use List::Util qw( reduce );

my %ops = (
    add => sub { reduce { $a + $b } @_ },
    multiply => sub { reduce { $a * $b } @_ },
    # etc ...
);

my $op = shift or die "You must specify an operation followed by numbe
+rs.\n";
die "Non-numeric input.\n" if grep /\D/, @ARGV;
die "Invalid operation.\n" unless exists $ops{$op};

print "$op (@ARGV)= ". $ops->(@ARGV) . "\n";

[download]
Except, even that's too much repetition. 
use List::Util qw( reduce );

my %ops = (
    add => '+',
    multiply => '*',
    # etc ...
);

%ops = map {
    $_ => eval q(sub { reduce { $a ) . $ops{$_} . q( $b } @_ })
} keys %ops;

# And so forth.

[download]
Learn CPAN, young padawan. It is rare that someone hasn't already solved at least part of whatever it is you're looking at. Writing core Perl for more than 50% of a program is a sign of "I don't know CPAN," not brilliance.

Update: Fixed typo s/op/ops/ inside eval.

My criteria for good software:
  1. Does it work?
  2. Can someone else come in, make a change, and be reasonably certain no bugs were introduced?

In reply to Re^2: Simple add and multiply subroutines by dragonchild
in thread Simple add and multiply subroutines by negzero7

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