This slang allows you to put whitespace between the name of a subroutine and the opening parenthesis.
Be aware that this introduces ambiguous situations, like when you want to pass a List to a sub, or
when you need parenthesis around the condition after the keywords
while and so on...
foo 3, 5; # 15, as usual foo(3, 5); # also 15, as usual foo (3, 5); # 15, /o\ # It also allows to put space before argument lists in method calls: 42.fmt('-%d-'); # -42- 42.fmt: '-%d-'; # -42- 42.fmt ('-%d-'); # -42-