filenameExt

fnstring filenameExt(string filename) @trusted

Gets the extension portion of a filename.

Returns the extension including the leading dot. If no extension is found, returns an empty string.

filename Filename to extract extension from

The extension including the dot (e.g., ".txt"), or empty string

if no extension is found.

Example:

assert(filenameExt("file.txt") == ".txt");
assert(filenameExt("archive.tar.gz") == ".gz");
assert(filenameExt("noext") == "");