extension

The extension of the file or directory last component.

Declaration

var `extension`: String? { get set }

Discussion

If lastComponent is nil or one of the special path components . or .., get returns nil and set does nothing.

If lastComponent does not contain a . anywhere, or only at the start, get returns nil and set will append a . and newValue to lastComponent.

Otherwise get returns everything after the last . and set will replace the extension.

Examples:

/tmp/foo.txt => txt
/Applications/Foo.app/ => app
/Applications/Foo.app/bar.txt => txt
/tmp/foo.tar.gz => gz
/tmp/.hidden => nil
/tmp/.hidden. => ""
/tmp/.. => nil

Example:

var path = "/tmp/file"
path.extension = "txt" // path is "/tmp/file.txt"
path.extension = "o"   // path is "/tmp/file.o"
path.extension = nil    // path is "/tmp/file"
path.extension = ""     // path is "/tmp/file."