The paranthesis makes it pass the strict test. I guess strict figures that if you use paranthesis, you know what you are doing. It only detects barewords outside of curlies and not in front of the => operator, if I recall correctly. And if it finds one, it checks if it knows about any such sub (but it only checks backwards in the script). Thus, many place their main code last, after all the subs to be sure, and others (like me) place it first, and use &sub, which I think is the best. But I am drifting...
in reply to Invalid sub ignored on use strict;
Here are some examples on what passes strict and not:
So what has happened is that your solid code has not ever been evaluated to false... yet. ;-)
# With a subroutine defined:
foo(); # Prints "Stuff"
&foo; # This too.
foo; # Blows up, no such sub... yet.
foo; # Is also ok, prints "Stuff"
# With no subroutine defined:
bar(); # Compiles, blows up at runtime *if* executed
&bar; # This one too
bar; # Blows up at compile time
You have moved into a dark place.
It is pitch black. You are likely to be eaten by a grue.