Hmmm, forgot about function calls like that. For some reason, I assumed perl would warn. But even this is warning free:

sub foo {shift}
sub bar {1}
print foo bar;
[download]

and just prints 1.

OTOH, in pre-5.6 days, when I was still using bare word file handles, I used all uppercase names, and I use all lowercase for subs, so /(?:print|...)\s+[A-Z]/ would have worked for my code.