You are right. A look ahead is required in the second regex:     /^[+-]?(?=\d|\.\d)\d*(?:\.\d*)?(?:[Ee][+-]?\d+)?$/

--
John.

In reply to Re: Re: Matching floats according to perlfaq4 by jmcnamara
in thread Matching floats according to perlfaq4 by jmcnamara

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