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Standard library header <charconv> (C++17)

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This header is part of the strings library.

Classes

specifies formatting for std::to_chars and std::from_chars
(enum) [edit]
the return type of std::from_chars
(class) [edit]
the return type of std::to_chars
(class) [edit]

Functions

converts a character sequence to an integer or floating-point value
(function) [edit]
(C++17)
converts an integer or floating-point value to a character sequence
(function) [edit]

[edit] Synopsis

namespace std {
  // floating-point format for primitive numerical conversion
  enum class chars_format {
    scientific = /* unspecified */,
    fixed = /* unspecified */,
    hex = /* unspecified */,
    general = fixed | scientific
  };
 
 
  // primitive numerical output conversion
  struct to_chars_result { // freestanding
    char* ptr;
    errc ec;
    friend bool operator==(const to_chars_result&, const to_chars_result&) = default;
    constexpr explicit operator bool() const noexcept { return ec == errc{}; }
  };
 
  constexpr
  to_chars_result to_chars(char* first, char* last, // freestanding
                           /* integer-type */ value, int base = 10);
  to_chars_result to_chars(char* first, char* last, // freestanding
                           bool value, int base = 10) = delete;
  to_chars_result to_chars(char* first, char* last, // freestanding-deleted
                           /* floating-point-type */ value);
  to_chars_result to_chars(char* first, char* last, // freestanding-deleted
                           /* floating-point-type */ value, chars_format fmt);
  to_chars_result to_chars(char* first, char* last, // freestanding-deleted
                           /* floating-point-type */ value,
                           chars_format fmt, int precision);
 
  // primitive numerical input conversion
  struct from_chars_result { // freestanding
    const char* ptr;
    errc ec;
    friend bool operator==(const from_chars_result&, const from_chars_result&) = default;
    constexpr explicit operator bool() const noexcept { return ec == errc{}; }
  };
 
  constexpr
  from_chars_result from_chars(const char* first, // freestanding
                               const char* last, /* integer-type */& value,
                               int base = 10);
  from_chars_result from_chars(const char* first, // freestanding-deleted
                               const char* last, /* floating-point-type */& value,
                               chars_format fmt = chars_format::general);
}