use warnings;
use strict;

my %c = ( hey=>'Joe',
	  where=>'you goin\'',
	  with=>'that gun in your hand');

if (defined $c{Hendrix}) {
	print "Jimi is alive and well\n";
}

foreach ( sort keys %c ) {
	print "Key : $_ => $c{$_}\n";
}

##</code><code>##

$hash{key} = undef; #defined $hash{key} false, exists $hash{key} true

##</code><code>##

perl -e 'print "How sweet does a rose smell? "; chomp ($n = <STDIN>); $rose = "smells sweet to degree $n"; *other_name = *rose; print "$other_name\n"'