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|
// 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 50301
#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_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
// 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
// [[noreturn]] is disabled on MSVC because of bogus unreachable code warnings.
#if FMT_EXCEPTIONS && FMT_HAS_CPP_ATTRIBUTE(noreturn) && !FMT_MSC_VER
# define FMT_NORETURN [[noreturn]]
#else
# define FMT_NORETURN
#endif
#ifndef FMT_DEPRECATED
# if (FMT_HAS_CPP_ATTRIBUTE(deprecated) && __cplusplus >= 201402L) || \
FMT_MSC_VER >= 1900
# define FMT_DEPRECATED [[deprecated]]
# else
# if defined(__GNUC__) || defined(__clang__)
# define FMT_DEPRECATED __attribute__((deprecated))
# elif FMT_MSC_VER
# define FMT_DEPRECATED __declspec(deprecated)
# else
# define FMT_DEPRECATED /* deprecated */
# endif
# 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)
# define FMT_EXTERN_TEMPLATE_API FMT_API
# endif
#endif
#ifndef FMT_API
# define FMT_API
#endif
#ifndef FMT_EXTERN_TEMPLATE_API
# define FMT_EXTERN_TEMPLATE_API
#endif
#ifndef FMT_HEADER_ONLY
# define FMT_EXTERN extern
#else
# define FMT_EXTERN
#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_USE_STRING_VIEW
#elif FMT_HAS_INCLUDE("experimental/string_view") && __cplusplus >= 201402L
# include <experimental/string_view>
# define FMT_USE_EXPERIMENTAL_STRING_VIEW
#endif
FMT_BEGIN_NAMESPACE
// Implementations of enable_if_t and other types for pre-C++14 systems.
template <bool B, class T = void>
using enable_if_t = typename std::enable_if<B, T>::type;
template <bool B, class T, class F>
using conditional_t = typename std::conditional<B, T, F>::type;
template <bool B> using bool_constant = std::integral_constant<bool, B>;
template <typename T>
using remove_reference_t = typename std::remove_reference<T>::type;
struct monostate {};
// An enable_if helper to be used in template parameters which results in much
// shorter symbols: https://godbolt.org/z/sWw4vP. Extra parentheses are needed
// to workaround a bug in MSVC 2019 (see #1140 and #1186).
#define FMT_ENABLE_IF(...) enable_if_t<(__VA_ARGS__), int> = 0
namespace internal {
#if defined(FMT_USE_STRING_VIEW)
template <typename Char> using std_string_view = std::basic_string_view<Char>;
#elif defined(FMT_USE_EXPERIMENTAL_STRING_VIEW)
template <typename Char>
using std_string_view = std::experimental::basic_string_view<Char>;
#else
template <typename T> struct std_string_view {};
#endif
// 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);
}
} // namespace internal
/**
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:
using char_type = Char;
using iterator = const Char*;
FMT_CONSTEXPR basic_string_view() FMT_NOEXCEPT : data_(nullptr), 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()) {}
template <
typename S,
FMT_ENABLE_IF(std::is_same<S, internal::std_string_view<Char>>::value)>
FMT_CONSTEXPR basic_string_view(S s) FMT_NOEXCEPT : data_(s.data()),
size_(s.size()) {}
/** 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;
}
};
using string_view = basic_string_view<char>;
using wstring_view = basic_string_view<wchar_t>;
#ifndef __cpp_char8_t
// A UTF-8 code unit type.
enum char8_t : unsigned char {};
#endif
/** Specifies if ``T`` is a character type. Can be specialized by users. */
template <typename T> struct is_char : std::false_type {};
template <> struct is_char<char> : std::true_type {};
template <> struct is_char<wchar_t> : std::true_type {};
template <> struct is_char<char8_t> : std::true_type {};
template <> struct is_char<char16_t> : std::true_type {};
template <> struct is_char<char32_t> : std::true_type {};
/**
\rst
Returns a string view of `s`. In order to add custom string type support to
{fmt} provide an overload of `to_string_view` for it in the same namespace as
the type for the argument-dependent lookup to work.
**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, FMT_ENABLE_IF(is_char<Char>::value)>
inline basic_string_view<Char> to_string_view(const Char* s) {
return s;
}
template <typename Char, typename Traits, typename Allocator>
inline basic_string_view<Char> to_string_view(
const std::basic_string<Char, Traits, Allocator>& s) {
return {s.data(), s.size()};
}
template <typename Char>
inline basic_string_view<Char> to_string_view(basic_string_view<Char> s) {
return s;
}
template <typename Char,
FMT_ENABLE_IF(!std::is_empty<internal::std_string_view<Char>>::value)>
inline basic_string_view<Char> to_string_view(
internal::std_string_view<Char> s) {
return s;
}
// 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, FMT_ENABLE_IF(is_compile_string<S>::value)>
constexpr basic_string_view<typename S::char_type> to_string_view(const S& s) {
return s;
}
namespace internal {
void to_string_view(...);
using fmt::v5::to_string_view;
// Specifies whether S is a string type convertible to fmt::basic_string_view.
// It should be a constexpr function but MSVC 2017 fails to compile it in
// enable_if and MSVC 2015 fails to compile it as an alias template.
template <typename S>
struct is_string : std::is_class<decltype(to_string_view(std::declval<S>()))> {
};
template <typename S, typename = void> struct char_t_impl {};
template <typename S> struct char_t_impl<S, enable_if_t<is_string<S>::value>> {
using result = decltype(to_string_view(std::declval<S>()));
using type = typename result::char_type;
};
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_NORETURN FMT_API void on_error(const char* message);
};
} // namespace internal
/** String's character type. */
template <typename S> using char_t = typename internal::char_t_impl<S>::type;
// 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:
using char_type = Char;
using iterator = typename basic_string_view<Char>::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() {
if (next_arg_id_ >= 0) return internal::to_unsigned(next_arg_id_++);
on_error("cannot switch from manual to automatic argument indexing");
return 0;
}
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;
}
FMT_CONSTEXPR 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; }
};
using format_parse_context = basic_parse_context<char>;
using wformat_parse_context = basic_parse_context<wchar_t>;
using parse_context FMT_DEPRECATED = basic_parse_context<char>;
using wparse_context FMT_DEPRECATED = basic_parse_context<wchar_t>;
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 {
// A deleted default constructor indicates a disabled formatter.
formatter() = delete;
};
template <typename T, typename Char, typename Enable = void>
struct FMT_DEPRECATED convert_to_int
: bool_constant<!std::is_arithmetic<T>::value &&
std::is_convertible<T, int>::value> {};
namespace internal {
// Specifies if T has an enabled formatter specialization. A type can be
// formattable even if it doesn't have a formatter e.g. via a conversion.
template <typename T, typename Context>
using has_formatter =
std::is_constructible<typename Context::template formatter_type<T>>;
/** A contiguous memory buffer with an optional growing ability. */
template <typename T> class buffer {
private:
buffer(const buffer&) = delete;
void operator=(const 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.
buffer(std::size_t sz) FMT_NOEXCEPT : size_(sz), capacity_(sz) {}
buffer(T* p = nullptr, 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:
using value_type = T;
using const_reference = const T&;
virtual ~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]; }
};
// A container-backed buffer.
template <typename Container>
class container_buffer : public 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)
: 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) {
using bi_iterator = std::back_insert_iterator<Container>;
struct accessor : bi_iterator {
accessor(bi_iterator iter) : bi_iterator(iter) {}
using bi_iterator::container;
};
return *accessor(it).container;
}
template <typename T, typename Char = char, typename Enable = void>
struct fallback_formatter {
fallback_formatter() = delete;
};
// Specifies if T has an enabled fallback_formatter specialization.
template <typename T, typename Context>
using has_fallback_formatter =
std::is_constructible<fallback_formatter<T, typename Context::char_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
};
// Maps core type T to the corresponding type enum constant.
template <typename T, typename Char>
struct type_constant : std::integral_constant<type, custom_type> {};
#define FMT_TYPE_CONSTANT(Type, constant) \
template <typename Char> \
struct type_constant<Type, Char> : std::integral_constant<type, constant> {}
FMT_TYPE_CONSTANT(const named_arg_base<Char>&, named_arg_type);
FMT_TYPE_CONSTANT(int, int_type);
FMT_TYPE_CONSTANT(unsigned, uint_type);
FMT_TYPE_CONSTANT(long long, long_long_type);
FMT_TYPE_CONSTANT(unsigned long long, ulong_long_type);
FMT_TYPE_CONSTANT(bool, bool_type);
FMT_TYPE_CONSTANT(Char, char_type);
FMT_TYPE_CONSTANT(double, double_type);
FMT_TYPE_CONSTANT(long double, long_double_type);
FMT_TYPE_CONSTANT(const Char*, cstring_type);
FMT_TYPE_CONSTANT(basic_string_view<Char>, string_type);
FMT_TYPE_CONSTANT(const void*, pointer_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* data;
std::size_t size;
};
template <typename Context> struct custom_value {
using parse_context = basic_parse_context<typename Context::char_type>;
const void* value;
void (*format)(const void* arg, parse_context& parse_ctx, Context& ctx);
};
// A formatting argument value.
template <typename Context> class value {
public:
using char_type = typename Context::char_type;
union {
int int_value;
unsigned uint_value;
long long long_long_value;
unsigned long long ulong_long_value;
bool bool_value;
char_type char_value;
double double_value;
long double long_double_value;
const void* pointer;
string_value<char_type> string;
custom_value<Context> custom;
const named_arg_base<char_type>* named_arg;
};
FMT_CONSTEXPR value(int val = 0) : int_value(val) {}
FMT_CONSTEXPR 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(bool val) : bool_value(val) {}
value(char_type val) : char_value(val) {}
value(const char_type* val) { string.data = val; }
value(basic_string_view<char_type> val) {
string.data = val.data();
string.size = val.size();
}
value(const void* val) : pointer(val) {}
template <typename T> value(const T& val) {
custom.value = &val;
// 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`.
custom.format = format_custom_arg<
T, conditional_t<has_formatter<T, Context>::value,
typename Context::template formatter_type<T>,
fallback_formatter<T, char_type>>>;
}
value(const named_arg_base<char_type>& val) { named_arg = &val; }
private:
// Formats an argument of a custom type, such as a user-defined class.
template <typename T, typename Formatter>
static void format_custom_arg(const void* arg,
basic_parse_context<char_type>& parse_ctx,
Context& ctx) {
Formatter f;
parse_ctx.advance_to(f.parse(parse_ctx));
ctx.advance_to(f.format(*static_cast<const T*>(arg), ctx));
}
};
template <typename Context, typename T>
FMT_CONSTEXPR basic_format_arg<Context> make_arg(const T& value);
// 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.
enum { long_short = sizeof(long) == sizeof(int) };
using long_type = conditional_t<long_short, int, long long>;
using ulong_type = conditional_t<long_short, unsigned, unsigned long long>;
// Maps formatting arguments to core types.
template <typename Context> struct arg_mapper {
using char_type = typename Context::char_type;
FMT_CONSTEXPR int map(signed char val) { return val; }
FMT_CONSTEXPR unsigned map(unsigned char val) { return val; }
FMT_CONSTEXPR int map(short val) { return val; }
FMT_CONSTEXPR unsigned map(unsigned short val) { return val; }
FMT_CONSTEXPR int map(int val) { return val; }
FMT_CONSTEXPR unsigned map(unsigned val) { return val; }
FMT_CONSTEXPR long_type map(long val) { return val; }
FMT_CONSTEXPR ulong_type map(unsigned long val) { return val; }
FMT_CONSTEXPR long long map(long long val) { return val; }
FMT_CONSTEXPR unsigned long long map(unsigned long long val) { return val; }
FMT_CONSTEXPR bool map(bool val) { return val; }
template <typename T, FMT_ENABLE_IF(is_char<T>::value)>
FMT_CONSTEXPR char_type map(T val) {
static_assert(
std::is_same<T, char>::value || std::is_same<T, char_type>::value,
"mixing character types is disallowed");
return val;
}
FMT_CONSTEXPR double map(float val) { return static_cast<double>(val); }
FMT_CONSTEXPR double map(double val) { return val; }
FMT_CONSTEXPR long double map(long double val) { return val; }
FMT_CONSTEXPR const char_type* map(char_type* val) { return val; }
FMT_CONSTEXPR const char_type* map(const char_type* val) { return val; }
template <typename T, FMT_ENABLE_IF(is_string<T>::value)>
FMT_CONSTEXPR basic_string_view<char_type> map(const T& val) {
static_assert(std::is_same<char_type, char_t<T>>::value,
"mixing character types is disallowed");
return to_string_view(val);
}
template <typename T,
FMT_ENABLE_IF(
std::is_constructible<basic_string_view<char_type>, T>::value &&
!is_string<T>::value)>
FMT_CONSTEXPR basic_string_view<char_type> map(const T& val) {
return basic_string_view<char_type>(val);
}
FMT_CONSTEXPR const char* map(const signed char* val) {
static_assert(std::is_same<char_type, char>::value, "invalid string type");
return reinterpret_cast<const char*>(val);
}
FMT_CONSTEXPR const char* map(const unsigned char* val) {
static_assert(std::is_same<char_type, char>::value, "invalid string type");
return reinterpret_cast<const char*>(val);
}
FMT_CONSTEXPR const void* map(void* val) { return val; }
FMT_CONSTEXPR const void* map(const void* val) { return val; }
FMT_CONSTEXPR const void* map(std::nullptr_t val) { return val; }
template <typename T> FMT_CONSTEXPR int map(const T*) {
// 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.
static_assert(!sizeof(T), "formatting of non-void pointers is disallowed");
return 0;
}
template <typename T,
FMT_ENABLE_IF(std::is_enum<T>::value &&
!has_formatter<T, Context>::value &&
!has_fallback_formatter<T, Context>::value)>
FMT_CONSTEXPR int map(const T& val) {
return static_cast<int>(val);
}
template <typename T,
FMT_ENABLE_IF(!is_string<T>::value && !is_char<T>::value &&
(has_formatter<T, Context>::value ||
has_fallback_formatter<T, Context>::value))>
FMT_CONSTEXPR const T& map(const T& val) {
return val;
}
template <typename T>
FMT_CONSTEXPR const named_arg_base<char_type>& map(
const named_arg<T, char_type>& val) {
auto arg = make_arg<Context>(val.value);
std::memcpy(val.data, &arg, sizeof(arg));
return val;
}
};
// A type constant after applying arg_mapper<Context>.
template <typename T, typename Context>
using mapped_type_constant =
type_constant<decltype(arg_mapper<Context>().map(std::declval<T>())),
typename Context::char_type>;
// 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 auto visit_format_arg(Visitor&& vis,
const basic_format_arg<Ctx>& arg)
-> decltype(vis(0));
friend class basic_format_args<Context>;
friend class internal::arg_map<Context>;
using char_type = typename Context::char_type;
public:
class handle {
public:
explicit handle(internal::custom_value<Context> custom) : custom_(custom) {}
void format(basic_parse_context<char_type>& parse_ctx, Context& ctx) const {
custom_.format(custom_.value, parse_ctx, ctx);
}
private:
internal::custom_value<Context> custom_;
};
FMT_CONSTEXPR basic_format_arg() : type_(internal::none_type) {}
FMT_CONSTEXPR 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_); }
};
/**
\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 auto visit_format_arg(Visitor&& vis,
const basic_format_arg<Context>& arg)
-> decltype(vis(0)) {
using char_type = typename Context::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_.bool_value);
case internal::char_type:
return vis(arg.value_.char_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.data);
case internal::string_type:
return vis(basic_string_view<char_type>(arg.value_.string.data,
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());
}
template <typename Visitor, typename Context>
FMT_DEPRECATED FMT_CONSTEXPR auto visit(Visitor&& vis,
const basic_format_arg<Context>& arg)
-> decltype(vis(0)) {
return visit_format_arg(std::forward<Visitor>(vis), arg);
}
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;
using char_type = typename Context::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 auto& named = *val.named_arg;
map_[size_] = {named.name, named.template deserialize<Context>()};
++size_;
}
public:
arg_map() : map_(nullptr), 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.
public:
locale_ref() : locale_(nullptr) {}
template <typename Locale> explicit locale_ref(const Locale& loc);
template <typename Locale> Locale get() const;
};
template <typename> constexpr unsigned long long encode_types() { return 0; }
template <typename Context, typename Arg, typename... Args>
constexpr unsigned long long encode_types() {
return mapped_type_constant<Arg, Context>::value |
(encode_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_ = mapped_type_constant<T, Context>::value;
arg.value_ = arg_mapper<Context>().map(value);
return arg;
}
template <bool IS_PACKED, typename Context, typename T,
FMT_ENABLE_IF(IS_PACKED)>
inline value<Context> make_arg(const T& val) {
return arg_mapper<Context>().map(val);
}
template <bool IS_PACKED, typename Context, typename T,
FMT_ENABLE_IF(!IS_PACKED)>
inline basic_format_arg<Context> make_arg(const T& value) {
return make_arg<Context>(value);
}
} // namespace internal
// Formatting context.
template <typename OutputIt, typename Char> class basic_format_context {
public:
/** The character type for the output. */
using char_type = Char;
private:
OutputIt out_;
basic_format_args<basic_format_context> args_;
internal::arg_map<basic_format_context> map_;
internal::locale_ref loc_;
basic_format_context(const basic_format_context&) = delete;
void operator=(const basic_format_context&) = delete;
public:
using iterator = OutputIt;
using format_arg = basic_format_arg<basic_format_context>;
template <typename T> using formatter_type = formatter<T, char_type>;
/**
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_format_args<basic_format_context> ctx_args,
internal::locale_ref loc = internal::locale_ref())
: out_(out), args_(ctx_args), loc_(loc) {}
format_arg arg(unsigned id) const { return args_.get(id); }
// Checks if manual indexing is used and returns the argument with the
// specified name.
format_arg arg(basic_string_view<char_type> name);
internal::error_handler error_handler() { return {}; }
void on_error(const char* message) { error_handler().on_error(message); }
// Returns an iterator to the beginning of the output range.
iterator out() { return out_; }
FMT_DEPRECATED iterator begin() { return out_; }
// Advances the begin iterator to ``it``.
void advance_to(iterator it) { out_ = it; }
internal::locale_ref locale() { return loc_; }
};
template <typename Char>
using buffer_context =
basic_format_context<std::back_insert_iterator<internal::buffer<Char>>,
Char>;
using format_context = buffer_context<char>;
using wformat_context = buffer_context<wchar_t>;
/**
\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);
static const bool is_packed = num_args < internal::max_packed_args;
using value_type = conditional_t<is_packed, internal::value<Context>,
basic_format_arg<Context>>;
// If the arguments are not packed, add one more element to mark the end.
value_type data_[num_args + (!is_packed || num_args == 0 ? 1 : 0)];
friend class basic_format_args<Context>;
public:
static constexpr unsigned long long types =
is_packed ? internal::encode_types<Context, Args...>()
: internal::is_unpacked_bit | num_args;
FMT_DEPRECATED static constexpr unsigned long long TYPES = types;
format_arg_store(const Args&... args)
: data_{internal::make_arg<is_packed, Context>(args)...} {}
};
/**
\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`.
See `~fmt::arg` for lifetime considerations.
\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:
using size_type = unsigned;
using format_arg = basic_format_arg<Context>;
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; }
internal::type type(unsigned index) const {
unsigned shift = index * 4;
return static_cast<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_.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 an alias to make symbols readable.
struct format_args : basic_format_args<format_context> {
template <typename... Args>
format_args(Args&&... args)
: basic_format_args<format_context>(std::forward<Args>(args)...) {}
};
struct wformat_args : basic_format_args<wformat_context> {
template <typename... Args>
wformat_args(Args&&... args)
: basic_format_args<wformat_context>(std::forward<Args>(args)...) {}
};
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::buffer<Char>> : std::true_type {};
namespace internal {
template <typename OutputIt>
struct is_contiguous_back_insert_iterator : std::false_type {};
template <typename Container>
struct is_contiguous_back_insert_iterator<std::back_insert_iterator<Container>>
: is_contiguous<Container> {};
template <typename Char> struct named_arg_base {
basic_string_view<Char> name;
// Serialized value<context>.
mutable char data[sizeof(basic_format_arg<buffer_context<Char>>)];
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..., typename S, FMT_ENABLE_IF(!is_compile_string<S>::value)>
inline void check_format_string(const S&) {}
template <typename..., typename S, FMT_ENABLE_IF(is_compile_string<S>::value)>
void check_format_string(S);
template <typename S, typename... Args, typename Char = char_t<S>>
inline format_arg_store<buffer_context<Char>, Args...> make_args_checked(
const S& format_str, const Args&... args) {
check_format_string<Args...>(format_str);
return {args...};
}
template <typename Char>
std::basic_string<Char> vformat(basic_string_view<Char> format_str,
basic_format_args<buffer_context<Char>> args);
template <typename Char>
typename buffer_context<Char>::iterator vformat_to(
buffer<Char>& buf, basic_string_view<Char> format_str,
basic_format_args<buffer_context<Char>> args);
} // namespace internal
/**
\rst
Returns a named argument to be used in a formatting function.
The named argument holds a reference and does not extend the lifetime
of its arguments.
Consequently, a dangling reference can accidentally be created.
The user should take care to only pass this function temporaries when
the named argument is itself a temporary, as per the following example.
**Example**::
fmt::print("Elapsed time: {s:.2f} seconds", fmt::arg("s", 1.23));
\endrst
*/
template <typename S, typename T, typename Char = char_t<S>>
inline internal::named_arg<T, Char> arg(const S& name, const T& arg) {
static_assert(internal::is_string<S>::value, "");
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;
/** Formats a string and writes the output to ``out``. */
// GCC 8 and earlier cannot handle std::back_insert_iterator<Container> with
// vformat_to<ArgFormatter>(...) overload, so SFINAE on iterator type instead.
template <typename OutputIt, typename S, typename Char = char_t<S>,
FMT_ENABLE_IF(
internal::is_contiguous_back_insert_iterator<OutputIt>::value)>
OutputIt vformat_to(OutputIt out, const S& format_str,
basic_format_args<buffer_context<Char>> args) {
using container = remove_reference_t<decltype(internal::get_container(out))>;
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,
FMT_ENABLE_IF(
is_contiguous<Container>::value&& internal::is_string<S>::value)>
inline std::back_insert_iterator<Container> format_to(
std::back_insert_iterator<Container> out, const S& format_str,
const Args&... args) {
return vformat_to(out, to_string_view(format_str),
{internal::make_args_checked(format_str, args...)});
}
template <typename S, typename Char = char_t<S>>
inline std::basic_string<Char> vformat(
const S& format_str, basic_format_args<buffer_context<Char>> 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
*/
// 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>>
inline std::basic_string<Char> format(const S& format_str,
const Args&... args) {
return internal::vformat(to_string_view(format_str),
{internal::make_args_checked(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,
FMT_ENABLE_IF(internal::is_string<S>::value)>
inline void print(std::FILE* f, const S& format_str, const Args&... args) {
vprint(f, to_string_view(format_str),
internal::make_args_checked(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,
FMT_ENABLE_IF(internal::is_string<S>::value)>
inline void print(const S& format_str, const Args&... args) {
vprint(to_string_view(format_str),
internal::make_args_checked(format_str, args...));
}
FMT_END_NAMESPACE
#endif // FMT_CORE_H_
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