NAME¶

std::experimental::filesystem::path::compare - std::experimental::filesystem::path::compare

Synopsis¶

int compare( const path& p ) const noexcept; (1) (filesystem TS)
int compare( const string_type& str ) const; (2) (filesystem TS)
int compare( const value_type* s ) const; (3) (filesystem TS)

Compares the lexical representations of the path and another path.

1) Returns a value less than, equal to or greater than 0 if the native
representation of the path (native()) is respectively lexicographically less than,
equal to or greater than the native representation of p (p.native()). Comparison is
performed element-wise, as if by iterating both paths from begin() to end().
2) Equivalent to compare(path(str)).
3) Equivalent to compare(path(s)).

Parameters¶

p - a path to compare to
str - a string representing path to compare to
s - a null-terminated string representing path to compare to

Return value¶

A value less than 0 if the path is lexicographically less than the given path.

A value equal to 0 if the path is lexicographically equal to the given path.

A value greater than 0 if the path is lexicographically greater than the given path.

Exceptions¶

2-3) May throw implementation-defined exceptions.

Notes¶

For two-way comparisons, binary operators may be more suitable.

Example¶

// Run this code

#include <iostream>
#include <experimental/filesystem>
namespace fs = std::experimental::filesystem;
void demo(int rc, fs::path p1, fs::path p2) {
if(rc < 0) std::cout << p1 << " < " << p2 << '\n';
else if(rc > 0) std::cout << p1 << " > " << p2 << '\n';
else if(rc == 0) std::cout << p1 << "==" << p2 << '\n';
}
int main() {
fs::path p1 = "/a/b/"; // as if "a/b/." for lexicographical iteration
fs::path p2 = "/a/b/#";
demo(p1.compare(p2), p1, p2);
demo(p1.compare("a/b/_"), p1, "a/b/_");
}

Output:¶

"/a/b/" > "/a/b/#"
"/a/b/" < "a/b/_"

See also¶

operator==
operator!=
operator< lexicographically compares two paths
operator<= (function)
operator>
operator>=