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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"; }
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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