fmtlegacy/include/fmt/core.h
2018-10-24 10:52:02 -07:00

1505 lines
46 KiB
C++

// 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 50201
#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.
#if (defined(__GNUC__) && !defined(__EXCEPTIONS)) || \
FMT_MSC_VER && !_HAS_EXCEPTIONS
# define FMT_EXCEPTIONS 0
#else
# define FMT_EXCEPTIONS 1
#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 constexpr std::char_traits::length replacement for pre-C++17.
template <typename Char>
FMT_CONSTEXPR size_t length(const Char *s) {
const Char *start = s;
while (*s) ++s;
return s - start;
}
#if FMT_GCC_VERSION && !defined(__arm__)
FMT_CONSTEXPR size_t length(const char *s) { return std::strlen(s); }
#endif
#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
/** 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
/**
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
*/
FMT_CONSTEXPR basic_string_view(const Char *s)
: data_(s), size_(internal::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;
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>
inline typename std::enable_if<is_compile_string<S>::value, string_view>::type
to_string_view(const S &s) { return {s.data(), s.size() - 1}; }
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 {
template <typename S>
struct get_char_type {
typedef void char_type;
};
template <typename Char>
struct get_char_type<basic_string_view<Char>> {
typedef Char char_type;
};
using fmt::v5::to_string_view;
void to_string_view(...);
template <typename S>
struct has_to_string_view {
typedef typename get_char_type<decltype(to_string_view(internal::declval<S>()))>::char_type char_type;
static const bool value = !std::is_same<void, decltype(to_string_view(internal::declval<S>()))>::value;
};
template <typename S>
struct is_string : internal::has_to_string_view<S> {};
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<
internal::is_constructible<basic_string_view<Char>, T>::value &&
!internal::has_to_string_view<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 &&
!internal::is_constructible<basic_string_view<Char>, T>::value &&
!internal::has_to_string_view<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::has_to_string_view<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::has_to_string_view<S>::char_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 };
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());
}
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> 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 {};
}
};
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_;
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)
: parse_context_(format_str), out_(out), args_(ctx_args) {}
// 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_; }
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; }
};
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)
: base(out, format_str, ctx_args) {}
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 long long get_types() {
return IS_PACKED ?
static_cast<long long>(internal::get_types<Context, Args...>()) :
-static_cast<long long>(NUM_ARGS);
}
public:
#if FMT_USE_CONSTEXPR11
static FMT_CONSTEXPR11 long long TYPES = get_types();
#else
static const 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 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, typename ...Args>
inline format_arg_store<Context, Args...>
make_format_args(const Args &... args) { return {args...}; }
template <typename ...Args>
inline format_arg_store<format_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_;
};
typename internal::type type(unsigned index) const {
unsigned shift = index * 4;
unsigned long long mask = 0xf;
return static_cast<typename internal::type>(
(types_ & (mask << 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;
long long signed_types = static_cast<long long>(types_);
if (signed_types < 0) {
unsigned long long num_args =
static_cast<unsigned long long>(-signed_types);
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_(-static_cast<int64_t>(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;
}
unsigned max_size() const {
long long signed_types = static_cast<long long>(types_);
return static_cast<unsigned>(
signed_types < 0 ?
-signed_types : static_cast<long long>(internal::max_packed_args));
}
};
/** 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)...) {}
};
#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 = typename std::enable_if<internal::has_to_string_view<S>::value,
typename internal::has_to_string_view<S>::char_type>::type;
#define FMT_CHAR(S) char_t<S>
template <typename S, typename T>
using enable_if_string_t =
typename std::enable_if<internal::is_string<S>::value, T>::type;
#define FMT_ENABLE_IF_STRING(S, T) enable_if_string_t<S, T>
#else
template <typename S>
struct char_t : std::enable_if<
internal::has_to_string_view<S>::value,
typename internal::has_to_string_view<S>::char_type> {};
#define FMT_CHAR(S) typename char_t<S>::type
#define FMT_ENABLE_IF_STRING(S, T) \
typename std::enable_if<internal::is_string<S>::value, T>::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);
}
/**
\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;
}
/**
\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};
}
// This function template is deleted intentionally to disable nested named
// arguments as in ``format("{}", arg("a", arg("b", 42)))``.
template <typename S, typename T, typename Char>
void arg(S, internal::named_arg<T, Char>) = delete;
template <typename S>
typename buffer_context<FMT_CHAR(S)>::type::iterator vformat_to(
internal::basic_buffer<FMT_CHAR(S)> &buf, const S &format_str,
basic_format_args<buffer_context<FMT_CHAR(S)> > 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::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));
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_STRING(S, 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_STRING(S, 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_