How about qr(): 
my $IsNumber = qr/^\d+$/;

print "yes\n" if 42 =~ $IsNumber;

[download]

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to (jeffa) Re: double deference a variable by jeffa
in thread double deference a variable by coreywride

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