Your nicknames hash seems a little strange because the keys are nicknames, but the values are a mixture of nicknames and formal names. It might be easier to access the data you want if you were to organize it differently. For example, I replaced your "nicknames" hash with a hash named "formal_name": 
use warnings;
use strict;

my %formal_name = (
    bill => 'william',
    will => 'william',
    abe  => 'abraham'
);

print_formal_name('will');
print_formal_name('sam');
print_all_nicknames('wiLLiam');
print_all_nicknames('thomas');

sub print_formal_name {
    my $nickname = shift;
    if (exists $formal_name{lc $nickname}) {
        print "The formal name for $nickname is ", ucfirst $formal_nam
+e{lc $nickname}, ".\n";
    }
    else {
        print "There is no formal name for $nickname.\n";
    }
}
sub print_all_nicknames {
    my $formalname = shift;
    my @nicknames;
    for my $nickname (keys %formal_name) {
        if ($formal_name{$nickname} eq lc $formalname) {
            push @nicknames, ucfirst $nickname . ', ';
        }
    }
    if (@nicknames) {
        $nicknames[$#nicknames] =~ s/, //;
        print ucfirst lc $formalname, " has these nicknames: ", @nickn
+ames, ".\n";
    }
    else {
        print ucfirst lc $formalname, " has no nicknames.\n";
    }
}

[download]
This prints: 
The formal name for will is William.
There is no formal name for sam.
William has these nicknames: Will, Bill.
Thomas has no nicknames.

[download]

In reply to Re: Help on format or better way to do..? by toolic
in thread Help on format or better way to do..? by learnperl

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