Documentation for method f, assembled from the following types:
method f(--> Bool)
True if the invocant is a path that exists and is a file. The method will
X::IO::DoesNotExist if the path points to a non-existent filesystem entity.
TIP: use smartmatch with Pairs to perform multiple file tests.
method f(IO::Special: --> Bool)
The 'file' file test operator, always returns