I know this thread is old but it came up on google firstish. I searched, then came up with my own line, which I think works better than the regexp. I did not check all over, so most likely it is already around somewhere.

if ( $input+0 eq $input ){ print "it is a number!\n";}

Can someone point out the problem with this approach? Advantage for me: easy + quick, no problems with signs...

In reply to Re^3: How to check Inputs if Numeric by Anonymous Monk
in thread How to check Inputs if Numeric by kasmot

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