Look and say sequence (Perl)

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This is a simple Perl program to generate look-and-say sequences such as the Conway sequence. 

<<look_and_say_sequence.pl>>=
sub look_and_say {
	my $generator = shift;
	my $seq_length = shift;
	my @sequence = ($generator);
	for (my $i = 1; $i <= $seq_length; $i++) {
		my $val = $sequence[-1];
		my $nextval = "";
		my $char = substr($val,0,1);
		while ($char && $val =~ m/$char+/g) {
			$nextval .= length($&).$char;
			$char = substr($',0,1);
		}
		push(@sequence, $nextval);
	}
	return @sequence
}
@conway = look_and_say(3,10);
print join(", ",@conway);
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