Quote

%s() called too early to check prototype
(W prototype) You’ve called a function that has a prototype before the parser saw a
definition or declaration for it, and Perl could not check that the call conforms to
the prototype. You need to either add an early prototype declaration for the
subroutine in question, or move the subroutine definition ahead of the call to get
proper prototype checking. Alternatively, if you are certain that you’re calling the
function correctly, you may put an ampersand before the name to avoid the warning.
See perlsub.

Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live. -- Damian Conway in "Perl Best Practices"
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