>perl -we"sub trim(@); sub trim($) {}"
Prototype mismatch: sub main::trim (@) vs ($) at -e line 1.

##</code><code>##

>perl -we"trim('abc'); sub trim($) {}"
main::trim() called too early to check prototype at -e line 1.

##</code><code>##

>perl -we"sub trim {} sub trim($) {}"
Prototype mismatch: sub main::trim: none vs ($) at -e line 1.
Subroutine trim redefined at -e line 1.