use strict;
use warnings;
sub println {
       print((@_ ? join($,, @_) : $_))."\n";
   }
println "hello world";
println "goodbye world";

# output:
Use of uninitialized value in join or string at foo line 4.
Use of uninitialized value in join or string at foo line 4.
hello worldgoodbye world
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Secondly, your implementation is broken

my bad.

sub println {
    $\ = "\n";
    @_ = ($_) unless @_;
    print @_;
}
[download]

And now you call me "bitchy" in your root node and only admit to updating it to comply with strict and warnings, still failing to admit that your originally posted code was just plain broken. Talk about your second rate programmers. Please go find some third rate programmers to hang out with.