`<charconv>`

The following functions provide character conversion support for safe integer types using Boost.Charconv.

Using this header requires Boost.Charconv headers to be present.

to_chars

to_chars converts a safe integer value into a character buffer specified by [first, last).

#include <boost/safe_numbers/charconv.hpp>

namespace boost::safe_numbers {

template <detail::unsigned_integral BasisType>
constexpr auto to_chars(char* first, char* last,
                        const detail::unsigned_integer_basis<BasisType> value,
                        int base = 10) -> charconv::to_chars_result;

} // namespace boost::safe_numbers

Parameters

first, last - character buffer to write to
value - the safe integer value to convert
base - integer base (default: 10), must be between 2 and 36

Return Value

Returns boost::charconv::to_chars_result:

struct to_chars_result
{
    char* ptr;
    std::errc ec;

    friend constexpr bool operator==(const to_chars_result& lhs, const to_chars_result& rhs) noexcept = default;
    constexpr explicit operator bool() const noexcept { return ec == std::errc{}; }
};

ptr - pointer to one past the last character written on success, or last on failure
ec - error code (std::errc{} on success, std::errc::value_too_large if buffer is too small)

from_chars

from_chars parses a string from [first, last) and converts it into a safe integer value.

#include <boost/safe_numbers/charconv.hpp>

namespace boost::safe_numbers {

template <detail::unsigned_integral BasisType>
constexpr auto from_chars(const char* first, const char* last,
                          detail::unsigned_integer_basis<BasisType>& value,
                          int base = 10) -> charconv::from_chars_result;

} // namespace boost::safe_numbers

Parameters

first, last - character range to parse
value - reference to safe integer to store the result
base - integer base (default: 10), must be between 2 and 36

Return Value

Returns boost::charconv::from_chars_result:

struct from_chars_result
{
    const char* ptr;
    std::errc ec;

    friend constexpr bool operator==(const from_chars_result& lhs, const from_chars_result& rhs) noexcept = default;
    constexpr explicit operator bool() const noexcept { return ec == std::errc{}; }
};

ptr - pointer to the first character not matching the pattern, or last if all characters matched
ec - error code (std::errc{} on success, std::errc::invalid_argument if no valid conversion, std::errc::result_out_of_range if value overflows)

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