Access your argument in the subroutine like this:

#!/usr/bin/perl -w 

use strict;

sub do_this_cool_function {
  my %args = (
        -retire     => "never",
        -pizza     => "cheese",
        -payscale   => 0,
        -beer      => "guiness",
        @_,         # argument pair list goes here
    );

    print "I wanna retire $args{-retire} if my pizza is $args{-pizza}.
+\n";
}

do_this_cool_function(-retire=>'early', -payscale=>-55.00, -pizza=>'co
+ld', -beer=>'none');
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i don't get your error by the way. the only error your function call gives, is the following, because you didn't quote 'none':

Bareword "none" not allowed while "strict subs" in use at ./test.pl li
+ne 17.
Unquoted string "none" may clash with future reserved word at ./test.p
+l line 17.
Execution of ./test.pl aborted due to compilation errors.
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