Perl `basename` and `dirname` module-free implementations

file-basename.pl

# WHY would we need this?  For a situation where loading File::Basename isn't possible
# For example, in a BEGIN block, to tinker with @INC.

sub basename {
    my $file = shift;
    $file =~ s!^(?:.*/)?(.+?)(?:\.[^.]*)?$!$1!;
    return $file;
}

sub dirname {
    my $file = shift;
    $file =~ s!/?[^/]*/*$!!;
    return $file;
}