The reason is that you're using a character class which says "match at least 1 of anything in the class" so any string with a dot, a digit or a '-' sign in it will match be (incorrectly) satisfied in the in the if ...

I suspect you are after something a little more forceful:
$long !~ /^([\-]*[\d]+[\.]*[\d]*)$/ (character classes are only left in for improving readability...)

This regex says: a leading "-" sign is optional, but must then have at least 1 digit, followed by an optional dot (to cater for cases where $long might equal an integer or 0) followed by optional digits...

In reply to Re: Stupid regex question - numerics by desemondo
in thread Stupid regex question - numerics by ultranerds

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