I believe checking a regex for failure can prevent many headaches later. 
#!/usr/bin/perl

use strict;
use warnings;

my $problem = '1 / 2 = ';
my ($number1, $number2, $operator);

if ($problem =~ /(\d+)\s*([-+*\/])\s*(\d+)/){
  ($number1, $number2, $operator) = ($1, $2, $3);
  print "$number1 $number2 $operator\n";
}
else{
  print "regex failed\n";
}

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I also agree with monarch that as you know what the operator can be you can use a character class.

FWIW. I always have to check the docs to check which characters need escaping. They say that:

The special characters for a character class are -]\^$ and are matched using an escape...
Now I'm sure that's a backslash in there. But I couldn't get the regex above to work without escaping the forward slash.

Anyone see what I'm missing here?

Update:

It's because I used the forward slash as the quote for the regex!

Many thanks to the monks in the CB.

In reply to Re: '+' to + by wfsp
in thread '+' to + by NateTut

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