# std::filesystem::path::path

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< cpp‎ | filesystem‎ | path

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 > path( const Source& source, format fmt = auto_format ); | (5) | (since C++17)
template< class InputIt > path( InputIt first, InputIt last, format fmt = auto_format ); | (6) | (since C++17)
template< class Source > path( const Source& source, const std::locale & loc, format fmt = auto_format ); | (7) | (since C++17)
template< class InputIt > path( InputIt first, InputIt last, const std::locale & loc, format fmt = auto_format ); | (8) | (since C++17)

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 iterator 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 native filesystem encoding is used.

(since C++20)

  - 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::basic_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
source | - | std::basic_string, std::basic_string_view, pointer to a null-terminated character string, or input iterator with a character value type that points to a null-terminated character sequence (the character type must be char for overload (7))
first, last | - | pair of LegacyInputIterators that specify a character sequence
fmt | - | enumerator of type `path::format` which specifies how pathname 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 is a sequence of char8_t. | (since C++20)

### 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:/猫.txt"; // UTF-32 string
        fs::path p4 = u8"~/狗.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:/猫.txt"
    p4 = "~/狗.txt"

### Defect reports

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

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

### See also

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

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