You can use a following construction which look like switch operator:

#!/usr/bin/perl -w

use strict;

SWITCH: for(<STDIN>) {
/^[Yy]o$/       && { print "whats up"; last; };
/^[Nn]ot much$/ && { print "cool"; last; };
   print "HUH?"
}
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Mice were crying and stinging but went on nibbling the cactus ... 
                                              ( The facts of life )
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