"$_ = 'lll+ll'; #3+2
@add = m/(l+)\+(l+)/;
print "$_ = @add\n";

$_ = 'lll*ll'; #3*2
@mult = m/l(?=.*\*(l*))/g;
print "$_ = @mult\n";

$_ = 'lll';
@sqr = m/(l)(?=(l*))(?=(l*))/g;
print "$_ squared = @sqr\n";"
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Alright ;-) In this case, I would say Perl's string operation can also be used for simple computation: (indeed this is the way how human being started to learn numbers and math at the begining, and when we were little kids, each of us repeated this process)

my $a = '111';
my $b = '11';

print $a . $b, "\n"; # 3 + 2
print $a x length($b), "\n"; #3 * 2
print $a x length($a), "\n"; #sqr(3)
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