First of all, a character class already means "one of these characters", so your pipe isn't doing what you think it is. It would match |123. So that should be [+-]. It's also not necessary to escape the plus sign within a character class. Then, to say "zero or one of these," append ? to it, giving you [+-]? . You can also drop the .* from the beginning and .*$ from the end, since they're implied anyway. That gets your regex down to /([+-]?\d+)/ .

Aaron B.
My Woefully Neglected Blog, where I occasionally mention Perl.

In reply to Re: pull out num from str by aaron_baugher
in thread pull out num from str by icoder

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