You don't need a regex for this; use sprintf instead. Specificly...

@numbers = (2, 15, 1, 12, 123, 1234, 12345);
@numbers = map {sprintf '%4.4d', $_} @numbers;
print join ',', @numbers;
__END__
0002,0015,0001,0012,0123,1234,12345

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In reply to Re: Reg Exp Suggestion Needed by theorbtwo
in thread Reg Exp Suggestion Needed by Anonymous Monk

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