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std::filesy...::path::path(3)  C++ Standard Libary std::filesy...::path::path(3)

NAME
     std::filesystem::path::path - std::filesystem::path::path

Synopsis
	path()	noexcept;						     (1)
     (since C++17)
	path( const path& p  ); 					     (2)
     (since C++17)
	path(  path&&  p ) noexcept;					     (3)
     (since C++17)
	path( string_type&& source, format fmt = auto_format  );	     (4)
     (since C++17)
	template<  class  Source >					     (5)
     (since C++17)
	path( const Source& source, format fmt = auto_format );
	template< class InputIt  >					     (6)
     (since C++17)
	path( InputIt first, InputIt last, format fmt = auto_format );
	template< class Source >
	path(  const  Source& source, const std::locale& loc, format fmt =   (7)
     (since C++17)
	auto_format );
	template< class InputIt >
	path( InputIt first, InputIt last, const std::locale& loc,  format   (8)
     (since C++17)
	fmt = auto_format );

	Constructs a new path object.

	1) Constructs an empty path.
	2)  Copy  constructor.	Constructs a path whose pathname, in both native
     and generic
	formats, is the same as that of p.
	3) Move constructor. Constructs a path whose pathname,	in  both  native
     and generic
	formats,  is  the  same as that of p, p is left in valid but unspecified
     state.
	4-6) Constructs the path from a character sequence  (format  interpreted
     as specified
	by  fmt) provided by source (4,5), which is a pointer or an input itera-
     tor to a
	null-terminated character/wide character sequence, an  std::basic_string
     or an
	std::basic_string_view,  or  represented  as  a  pair of input iterators
     [first, last)
	(6). Any of the character types char,
	char8_t,
	(since C++20)char16_t, char32_t, wchar_t is allowed, and the  method  of
     conversion to
	the native character set depends on the character type used by source.

	  *  If the source character type is char, the encoding of the source is
     assumed to
	    be the native narrow encoding (so no conversion takes place on POSIX
     systems).

	  * If the source character type is char8_t, conversion  from  UTF-8  to
     (since C++20)
	    native filesystem encoding is used.

	  *  If the source character type is char16_t, conversion from UTF-16 to
     native
	    filesystem encoding is used.
	  * If the source character type is char32_t, conversion from UTF-32  to
     native
	    filesystem encoding is used.
	  *  If the source character type is wchar_t, the input is assumed to be
     the native
	    wide encoding (so no conversion takes places on Windows).
	7,8) Constructs the path from a character sequence  (format  interpreted
     as specified
	by  fmt) provided by source (7), which is a pointer or an input iterator
     to a
	null-terminated character sequence, an std::string, an std::string_view,
     or
	represented as a pair of input iterators [first,  last)  (8).  The  only
     character type
	allowed  is char. Uses loc to perform the character encoding conversion.
     If
	value_type   is   wchar_t,   converts	from   to   wide    using    the
     std::codecvt<wchar_t, char,
	std::mbstate_t>  facet	of  loc. Otherwise, first converts to wide using
     the
	std::codecvt<wchar_t, char, std::mbstate_t> facet and then  converts  to
     filesystem
	native	character  type  using std::codecvt<wchar_t,value_type> facet of
     loc.

	(5) and (7) participate in overload resolution only if Source  and  path
     are not the
	same type, and either:

	  *   Source  is  a  specialization  of  std::basic_string  or	std::ba-
     sic_string_view, or
	  * std::iterator_traits<std::decay_t<Source>>::value_type is valid  and
     denotes a
	    possibly const-qualified encoding character type (char,
	    char8_t,
	    (since C++20)char16_t, char32_t, or wchar_t).

Parameters
	p	    - a path to copy
		      std::basic_string, std::basic_string_view, pointer to a
	source	    - null-terminated character string, or input iterator with a
     character
		      value  type that points to a null-terminated character se-
     quence (the
		      character type must be char for overload (7))
	first, last - pair of LegacyInputIterators that specify a character  se-
     quence
	fmt	     - enumerator of type path::format which specifies how path-
     name format is
		      to be interpreted
	loc	    - locale that defines encoding conversion to use

Type requirements
	-
	InputIt must meet the requirements of LegacyInputIterator.
	-
	The value type of InputIt must be  one	of  the  character  types  char,
     wchar_t,
	char8_t,
	(since C++20)char16_t and char32_t to use the overload (6).
	-
	The value type of InputIt must be char to use the overload (8).

Exceptions
	2,4-8) May throw implementation-defined exceptions.

Notes
	For  portable  pathname  generation  from  Unicode  strings, see u8path.
     (until C++20)
	path constructor supports creation from UTF-8  string  when  the  source
     (since C++20)
	is a sequence of char8_t.

Example
     // Run this code

      #include <filesystem>
      #include <iostream>
      namespace fs = std::filesystem;

      int main()
      {
	  fs::path p1 = "/usr/lib/sendmail.cf"; // portable format
	  fs::path  p2	= "C:\\users\\abcdef\\AppData\\Local\\Temp\\"; // native
     format
	  fs::path p3 = U"D:/c<<.txt"; // UTF-32 string
	  fs::path p4 = u8"~/c.txt"; // UTF-8 string

	  std::cout << "p1 = " << p1 << '\n'
		    << "p2 = " << p2 << '\n'
		    << "p3 = " << p3 << '\n'
		    << "p4 = " << p4 << '\n';
      }

Output:
      p1 = "/usr/lib/sendmail.cf"
      p2 = "C:\\users\\abcdef\\AppData\\Local\\Temp\\"
      p3 = "D:/c<<.txt"
      p4 = "~/c.txt"

	Defect reports

	The following behavior-changing defect	reports  were  applied	retroac-
     tively to
	previously published C++ standards.

	   DR	 Applied to		 Behavior as published		    Cor-
     rect behavior
	LWG   3244   C++17	 constraint  that  Source  cannot  be  path  was
     added
			    missing

See also
	u8path			     creates a path from a UTF-8 encoded source
	(C++17)(deprecated in C++20) (function)

http://cppreference.com 	   2024.06.10	   std::filesy...::path::path(3)
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