if ( $scalar =~ /^[12345]+$/ ) {

Please note that $ also matches before a trailing \n character, and that this regex also matches "111\n". But I'd go for the negative match anyway, because it seems more natural to me. 

U28geW91IGNhbiBhbGwgcm90MTMgY
W5kIHBhY2soKS4gQnV0IGRvIHlvdS
ByZWNvZ25pc2UgQmFzZTY0IHdoZW4
geW91IHNlZSBpdD8gIC0tIEp1ZXJk

In reply to Re: Re: Detect presence of numbers 1-9 by Juerd
in thread Detect presence of numbers 1-9 by kiat

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