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

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Ranges library(C++20)
Algorithms library
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Filesystem library(C++17)
Concurrency support library(C++11)
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Filesystem library

Classes

filesystem::path
filesystem::filesystem_error
filesystem::directory_entry
filesystem::directory_iterator
filesystem::recursive_directory_iterator
filesystem::file_status
filesystem::space_info

filesystem::file_type
filesystem::file_time_type
filesystem::perms
filesystem::perm_options
filesystem::copy_options
filesystem::directory_options

Functions

filesystem::absolute
filesystem::canonicalfilesystem::weakly_canonical
filesystem::relativefilesystem::proximate
filesystem::copy
filesystem::copy_file
filesystem::copy_symlink
filesystem::create_directory filesystem::create_directories
filesystem::create_hard_link
filesystem::create_symlink filesystem::create_directory_symlink
filesystem::current_path
filesystem::temp_directory_path

filesystem::exists
filesystem::equivalent
filesystem::file_size
filesystem::hard_link_count
filesystem::last_write_time
filesystem::permissions
filesystem::read_symlink
filesystem::remove filesystem::remove_all
filesystem::rename
filesystem::resize_file
filesystem::space
filesystem::status filesystem::symlink_status

File types

filesystem::is_block_file
filesystem::is_character_file
filesystem::is_directory
filesystem::is_empty
filesystem::status_known

filesystem::is_fifo
filesystem::is_other
filesystem::is_regular_file
filesystem::is_socket
filesystem::is_symlink

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std::filesystem::path

Member types

Member constants

path::native_formatpath::generic_formatpath::auto_format

Member functions

path::path
path::~path
path::operator=
path::assign
path::appendpath::operator/=
path::concatpath::operator+=
path::clear
path::make_preferred
path::remove_filename
path::replace_filename
path::replace_extension
path::swap
path::compare
path::beginpath::end

path::c_strpath::nativepath::operator string_type
path::stringpath::u8stringpath::u16stringpath::u32stringpath::wstring
path::generic_stringpath::generic_u8stringpath::generic_u16stringpath::generic_u32stringpath::generic_wstring
path::lexically_normalpath::lexically_relativepath::lexically_proximate

Path decomposition

path::root_name
path::root_directory
path::root_path
path::relative_path
path::parent_path
path::filename
path::stem
path::extension
path::empty

path::has_root_pathpath::has_root_namepath::has_root_directorypath::has_relative_pathpath::has_parent_pathpath::has_filenamepath::has_stempath::has_extension
path::is_absolutepath::is_relative

Non-member functions

operator==operator!=operator<operator<=operator>operator>=operator<=>

(until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20)

operator/
operator<<operator>>
swap(std::filesystem::path)
hash_value
u8path

Helper classes

hash<std::filesystem::path>

formatter<std::filesystem::path>

(C++26)

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

The template specialization ofstd::formatter for thestd::filesystem::path class allows users to convert a pathname to its textual representation usingformatting functions. This specialization isdebug-enabled.

[edit]Format specification

The syntax of format specificationspath-format-spec is:


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

fill-and-align andwidth have the same meaning as instandard format specification.

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

Theg option is used to specify that the pathname is ingeneric-format representation.

[edit]Member functions

set_debug_format	enables to format the pathname as anescaped string (public member function)
parse	parses the format specifier as specified bypath-format-spec (public member function)
format	writes the formatted output as specified bypath-format-spec (public member function)

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

constexprvoid set_debug_format();

Allows the current object to format pathname as anescaped string.

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

constexprauto parse(std::basic_format_parse_context<CharT>& ctx) ->std::basic_format_parse_context<CharT>::iterator;

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

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

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

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

Lets bep.generic<std::filesystem::path::value_type>() if theg option is used, otherwisep.native(). Writess intoctx.out() as specified bypath-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 withU+FFFD REPLACEMENT CHARACTER if
- std::is_same_v<CharT,char> istrue,
- std::is_same_v<typename path::value_type,wchar_t> istrue, and
- ordinary literal encoding is UTF-8.
Otherwise, no transcoding is performed ifstd::is_same_v<typename path::value_type, CharT> istrue.
Otherwise, transcoding is implementation-defined.