quoting from PerlFaq4, here are various ways to check if a scalar variable is a number/whole/integer/float : 
if (/\D/)            { print "has nondigits\n" }
   if (/^\d+$/)         { print "is a whole number\n" }
   if (/^-?\d+$/)       { print "is an integer\n" }
   if (/^[+-]?\d+$/)    { print "is a +/- integer\n" }
   if (/^-?\d+\.?\d*$/) { print "is a real number\n" }
   if (/^-?(?:\d+(?:\.\d*)?|\.\d+)$/) { print "is a decimal number" }
   if (/^([+-]?)(?=\d|\.\d)\d*(\.\d*)?([Ee]([+-]?\d+))?$/)
            { print "a C float" }

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(Take your pick)... and if u want to use a negated regular expression, use the 
!~

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syntax instead of the 
=~

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In reply to Re: Equivalent to Integer? by screamingeagle
in thread Equivalent to Integer? by cdherold

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