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

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< 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.

### 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

set_debug_format | enables to format the pathname as an escaped string (public member function)
parse | parses the format specifier as specified by path-format-spec (public member function)
format | 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`

### Example

| This section is incomplete Reason: no example

### See also

formatter (C++20) | defines formatting rules for a given type (class template)

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