Since an input validation is not likely to be a big user of system resources, an "optimal" solution is one that's easy to read and easy to change.

If the value is being used for something which could be character-based, such as a menu selection, use a hash, as suggested by demerphq. If it's going to be used for something that will be strictly numeric, I would just do something like this:

use strict;
use warnings;

my $entered_value;

my $min_allowed = 1;
my $max_allowed = 5;

if($entered_value =~ /^\d+\z/s and
   ($entered_value >= $min_allowed and $entered_value <= $max_allowed)
+)
   {
    do_magical_processing($entered_value);
    }
else{
    print "value must be a number no less than $min_value and not grea
+ter than $max_value\n";
}

[download]

And a grammatical quibble: "either" should only be used when there are exactly two choices.

emc

Insisting on perfect safety is for people who don't have the balls to live in the real world.

—Mary Shafer, NASA Dryden Flight Research Center

In reply to Re: Quicker way to do this IF statement 1-5 by swampyankee
in thread Quicker way to do this IF statement 1-5 by Anonymous Monk

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