std::filesystem::path::replace_extension

path& replace_extension( const path& replacement = path() );	(1)	(since C++17)

Replaces the extension with replacement or removes it when the default value of replacement is used.

Firstly, if this path has an extension(), it is removed from the generic-format view of the pathname.

Then, a dot character is appended to the generic-format view of the pathname, if replacement is not empty or does not begin with a dot character.

Then replacement is appended as if by operator+=(replacement)

Parameters

replacement

-

the extension to replace with

Return value

*this

Exceptions

(none)

Notes

The type of replacement is std::filesystem::path even though it is not intended to represent an object on the file system in order to correctly account for the filesystem character encoding.

Example

Run this code

#include <iostream>
#include <filesystem>
namespace fs = std::filesystem;
 
int main()
{
    fs::path p = "/foo/bar.jpeg";
    std::cout << "Was: " << p << '\n';
    p.replace_extension(".jpg");
    std::cout << "Now: " << p << '\n';
}

Output:

Was: "/foo/bar.jpeg"
Now: "/foo/bar.jpg"

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