Hello cellmates, I'm sitting staring at page 107 of the Learning Perl book and as far as I can see I'm doing exactly as required but....... All I want to do is ensure that a parameter supplied to a subroutine is exactly 3 digits. Nothing but numbers should be in this parameter. Easy? Well I thought so but the following example only fails if less than 3 numbers are supplied. If more than 3 numbers are supplied - even if some of the extra characters are non-digits - it passes the test!(?) Am I guily of an obvious typo or am I missing the point? 
#!/usr/bin/perl -w
#
use strict ;
#
my $step = 'a123aaaa' ;  # Produces True message
#
if ($step =~ /\d{3}/) {
   print "\n\tIt's true :: <$step>!\n" ;
}
else
{
   print "\n\tIt's false :: <$step>!\n" ;
}

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This parameter must be exactly 3 characters in length and all the characters MUST be digits. What am I doing wrong? Be gentle I've already gone bald scratching my head over this one!

In reply to Another RegExp question by Ronnie

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