Monks, I'm using the following to recognize 3 and 4 digit numbers. 
my $digits_4 = qr{ \b \d{4} \b }xms;


$text =~ s{ ($digits_4) }
          {<a href="resident-info.pl?do_what=view&unit=$1"><b>$1</b></
+a>}xmsg;
          
my $digits_3 = qr{ \b \d{3} \b }xms;
$text =~ s{ ($digits_3) }
          {<a href="resident-info.pl?do_what=view&unit=$1"><b>$1</b></
+a>}xmsg;

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It works, but it also tags numbers within a phone number 555-555-5555. How can I make it work only if there is a space before the 4 digits? That would preclude it from being recognized in a string of numbers such as dates and phone numbers. Thanks.

In reply to Recognizing 3 and 4 digit number by htmanning

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