xchar.h

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// Formatting library for C++ - optional wchar_t and exotic character support
//
// Copyright (c) 2012 - present, Victor Zverovich
// All rights reserved.
//
// For the license information refer to format.h.
 
#ifndef FMT_XCHAR_H_
#define FMT_XCHAR_H_
 
#include <cwchar>
 
#include "format.h"
 
FMT_BEGIN_NAMESPACE
namespace detail
{
    template <typename T>
    using is_exotic_char = bool_constant<!std::is_same<T, char>::value>;
}
 
FMT_MODULE_EXPORT_BEGIN
 
using wstring_view          = basic_string_view<wchar_t>;
using wformat_parse_context = basic_format_parse_context<wchar_t>;
using wformat_context       = buffer_context<wchar_t>;
using wformat_args          = basic_format_args<wformat_context>;
using wmemory_buffer        = basic_memory_buffer<wchar_t>;
 
#if FMT_GCC_VERSION && FMT_GCC_VERSION < 409
// Workaround broken conversion on older gcc.
template <typename... Args>
using wformat_string = wstring_view;
inline auto runtime(wstring_view s) -> wstring_view
{
    return s;
}
#else
template <typename... Args>
using wformat_string = basic_format_string<wchar_t, type_identity_t<Args>...>;
inline auto runtime(wstring_view s) -> basic_runtime<wchar_t>
{
    return {{s}};
}
#endif
 
template <>
struct is_char<wchar_t> : std::true_type
{
};
template <>
struct is_char<detail::char8_type> : std::true_type
{
};
template <>
struct is_char<char16_t> : std::true_type
{
};
template <>
struct is_char<char32_t> : std::true_type
{
};
 
template <typename... Args>
constexpr format_arg_store<wformat_context, Args...> make_wformat_args(
    const Args&... args)
{
    return {args...};
}
 
inline namespace literals
{
#if FMT_USE_USER_DEFINED_LITERALS && !FMT_USE_NONTYPE_TEMPLATE_ARGS
    constexpr detail::udl_arg<wchar_t> operator"" _a(const wchar_t * s, size_t)
    {
        return {s};
    }
#endif
} // namespace literals
 
template <typename It, typename Sentinel>
auto join(It begin, Sentinel end, wstring_view sep)
    -> join_view<It, Sentinel, wchar_t>
{
    return {begin, end, sep};
}
 
template <typename Range>
auto join(Range&& range, wstring_view sep)
    -> join_view<detail::iterator_t<Range>, detail::sentinel_t<Range>, wchar_t>
{
    return join(std::begin(range), std::end(range), sep);
}
 
template <typename T>
auto join(std::initializer_list<T> list, wstring_view sep)
    -> join_view<const T*, const T*, wchar_t>
{
    return join(std::begin(list), std::end(list), sep);
}
 
template <typename Char, FMT_ENABLE_IF(!std::is_same<Char, char>::value)>
auto vformat(basic_string_view<Char>                                  format_str,
             basic_format_args<buffer_context<type_identity_t<Char>>> args)
    -> std::basic_string<Char>
{
    basic_memory_buffer<Char> buffer;
    detail::vformat_to(buffer, format_str, args);
    return to_string(buffer);
}
 
template <typename... T>
auto format(wformat_string<T...> fmt, T&&... args) -> std::wstring
{
    return vformat(fmt::wstring_view(fmt), fmt::make_wformat_args(args...));
}
 
// Pass char_t as a default template parameter instead of using
// std::basic_string<char_t<S>> to reduce the symbol size.
template <typename S, typename... Args, typename Char = char_t<S>, FMT_ENABLE_IF(!std::is_same<Char, char>::value && !std::is_same<Char, wchar_t>::value)>
auto format(const S& format_str, Args&&... args) -> std::basic_string<Char>
{
    return vformat(detail::to_string_view(format_str),
                   fmt::make_format_args<buffer_context<Char>>(args...));
}
 
template <typename Locale, typename S, typename Char = char_t<S>, FMT_ENABLE_IF(detail::is_locale<Locale>::value&& detail::is_exotic_char<Char>::value)>
inline auto vformat(
    const Locale& loc, const S& format_str, basic_format_args<buffer_context<type_identity_t<Char>>> args)
    -> std::basic_string<Char>
{
    return detail::vformat(loc, detail::to_string_view(format_str), args);
}
 
template <typename Locale, typename S, typename... Args, typename Char = char_t<S>, FMT_ENABLE_IF(detail::is_locale<Locale>::value&& detail::is_exotic_char<Char>::value)>
inline auto format(const Locale& loc, const S& format_str, Args&&... args)
    -> std::basic_string<Char>
{
    return detail::vformat(loc, detail::to_string_view(format_str),
                           fmt::make_format_args<buffer_context<Char>>(args...));
}
 
template <typename OutputIt, typename S, typename Char = char_t<S>, FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&& detail::is_exotic_char<Char>::value)>
auto vformat_to(OutputIt out, const S& format_str, basic_format_args<buffer_context<type_identity_t<Char>>> args)
    -> OutputIt
{
    auto&& buf = detail::get_buffer<Char>(out);
    detail::vformat_to(buf, detail::to_string_view(format_str), args);
    return detail::get_iterator(buf);
}
 
template <typename OutputIt, typename S, typename... Args, typename Char = char_t<S>, FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&& detail::is_exotic_char<Char>::value)>
inline auto format_to(OutputIt out, const S& fmt, Args&&... args) -> OutputIt
{
    return vformat_to(out, detail::to_string_view(fmt),
                      fmt::make_format_args<buffer_context<Char>>(args...));
}
 
template <typename Locale, typename S, typename OutputIt, typename... Args, typename Char = char_t<S>, FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&& detail::is_locale<Locale>::value&& detail::is_exotic_char<Char>::value)>
inline auto vformat_to(
    OutputIt out, const Locale& loc, const S& format_str, basic_format_args<buffer_context<type_identity_t<Char>>> args) -> OutputIt
{
    auto&& buf = detail::get_buffer<Char>(out);
    vformat_to(buf, detail::to_string_view(format_str), args,
               detail::locale_ref(loc));
    return detail::get_iterator(buf);
}
 
template <
    typename OutputIt,
    typename Locale,
    typename S,
    typename... Args,
    typename Char = char_t<S>,
    bool enable   = detail::is_output_iterator<OutputIt, Char>::value &&
                  detail::is_locale<Locale>::value && detail::is_exotic_char<Char>::value>
inline auto format_to(OutputIt out, const Locale& loc, const S& format_str, Args&&... args) ->
    typename std::enable_if<enable, OutputIt>::type
{
    return vformat_to(out, loc, to_string_view(format_str),
                      fmt::make_format_args<buffer_context<Char>>(args...));
}
 
template <typename OutputIt, typename Char, typename... Args, FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&& detail::is_exotic_char<Char>::value)>
inline auto vformat_to_n(
    OutputIt out, size_t n, basic_string_view<Char> format_str, basic_format_args<buffer_context<type_identity_t<Char>>> args)
    -> format_to_n_result<OutputIt>
{
    detail::iterator_buffer<OutputIt, Char, detail::fixed_buffer_traits> buf(out,
                                                                             n);
    detail::vformat_to(buf, format_str, args);
    return {buf.out(), buf.count()};
}
 
template <typename OutputIt, typename S, typename... Args, typename Char = char_t<S>, FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&& detail::is_exotic_char<Char>::value)>
inline auto format_to_n(OutputIt out, size_t n, const S& fmt, const Args&... args) -> format_to_n_result<OutputIt>
{
    return vformat_to_n(out, n, detail::to_string_view(fmt),
                        fmt::make_format_args<buffer_context<Char>>(args...));
}
 
template <typename S, typename... Args, typename Char = char_t<S>, FMT_ENABLE_IF(detail::is_exotic_char<Char>::value)>
inline auto formatted_size(const S& fmt, Args&&... args) -> size_t
{
    detail::counting_buffer<Char> buf;
    detail::vformat_to(buf, detail::to_string_view(fmt),
                       fmt::make_format_args<buffer_context<Char>>(args...));
    return buf.count();
}
 
inline void vprint(std::FILE* f, wstring_view fmt, wformat_args args)
{
    wmemory_buffer buffer;
    detail::vformat_to(buffer, fmt, args);
    buffer.push_back(L'\0');
    if (std::fputws(buffer.data(), f) == -1)
        FMT_THROW(system_error(errno, FMT_STRING("cannot write to file")));
}
 
inline void vprint(wstring_view fmt, wformat_args args)
{
    vprint(stdout, fmt, args);
}
 
template <typename... T>
void print(std::FILE* f, wformat_string<T...> fmt, T&&... args)
{
    return vprint(f, wstring_view(fmt), fmt::make_wformat_args(args...));
}
 
template <typename... T>
void print(wformat_string<T...> fmt, T&&... args)
{
    return vprint(wstring_view(fmt), fmt::make_wformat_args(args...));
}
 
template <typename T>
inline auto to_wstring(const T& value) -> std::wstring
{
    return format(FMT_STRING(L"{}"), value);
}
FMT_MODULE_EXPORT_END
FMT_END_NAMESPACE
 
#endif // FMT_XCHAR_H_