This may be more than you need, but ISTR that one of the modules on the 2003 Perl Advent Calendar (sorry; I don't recall which day) was a module of ready-made regular expressions for common parsing tasks. One of them was for parsing numbers. It's robust enough to handle most common number formats. If you find that the simple solutions here miss some numbers that are formatted a little differently (e.g., have signs, decimal points, or whatever), you may want to look into that.

However, if all your numbers are plain regular ordinary vanilla-type natural numbers, the solutions above should work fine. I mostly included this suggestion for the benefit of someone who might find this thread in SuperSearch later and have more advanced needs.

update: valdez reminded me of the name of the module in question. It's Regexp::Common. 

$;=sub{$/};@;=map{my($a,$b)=($_,$;);$;=sub{$a.$b->()}}
split//,".rekcah lreP rehtona tsuJ";$\=$ ;->();print$/

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In reply to Re: getting a number from a string by jonadab
in thread getting a number from a string by shaezi

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