< cpp‎ | filesystem‎ | path
Defined in header <filesystem>
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.


[edit] 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.

[edit] 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)


constexpr void set_debug_format();

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


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.


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
  • 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.

[edit] Notes

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

[edit] Example

[edit] See also

defines formatting rules for a given type
(class template) [edit]