std::formatter<std::filesystem::path>

std::formatter<std::filesystem::path> - cppreference.com

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`template< class CharT > struct formatter<std::filesystem::path, CharT>;`		(since C++26)

The template specialization of std::formatter for the std::filesystem::path class allows users to convert a pathname to its textual representation using formatting functions. This specialization is debug-enabled.

Format specification

The syntax of format specifications path-format-spec is:


fill-and-align (optional) width (optional) `?`(optional) `g`(optional)

fill-and-align and width have the same meaning as in standard format specification.

The ? option is used to format the pathname as an escaped string.

The g option is used to specify that the pathname is in generic-format representation.

Member functions

	enables to format the pathname as an escaped string (public member function)
	parses the format specifier as specified by path-format-spec (public member function)
	writes the formatted output as specified by path-format-spec (public member function)

std::formatter<std::filesystem::path>::set_debug_format

`constexpr void set_debug_format();`

Allows the current object to format pathname as an escaped string.

std::formatter<std::filesystem::path>::parse

`constexpr auto parse( std::basic_format_parse_context<CharT>& ctx ) -> std::basic_format_parse_context<CharT>::iterator;`

Parses the format specifiers as a path-format-spec and stores the parsed specifiers in the current object.

Returns an iterator past the end of the path-format-spec.

std::formatter<std::filesystem::path>::format

`template< class FormatContext > auto format( const std::filesystem::path& p, FormatContext& ctx ) const -> FormatContext::iterator;`

Let s be p.generic<std::filesystem::path::value_type>() if the g option is used, otherwise p.native(). Writes s into ctx.out() as specified by path-format-spec.

For character transcoding of the pathname:

The pathname is transcoded from the native encoding for wide character strings to UTF-8 with maximal subparts of ill-formed subsequences substituted with U+FFFD REPLACEMENT CHARACTER if
- std::is_same_v<CharT, char> is true,
- std::is_same_v<typename path::value_type, wchar_t> is true, and
- ordinary literal encoding is UTF-8.
Otherwise, no transcoding is performed if std::is_same_v<typename path::value_type, CharT> is true.
Otherwise, transcoding is implementation-defined.

Returns an iterator past the end of the output range.

Notes

Feature-test macro	Value	Std	Feature
`__cpp_lib_format_path`	`202403L`	(C++26)	formatting support for `std::filesystem::path`