMT_STRING_VIEW<Char> s) { return s; }
  #endif
  
  // A base class for compile-time strings. It is defined in the fmt namespace to
  // make formatting functions visible via ADL, e.g. format(fmt("{}"), 42).
  struct compile_string {};
  
  template <typename S>
  struct is_compile_string : std::is_base_of<compile_string, S> {};
  
  template <
    typename S,
    typename Enable = typename std::enable_if<is_compile_string<S>::value>::type>
  FMT_CONSTEXPR basic_string_view<typename S::char_type>
    to_string_view(const S &s) { return s; }
  
  template <typename Context>
  class basic_format_arg;
  
  template <typename Context>
  class basic_format_args;
  
  // A formatter for objects of type T.
  template <typename T, typename Char = char, typename Enable = void>
  struct formatter {
    static_assert(internal::no_formatter_error<T>::value,
      "don't know how to format the type, include fmt/ostream.h if it provides "
      "an operator<< that should be used");
  
    // The following functions are not defined intentionally.
    template <typename ParseContext>
    typename ParseContext::iterator parse(ParseContext &);
    template <typename FormatContext>
    auto format(const T &val, FormatContext &ctx) -> decltype(ctx.out());
  };
  
  template <typename T, typename Char, typename Enable = void>
  struct convert_to_int: std::integral_constant<
    bool, !std::is_arithmetic<T>::value && std::is_convertible<T, int>::value> {};
  
  namespace internal {
  
  struct dummy_string_view { typedef void char_type; };
  dummy_string_view to_string_view(...);
  using fmt::v5::to_string_view;
  
  // Specifies whether S is a string type convertible to fmt::basic_string_view.
  template <typename S>
  struct is_string : std::integral_constant<bool, !std::is_same<
      dummy_string_view, decltype(to_string_view(declval<S>()))>::value> {};
  
  template <typename S>
  struct char_t {
    typedef decltype(to_string_view(declval<S>())) result;
    typedef typename result::char_type type;
  };
  
  template <typename Char>
  struct named_arg_base;
  
  template <typename T, typename Char>
  struct named_arg;
  
  enum type {
    none_type, named_arg_type,
    // Integer types should go first,
    int_type, uint_type, long_long_type, ulong_long_type, bool_type, char_type,
    last_integer_type = char_type,
    // followed by floating-point types.
    double_type, long_double_type, last_numeric_type = long_double_type,
    cstring_type, string_type, pointer_type, custom_type
  };
  
  FMT_CONSTEXPR bool is_integral(type t) {
    FMT_ASSERT(t != internal::named_arg_type, "invalid argument type");
    return t > internal::none_type && t <= internal::last_integer_type;
  }
  
  FMT_CONSTEXPR bool is_arithmetic(type t) {
    FMT_ASSERT(t != internal::named_arg_type, "invalid argument type");
    return t > internal::none_type && t <= internal::last_numeric_type;
  }
  
  template <typename Char>
  struct string_value {
    const Char *value;
    std::size_t size;
  };
  
  template <typename Context>
  struct custom_value {
    const void *value;
    void (*format)(const void *arg, Context &ctx);
  };
  
  // A formatting argument value.
  template <typename Context>
  class value {
   public:
    typedef typename Context::char_type char_type;
  
    union {
      int int_value;
      unsigned uint_value;
      long long long_long_value;
      unsigned long long ulong_long_value;
      double double_value;
      long double long_double_value;
      const void *pointer;
      string_value<char_type> string;
      string_value<signed char> sstring;
      string_value<unsigned char> ustring;
      custom_value<Context> custom;
    };
  
    FMT_CONSTEXPR value(int val = 0) : int_value(val) {}
    value(unsigned val) { uint_value = val; }
    value(long long val) { long_long_value = val; }
    value(unsigned long long val) { ulong_long_value = val; }
    value(double val) { double_value = val; }
    value(long double val) { long_double_value = val; }
    value(const char_type *val) { string.value = val; }
    value(const signed char *val) {
      static_assert(std::is_same<char, char_type>::value,
                    "incompatible string types");
      sstring.value = val;
    }
    value(const unsigned char *val) {
      static_assert(std::is_same<char, char_type>::value,
                    "incompatible string types");
      ustring.value = val;
    }
    value(basic_string_view<char_type> val) {
      string.value = val.data();
      string.size = val.size();
    }
    value(const void *val) { pointer = val; }
  
    template <typename T>
    explicit value(const T &val) {
      custom.value = &val;
      custom.format = &format_custom_arg<T>;
    }
  
    const named_arg_base<char_type> &as_named_arg() {
      return *static_cast<const named_arg_base<char_type>*>(pointer);
    }
  
   private:
    // Formats an argument of a custom type, such as a user-defined class.
    template <typename T>
    static void format_custom_arg(const void *arg, Context &ctx) {
      // Get the formatter type through the context to allow different contexts
      // have different extension points, e.g. `formatter<T>` for `format` and
      // `printf_formatter<T>` for `printf`.
      typename Context::template formatter_type<T>::type f;
      auto &&parse_ctx = ctx.parse_context();
      parse_ctx.advance_to(f.parse(parse_ctx));
      ctx.advance_to(f.format(*static_cast<const T*>(arg), ctx));
    }
  };
  
  // Value initializer used to delay conversion to value and reduce memory churn.
  template <typename Context, typename T, type TYPE>
  struct init {
    T val;
    static const type type_tag = TYPE;
  
    FMT_CONSTEXPR init(const T &v) : val(v) {}
    FMT_CONSTEXPR operator value<Context>() const { return value<Context>(val); }
  };
  
  template <typename Context, typename T>
  FMT_CONSTEXPR basic_format_arg<Context> make_arg(const T &value);
  
  #define FMT_MAKE_VALUE(TAG, ArgType, ValueType) \
    template <typename C> \
    FMT_CONSTEXPR init<C, ValueType, TAG> make_value(ArgType val) { \
      return static_cast<ValueType>(val); \
    }
  
  #define FMT_MAKE_VALUE_SAME(TAG, Type) \
    template <typename C> \
    FMT_CONSTEXPR init<C, Type, TAG> make_value(Type val) { return val; }
  
  FMT_MAKE_VALUE(bool_type, bool, int)
  FMT_MAKE_VALUE(int_type, short, int)
  FMT_MAKE_VALUE(uint_type, unsigned short, unsigned)
  FMT_MAKE_VALUE_SAME(int_type, int)
  FMT_MAKE_VALUE_SAME(uint_type, unsigned)
  
  // To minimize the number of types we need to deal with, long is translated
  // either to int or to long long depending on its size.
  typedef std::conditional<sizeof(long) == sizeof(int), int, long long>::type
          long_type;
  FMT_MAKE_VALUE(
      (sizeof(long) == sizeof(int) ? int_type : long_long_type), long, long_type)
  typedef std::conditional<sizeof(unsigned long) == sizeof(unsigned),
                           unsigned, unsigned long long>::type ulong_type;
  FMT_MAKE_VALUE(
      (sizeof(unsigned long) == sizeof(unsigned) ? uint_type : ulong_long_type),
      unsigned long, ulong_type)
  
  FMT_MAKE_VALUE_SAME(long_long_type, long long)
  FMT_MAKE_VALUE_SAME(ulong_long_type, unsigned long long)
  FMT_MAKE_VALUE(int_type, signed char, int)
  FMT_MAKE_VALUE(uint_type, unsigned char, unsigned)
  
  // This doesn't use FMT_MAKE_VALUE because of ambiguity in gcc 4.4.
  template <typename C, typename Char>
  FMT_CONSTEXPR typename std::enable_if<
    std::is_same<typename C::char_type, Char>::value,
    init<C, int, char_type>>::type make_value(Char val) { return val; }
  
  template <typename C>
  FMT_CONSTEXPR typename std::enable_if<
    !std::is_same<typename C::char_type, char>::value,
    init<C, int, char_type>>::type make_value(char val) { return val; }
  
  FMT_MAKE_VALUE(double_type, float, double)
  FMT_MAKE_VALUE_SAME(double_type, double)
  FMT_MAKE_VALUE_SAME(long_double_type, long double)
  
  // Formatting of wide strings into a narrow buffer and multibyte strings
  // into a wide buffer is disallowed (https://github.com/fmtlib/fmt/pull/606).
  FMT_MAKE_VALUE(cstring_type, typename C::char_type*,
                 const typename C::char_type*)
  FMT_MAKE_VALUE(cstring_type, const typename C::char_type*,
                 const typename C::char_type*)
  
  FMT_MAKE_VALUE(cstring_type, signed char*, const signed char*)
  FMT_MAKE_VALUE_SAME(cstring_type, const signed char*)
  FMT_MAKE_VALUE(cstring_type, unsigned char*, const unsigned char*)
  FMT_MAKE_VALUE_SAME(cstring_type, const unsigned char*)
  FMT_MAKE_VALUE_SAME(string_type, basic_string_view<typename C::char_type>)
  FMT_MAKE_VALUE(string_type,
                 typename basic_string_view<typename C::char_type>::type,
                 basic_string_view<typename C::char_type>)
  FMT_MAKE_VALUE(string_type, const std::basic_string<typename C::char_type>&,
                 basic_string_view<typename C::char_type>)
  FMT_MAKE_VALUE(pointer_type, void*, const void*)
  FMT_MAKE_VALUE_SAME(pointer_type, const void*)
  
  #if FMT_USE_NULLPTR
  FMT_MAKE_VALUE(pointer_type, std::nullptr_t, const void*)
  #endif
  
  // Formatting of arbitrary pointers is disallowed. If you want to output a
  // pointer cast it to "void *" or "const void *". In particular, this forbids
  // formatting of "[const] volatile char *" which is printed as bool by
  // iostreams.
  template <typename C, typename T>
  typename std::enable_if<!std::is_same<T, typename C::char_type>::value>::type
      make_value(const T *) {
    static_assert(!sizeof(T), "formatting of non-void pointers is disallowed");
  }
  
  template <typename C, typename T>
  inline typename std::enable_if<
      std::is_enum<T>::value && convert_to_int<T, typename C::char_type>::value,
      init<C, int, int_type>>::type
    make_value(const T &val) { return static_cast<int>(val); }
  
  template <typename C, typename T, typename Char = typename C::char_type>
  inline typename std::enable_if<
      is_constructible<basic_string_view<Char>, T>::value &&
      !internal::is_string<T>::value,
      init<C, basic_string_view<Char>, string_type>>::type
    make_value(const T &val) { return basic_string_view<Char>(val); }
  
  template <typename C, typename T, typename Char = typename C::char_type>
  inline typename std::enable_if<
      !convert_to_int<T, Char>::value && !std::is_same<T, Char>::value &&
      !std::is_convertible<T, basic_string_view<Char>>::value &&
      !is_constructible<basic_string_view<Char>, T>::value &&
      !internal::is_string<T>::value,
      // Implicit conversion to std::string is not handled here because it's
      // unsafe: https://github.com/fmtlib/fmt/issues/729
      init<C, const T &, custom_type>>::type
    make_value(const T &val) { return val; }
  
  template <typename C, typename T>
  init<C, const void*, named_arg_type>
      make_value(const named_arg<T, typename C::char_type> &val) {
    basic_format_arg<C> arg = make_arg<C>(val.value);
    std::memcpy(val.data, &arg, sizeof(arg));
    return static_cast<const void*>(&val);
  }
  
  template <typename C, typename S>
  FMT_CONSTEXPR11 typename std::enable_if<
    internal::is_string<S>::value,
    init<C, basic_string_view<typename C::char_type>, string_type>>::type
      make_value(const S &val) {
    // Handle adapted strings.
    static_assert(std::is_same<
      typename C::char_type, typename internal::char_t<S>::type>::value,
      "mismatch between char-types of context and argument");
    return to_string_view(val);
  }
  
  // Maximum number of arguments with packed types.
  enum { max_packed_args = 15 };
  enum : unsigned long long { is_unpacked_bit = 1ull << 63 };
  
  template <typename Context>
  class arg_map;
  }  // namespace internal
  
  // A formatting argument. It is a trivially copyable/constructible type to
  // allow storage in basic_memory_buffer.
  template <typename Context>
  class basic_format_arg {
   private:
    internal::value<Context> value_;
    internal::type type_;
  
    template <typename ContextType, typename T>
    friend FMT_CONSTEXPR basic_format_arg<ContextType>
      internal::make_arg(const T &value);
  
    template <typename Visitor, typename Ctx>
    friend FMT_CONSTEXPR typename internal::result_of<Visitor(int)>::type
      visit_format_arg(Visitor &&vis, const basic_format_arg<Ctx> &arg);
  
    friend class basic_format_args<Context>;
    friend class internal::arg_map<Context>;
  
    typedef typename Context::char_type char_type;
  
   public:
    class handle {
     public:
      explicit handle(internal::custom_value<Context> custom): custom_(custom) {}
  
      void format(Context &ctx) const { custom_.format(custom_.value, ctx); }
  
     private:
      internal::custom_value<Context> custom_;
    };
  
    FMT_CONSTEXPR basic_format_arg() : type_(internal::none_type) {}
  
    FMT_EXPLICIT operator bool() const FMT_NOEXCEPT {
      return type_ != internal::none_type;
    }
  
    internal::type type() const { return type_; }
  
    bool is_integral() const { return internal::is_integral(type_); }
    bool is_arithmetic() const { return internal::is_arithmetic(type_); }
  };
  
  struct monostate {};
  
  /**
    \rst
    Visits an argument dispatching to the appropriate visit method based on
    the argument type. For example, if the argument type is ``double`` then
    ``vis(value)`` will be called with the value of type ``double``.
    \endrst
   */
  template <typename Visitor, typename Context>
  FMT_CONSTEXPR typename internal::result_of<Visitor(int)>::type
      visit_format_arg(Visitor &&vis, const basic_format_arg<Context> &arg) {
    typedef typename Context::char_type char_type;
    switch (arg.type_) {
    case internal::none_type:
      break;
    case internal::named_arg_type:
      FMT_ASSERT(false, "invalid argument type");
      break;
    case internal::int_type:
      return vis(arg.value_.int_value);
    case internal::uint_type:
      return vis(arg.value_.uint_value);
    case internal::long_long_type:
      return vis(arg.value_.long_long_value);
    case internal::ulong_long_type:
      return vis(arg.value_.ulong_long_value);
    case internal::bool_type:
      return vis(arg.value_.int_value != 0);
    case internal::char_type:
      return vis(static_cast<char_type>(arg.value_.int_value));
    case internal::double_type:
      return vis(arg.value_.double_value);
    case internal::long_double_type:
      return vis(arg.value_.long_double_value);
    case internal::cstring_type:
      return vis(arg.value_.string.value);
    case internal::string_type:
      return vis(basic_string_view<char_type>(
                   arg.value_.string.value, arg.value_.string.size));
    case internal::pointer_type:
      return vis(arg.value_.pointer);
    case internal::custom_type:
      return vis(typename basic_format_arg<Context>::handle(arg.value_.custom));
    }
    return vis(monostate());
  }
  
  // DEPRECATED!
  template <typename Visitor, typename Context>
  FMT_CONSTEXPR typename internal::result_of<Visitor(int)>::type
      visit(Visitor &&vis, const basic_format_arg<Context> &arg) {
    return visit_format_arg(std::forward<Visitor>(vis), arg);
  }
  
  // Parsing context consisting of a format string range being parsed and an
  // argument counter for automatic indexing.
  template <typename Char, typename ErrorHandler = internal::error_handler>
  class basic_parse_context : private ErrorHandler {
   private:
    basic_string_view<Char> format_str_;
    int next_arg_id_;
  
   public:
    typedef Char char_type;
    typedef typename basic_string_view<Char>::iterator iterator;
  
    explicit FMT_CONSTEXPR basic_parse_context(
        basic_string_view<Char> format_str, ErrorHandler eh = ErrorHandler())
      : ErrorHandler(eh), format_str_(format_str), next_arg_id_(0) {}
  
    // Returns an iterator to the beginning of the format string range being
    // parsed.
    FMT_CONSTEXPR iterator begin() const FMT_NOEXCEPT {
      return format_str_.begin();
    }
  
    // Returns an iterator past the end of the format string range being parsed.
    FMT_CONSTEXPR iterator end() const FMT_NOEXCEPT { return format_str_.end(); }
  
    // Advances the begin iterator to ``it``.
    FMT_CONSTEXPR void advance_to(iterator it) {
      format_str_.remove_prefix(internal::to_unsigned(it - begin()));
    }
  
    // Returns the next argument index.
    FMT_CONSTEXPR unsigned next_arg_id();
  
    FMT_CONSTEXPR bool check_arg_id(unsigned) {
      if (next_arg_id_ > 0) {
        on_error("cannot switch from automatic to manual argument indexing");
        return false;
      }
      next_arg_id_ = -1;
      return true;
    }
    void check_arg_id(basic_string_view<Char>) {}
  
    FMT_CONSTEXPR void on_error(const char *message) {
      ErrorHandler::on_error(message);
    }
  
    FMT_CONSTEXPR ErrorHandler error_handler() const { return *this; }
  };
  
  typedef basic_parse_context<char> format_parse_context;
  typedef basic_parse_context<wchar_t> wformat_parse_context;
  
  // DEPRECATED!
  typedef basic_parse_context<char> parse_context;
  typedef basic_parse_context<wchar_t> wparse_context;
  
  namespace internal {
  // A map from argument names to their values for named arguments.
  template <typename Context>
  class arg_map {
   private:
    arg_map(const arg_map &) = delete;
    void operator=(const arg_map &) = delete;
  
    typedef typename Context::char_type char_type;
  
    struct entry {
      basic_string_view<char_type> name;
      basic_format_arg<Context> arg;
    };
  
    entry *map_;
    unsigned size_;
  
    void push_back(value<Context> val) {
      const internal::named_arg_base<char_type> &named = val.as_named_arg();
      map_[size_] = entry{named.name, named.template deserialize<Context>()};
      ++size_;
    }
  
   public:
    arg_map() : map_(FMT_NULL), size_(0) {}
    void init(const basic_format_args<Context> &args);
    ~arg_map() { delete [] map_; }
  
    basic_format_arg<Context> find(basic_string_view<char_type> name) const {
      // The list is unsorted, so just return the first matching name.
      for (entry *it = map_, *end = map_ + size_; it != end; ++it) {
        if (it->name == name)
          return it->arg;
      }
      return {};
    }
  };
  
  // A type-erased reference to an std::locale to avoid heavy <locale> include.
  class locale_ref {
   private:
    const void *locale_;  // A type-erased pointer to std::locale.
    friend class locale;
  
   public:
    locale_ref() : locale_(FMT_NULL) {}
  
    template <typename Locale>
    explicit locale_ref(const Locale &loc);
  
    template <typename Locale>
    Locale get() const;
  };
  
  template <typename OutputIt, typename Context, typename Char>
  class context_base {
   public:
    typedef OutputIt iterator;
  
   private:
    basic_parse_context<Char> parse_context_;
    iterator out_;
    basic_format_args<Context> args_;
    locale_ref loc_;
  
   protected:
    typedef Char char_type;
    typedef basic_format_arg<Context> format_arg;
  
    context_base(OutputIt out, basic_string_view<char_type> format_str,
                 basic_format_args<Context> ctx_args,
                 locale_ref loc = locale_ref())
    : parse_context_(format_str), out_(out), args_(ctx_args), loc_(loc) {}
  
    // Returns the argument with specified index.
    format_arg do_get_arg(unsigned arg_id) {
      format_arg arg = args_.get(arg_id);
      if (!arg)
        parse_context_.on_error("argument index out of range");
      return arg;
    }
  
    // Checks if manual indexing is used and returns the argument with
    // specified index.
    format_arg get_arg(unsigned arg_id) {
      return this->parse_context().check_arg_id(arg_id) ?
        this->do_get_arg(arg_id) : format_arg();
    }
  
   public:
    basic_parse_context<char_type> &parse_context() { return parse_context_; }
    basic_format_args<Context> args() const { return args_; } // DEPRECATED!
    basic_format_arg<Context> arg(unsigned id) const { return args_.get(id); }
  
    internal::error_handler error_handler() {
      return parse_context_.error_handler();
    }
  
    void on_error(const char *message) { parse_context_.on_error(message); }
  
    // Returns an iterator to the beginning of the output range.
    iterator out() { return out_; }
    iterator begin() { return out_; }  // deprecated
  
    // Advances the begin iterator to ``it``.
    void advance_to(iterator it) { out_ = it; }
  
    locale_ref locale() { return loc_; }
  };
  
  template <typename Context, typename T>
  struct get_type {
    typedef decltype(make_value<Context>(
          declval<typename std::decay<T>::type&>())) value_type;
    static const type value = value_type::type_tag;
  };
  
  template <typename Context>
  FMT_CONSTEXPR11 unsigned long long get_types() { return 0; }
  
  template <typename Context, typename Arg, typename... Args>
  FMT_CONSTEXPR11 unsigned long long get_types() {
    return get_type<Context, Arg>::value | (get_types<Context, Args...>() << 4);
  }
  
  template <typename Context, typename T>
  FMT_CONSTEXPR basic_format_arg<Context> make_arg(const T &value) {
    basic_format_arg<Context> arg;
    arg.type_ = get_type<Context, T>::value;
    arg.value_ = make_value<Context>(value);
    return arg;
  }
  
  template <bool IS_PACKED, typename Context, typename T>
  inline typename std::enable_if<IS_PACKED, value<Context>>::type
      make_arg(const T &value) {
    return make_value<Context>(value);
  }
  
  template <bool IS_PACKED, typename Context, typename T>
  inline typename std::enable_if<!IS_PACKED, basic_format_arg<Context>>::type
      make_arg(const T &value) {
    return make_arg<Context>(value);
  }
  }  // namespace internal
  
  // Formatting context.
  template <typename OutputIt, typename Char>
  class basic_format_context :
    public internal::context_base<
      OutputIt, basic_format_context<OutputIt, Char>, Char> {
   public:
    /** The character type for the output. */
    typedef Char char_type;
  
    // using formatter_type = formatter<T, char_type>;
    template <typename T>
    struct formatter_type { typedef formatter<T, char_type> type; };
  
   private:
    internal::arg_map<basic_format_context> map_;
  
    basic_format_context(const basic_format_context &) = delete;
    void operator=(const basic_format_context &) = delete;
  
    typedef internal::context_base<OutputIt, basic_format_context, Char> base;
    typedef typename base::format_arg format_arg;
    using base::get_arg;
  
   public:
    using typename base::iterator;
  
    /**
     Constructs a ``basic_format_context`` object. References to the arguments are
     stored in the object so make sure they have appropriate lifetimes.
     */
    basic_format_context(OutputIt out, basic_string_view<char_type> format_str,
                         basic_format_args<basic_format_context> ctx_args,
                         internal::locale_ref loc = internal::locale_ref())
      : base(out, format_str, ctx_args, loc) {}
  
    format_arg next_arg() {
      return this->do_get_arg(this->parse_context().next_arg_id());
    }
    format_arg get_arg(unsigned arg_id) { return this->do_get_arg(arg_id); }
  
    // Checks if manual indexing is used and returns the argument with the
    // specified name.
    format_arg get_arg(basic_string_view<char_type> name);
  };
  
  template <typename Char>
  struct buffer_context {
    typedef basic_format_context<
      std::back_insert_iterator<internal::basic_buffer<Char>>, Char> type;
  };
  typedef buffer_context<char>::type format_context;
  typedef buffer_context<wchar_t>::type wformat_context;
  
  /**
    \rst
    An array of references to arguments. It can be implicitly converted into
    `~fmt::basic_format_args` for passing into type-erased formatting functions
    such as `~fmt::vformat`.
    \endrst
   */
  template <typename Context, typename ...Args>
  class format_arg_store {
   private:
    static const size_t NUM_ARGS = sizeof...(Args);
  
    // Packed is a macro on MinGW so use IS_PACKED instead.
    static const bool IS_PACKED = NUM_ARGS < internal::max_packed_args;
  
    typedef typename std::conditional<IS_PACKED,
      internal::value<Context>, basic_format_arg<Context>>::type value_type;
  
    // If the arguments are not packed, add one more element to mark the end.
    static const size_t DATA_SIZE =
            NUM_ARGS + (IS_PACKED && NUM_ARGS != 0 ? 0 : 1);
    value_type data_[DATA_SIZE];
  
    friend class basic_format_args<Context>;
  
    static FMT_CONSTEXPR11 unsigned long long get_types() {
      return IS_PACKED ?
        internal::get_types<Context, Args...>() :
        internal::is_unpacked_bit | NUM_ARGS;
    }
  
   public:
  #if FMT_USE_CONSTEXPR11
    static FMT_CONSTEXPR11 unsigned long long TYPES = get_types();
  #else
    static const unsigned long long TYPES;
  #endif
  
  #if (FMT_GCC_VERSION && FMT_GCC_VERSION <= 405) || \
      (FMT_MSC_VER && FMT_MSC_VER <= 1800)
    // Workaround array initialization issues in gcc <= 4.5 and MSVC <= 2013.
    format_arg_store(const Args &... args) {
      value_type init[DATA_SIZE] =
        {internal::make_arg<IS_PACKED, Context>(args)...};
      std::memcpy(data_, init, sizeof(init));
    }
  #else
    format_arg_store(const Args &... args)
      : data_{internal::make_arg<IS_PACKED, Context>(args)...} {}
  #endif
  };
  
  #if !FMT_USE_CONSTEXPR11
  template <typename Context, typename ...Args>
  const unsigned long long format_arg_store<Context, Args...>::TYPES =
      get_types();
  #endif
  
  /**
    \rst
    Constructs an `~fmt::format_arg_store` object that contains references to
    arguments and can be implicitly converted to `~fmt::format_args`. `Context`
    can be omitted in which case it defaults to `~fmt::context`.
    \endrst
   */
  template <typename Context = format_context, typename ...Args>
  inline format_arg_store<Context, Args...>
    make_format_args(const Args &... args) { return {args...}; }
  
  /** Formatting arguments. */
  template <typename Context>
  class basic_format_args {
   public:
    typedef unsigned size_type;
    typedef basic_format_arg<Context>  format_arg;
  
   private:
    // To reduce compiled code size per formatting function call, types of first
    // max_packed_args arguments are passed in the types_ field.
    unsigned long long types_;
    union {
      // If the number of arguments is less than max_packed_args, the argument
      // values are stored in values_, otherwise they are stored in args_.
      // This is done to reduce compiled code size as storing larger objects
      // may require more code (at least on x86-64) even if the same amount of
      // data is actually copied to stack. It saves ~10% on the bloat test.
      const internal::value<Context> *values_;
      const format_arg *args_;
    };
  
    bool is_packed() const { return (types_ & internal::is_unpacked_bit) == 0; }
  
    typename internal::type type(unsigned index) const {
      unsigned shift = index * 4;
      return static_cast<typename internal::type>(
        (types_ & (0xfull << shift)) >> shift);
    }
  
    friend class internal::arg_map<Context>;
  
    void set_data(const internal::value<Context> *values) { values_ = values; }
    void set_data(const format_arg *args) { args_ = args; }
  
    format_arg do_get(size_type index) const {
      format_arg arg;
      if (!is_packed()) {
        auto num_args = max_size();
        if (index < num_args)
          arg = args_[index];
        return arg;
      }
      if (index > internal::max_packed_args)
        return arg;
      arg.type_ = type(index);
      if (arg.type_ == internal::none_type)
        return arg;
      internal::value<Context> &val = arg.value_;
      val = values_[index];
      return arg;
    }
  
   public:
    basic_format_args() : types_(0) {}
  
    /**
     \rst
     Constructs a `basic_format_args` object from `~fmt::format_arg_store`.
     \endrst
     */
    template <typename... Args>
    basic_format_args(const format_arg_store<Context, Args...> &store)
    : types_(static_cast<unsigned long long>(store.TYPES)) {
      set_data(store.data_);
    }
  
    /**
     \rst
     Constructs a `basic_format_args` object from a dynamic set of arguments.
     \endrst
     */
    basic_format_args(const format_arg *args, size_type count)
      : types_(internal::is_unpacked_bit | count) {
      set_data(args);
    }
  
    /** Returns the argument at specified index. */
    format_arg get(size_type index) const {
      format_arg arg = do_get(index);
      if (arg.type_ == internal::named_arg_type)
        arg = arg.value_.as_named_arg().template deserialize<Context>();
      return arg;
    }
  
    size_type max_size() const {
      unsigned long long max_packed = internal::max_packed_args;
      return static_cast<size_type>(
        is_packed() ? max_packed : types_ & ~internal::is_unpacked_bit);
    }
  };
  
  /** An alias to ``basic_format_args<context>``. */
  // It is a separate type rather than a typedef to make symbols readable.
  struct format_args : basic_format_args<format_context> {
    template <typename ...Args>
    format_args(Args &&... arg)
    : basic_format_args<format_context>(std::forward<Args>(arg)...) {}
  };
  struct wformat_args : basic_format_args<wformat_context> {
    template <typename ...Args>
    wformat_args(Args &&... arg)
    : basic_format_args<wformat_context>(std::forward<Args>(arg)...) {}
  };
  
  #define FMT_ENABLE_IF_T(B, T) typename std::enable_if<B, T>::type
  
  #ifndef FMT_USE_ALIAS_TEMPLATES
  # define FMT_USE_ALIAS_TEMPLATES FMT_HAS_FEATURE(cxx_alias_templates)
  #endif
  #if FMT_USE_ALIAS_TEMPLATES
  /** String's character type. */
  template <typename S>
  using char_t = FMT_ENABLE_IF_T(
    internal::is_string<S>::value, typename internal::char_t<S>::type);
  #define FMT_CHAR(S) fmt::char_t<S>
  #else
  template <typename S>
  struct char_t : std::enable_if<
      internal::is_string<S>::value, typename internal::char_t<S>::type> {};
  #define FMT_CHAR(S) typename char_t<S>::type
  #endif
  
  namespace internal {
  template <typename Char>
  struct named_arg_base {
    basic_string_view<Char> name;
  
    // Serialized value<context>.
    mutable char data[
      sizeof(basic_format_arg<typename buffer_context<Char>::type>)];
  
    named_arg_base(basic_string_view<Char> nm) : name(nm) {}
  
    template <typename Context>
    basic_format_arg<Context> deserialize() const {
      basic_format_arg<Context> arg;
      std::memcpy(&arg, data, sizeof(basic_format_arg<Context>));
      return arg;
    }
  };
  
  template <typename T, typename Char>
  struct named_arg : named_arg_base<Char> {
    const T &value;
  
    named_arg(basic_string_view<Char> name, const T &val)
      : named_arg_base<Char>(name), value(val) {}
  };
  
  template <typename... Args, typename S>
  inline typename std::enable_if<!is_compile_string<S>::value>::type
    check_format_string(const S &) {}
  template <typename... Args, typename S>
  typename std::enable_if<is_compile_string<S>::value>::type
    check_format_string(S);
  
  template <typename S, typename... Args>
  struct checked_args : format_arg_store<
    typename buffer_context<FMT_CHAR(S)>::type, Args...> {
    typedef typename buffer_context<FMT_CHAR(S)>::type context;
  
    checked_args(const S &format_str, const Args &... args):
      format_arg_store<context, Args...>(args...) {
      internal::check_format_string<Args...>(format_str);
    }
  
    basic_format_args<context> operator*() const { return *this; }
  };
  
  template <typename Char>
  std::basic_string<Char> vformat(
    basic_string_view<Char> format_str,
    basic_format_args<typename buffer_context<Char>::type> args);
  
  template <typename Char>
  typename buffer_context<Char>::type::iterator vformat_to(
    internal::basic_buffer<Char> &buf, basic_string_view<Char> format_str,
    basic_format_args<typename buffer_context<Char>::type> args);
  }
  
  /**
    \rst
    Returns a named argument to be used in a formatting function.
  
    **Example**::
  
      fmt::print("Elapsed time: {s:.2f} seconds", fmt::arg("s", 1.23));
    \endrst
   */
  template <typename T>
  inline internal::named_arg<T, char> arg(string_view name, const T &arg) {
    return {name, arg};
  }
  
  template <typename T>
  inline internal::named_arg<T, wchar_t> arg(wstring_view name, const T &arg) {
    return {name, arg};
  }
  
  // Disable nested named arguments, e.g. ``arg("a", arg("b", 42))``.
  template <typename S, typename T, typename Char>
  void arg(S, internal::named_arg<T, Char>) = delete;
  
  template <typename Container>
  struct is_contiguous: std::false_type {};
  
  template <typename Char>
  struct is_contiguous<std::basic_string<Char> >: std::true_type {};
  
  template <typename Char>
  struct is_contiguous<internal::basic_buffer<Char> >: std::true_type {};
  
  /** Formats a string and writes the output to ``out``. */
  template <typename Container, typename S>
  typename std::enable_if<
      is_contiguous<Container>::value, std::back_insert_iterator<Container>>::type
    vformat_to(
      std::back_insert_iterator<Container> out,
      const S &format_str,
      basic_format_args<typename buffer_context<FMT_CHAR(S)>::type> args) {
    internal::container_buffer<Container> buf(internal::get_container(out));
    internal::vformat_to(buf, to_string_view(format_str), args);
    return out;
  }
  
  template <typename Container, typename S, typename... Args>
  inline typename std::enable_if<
    is_contiguous<Container>::value && internal::is_string<S>::value,
    std::back_insert_iterator<Container>>::type
      format_to(std::back_insert_iterator<Container> out, const S &format_str,
                const Args &... args) {
    internal::checked_args<S, Args...> ca(format_str, args...);
    return vformat_to(out, to_string_view(format_str), *ca);
  }
  
  template <typename S, typename Char = FMT_CHAR(S)>
  inline std::basic_string<Char> vformat(
      const S &format_str,
      basic_format_args<typename buffer_context<Char>::type> args) {
    return internal::vformat(to_string_view(format_str), args);
  }
  
  /**
    \rst
    Formats arguments and returns the result as a string.
  
    **Example**::
  
      #include <fmt/core.h>
      std::string message = fmt::format("The answer is {}", 42);
    \endrst
  */
  template <typename S, typename... Args>
  inline std::basic_string<FMT_CHAR(S)> format(
      const S &format_str, const Args &... args) {
    return internal::vformat(
      to_string_view(format_str),
      *internal::checked_args<S, Args...>(format_str, args...));
  }
  
  FMT_API void vprint(std::FILE *f, string_view format_str, format_args args);
  FMT_API void vprint(std::FILE *f, wstring_view format_str, wformat_args args);
  
  /**
    \rst
    Prints formatted data to the file *f*. For wide format strings,
    *f* should be in wide-oriented mode set via ``fwide(f, 1)`` or
    ``_setmode(_fileno(f), _O_U8TEXT)`` on Windows.
  
    **Example**::
  
      fmt::print(stderr, "Don't {}!", "panic");
    \endrst
   */
  template <typename S, typename... Args>
  inline FMT_ENABLE_IF_T(internal::is_string<S>::value, void)
      print(std::FILE *f, const S &format_str, const Args &... args) {
    vprint(f, to_string_view(format_str),
           internal::checked_args<S, Args...>(format_str, args...));
  }
  
  FMT_API void vprint(string_view format_str, format_args args);
  FMT_API void vprint(wstring_view format_str, wformat_args args);
  
  /**
    \rst
    Prints formatted data to ``stdout``.
  
    **Example**::
  
      fmt::print("Elapsed time: {0:.2f} seconds", 1.23);
    \endrst
   */
  template <typename S, typename... Args>
  inline FMT_ENABLE_IF_T(internal::is_string<S>::value, void)
      print(const S &format_str, const Args &... args) {
    vprint(to_string_view(format_str),
           internal::checked_args<S, Args...>(format_str, args...));
  }
  FMT_END_NAMESPACE
  
  #endif  // FMT_CORE_H_
  