operator<<,>>(std::filesystem::path)
From cppreference.com
< cpp | filesystem | path
template< class CharT, class Traits > std::basic_ostream<CharT,Traits>& |
(1) | (since C++17) |
template< class CharT, class Traits > std::basic_istream<CharT,Traits>& |
(2) | (since C++17) |
Performs stream input or output on the path p
. std::quoted is used so that spaces do not cause truncation when later read by stream input operator.
These function templates are not visible to ordinary unqualified or qualified lookup , and can only be found by argument-dependent lookup when std::filesystem::path is an associated class of the arguments. This prevents undesirable conversions in the presence of a using namespace std::filesystem; using-directive.
Parameters
os | - | stream to perform output on |
is | - | stream to perform input on |
p | - | path to insert or extract |
Return value
1) os
2) is
Exceptions
(none)
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 2989 | C++17 | allowed insertion of everything convertible to path in the presence of a using-directive
|
made hidden friend |
Possible implementation
First version |
---|
template< class CharT, class Traits > std::basic_ostream<CharT,Traits>& operator<<( std::basic_ostream<CharT,Traits>& os, const path& p ) { os << std::quoted(p.string<CharT,Traits>()); return os; } |
Second version |
template< class CharT, class Traits > std::basic_istream<CharT,Traits>& operator>>( std::basic_istream<CharT,Traits>& is, path& p ) { std::basic_string<CharT, Traits> t; is >> std::quoted(t); p = t; return is; } |
Example
Run this code
#include <iostream> #include <filesystem> int main() { std::cout << std::filesystem::current_path() << '\n'; }
Possible output:
"/home/user"