std::experimental::filesystem::path::append, std::experimental::filesystem::path::

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< cpp‎ | experimental‎ | fs‎ | path
Experimental
Technical Specification
Filesystem library (filesystem TS)
Library fundamentals (library fundamentals TS)
Library fundamentals 2 (library fundamentals TS v2)
Library fundamentals 3 (library fundamentals TS v3)
Extensions for parallelism (parallelism TS)
Extensions for parallelism 2 (parallelism TS v2)
Extensions for concurrency (concurrency TS)
Extensions for concurrency 2 (concurrency TS v2)
Concepts (concepts TS)
Ranges (ranges TS)
Reflection (reflection TS)
Mathematical special functions (special functions TR)
Experimental Non-TS
Pattern Matching
Linear Algebra
std::execution
Contracts
2D Graphics
path& operator/ = ( const path& p ) ;
(1) (filesystem TS)
template < class Source >
path& operator/ = ( const Source& source ) ;
(2) (filesystem TS)
template < class Source >
path& append( const Source& source ) ;
(3) (filesystem TS)
template < class InputIt >
path& append( InputIt first, InputIt last ) ;
(4) (filesystem TS)
1) First, appends the preferred directory separator to this, except if any of the following conditions is true:
* the separator would be redundant (*this already ends with a separator).
* *this is empty, or adding it would turn a relative path to an absolute path in some other way.
* p is an empty path.
* p.native() begins with a directory separator.
Then, appends p.native() to the pathname maintained by *this
2,3) Same as (1), but accepts any std::basic_string
4) Same as (1), but accepts any iterator pair that designates a multicharacter string.

Parameters

p - pathname to append
source - std::basic_string
first, last - pair of LegacyInputIterator
Type requirements
-
InputIt must meet the requirements of LegacyInputIterator
-
The value type of InputIt must be one of the encoded character types (char, wchar_t, char16_t and char32_t

Return value

*this

Exceptions

May throw filesystem_error on underlying OS API errors or std::bad_alloc

Example

#include <experimental/filesystem>
#include <iostream>
namespace fs = std::experimental::filesystem;
 
int main()
{
    fs::path p1 = "C:";
    p1 /= "Users"; // does not insert a separator
                   // "C:Users" is a relative path in Windows
                   // adding directory separator would turn it to an absolute path
    std::cout << "\"C:\" / \"Users\" == " << p1 << '\n';
    p1 /= "batman"; // inserts fs::path::preferred_separator, '\' on Windows
    std::cout << "\"C:\" / \"Users\" / \"batman\" == " << p1 << '\n';
}

Possible output:

"C:" / "Users" == "C:Users"
"C:" / "Users" / "batman" == "C:Users\batman"

See also

concatenates two paths without introducing a directory separator
(public member function)
concatenates two paths with a directory separator
(function)