There are lots of ways to do this. Here's one which matches how Perl works internally when it needs to decide if something is numeric: 

   use Scalar::Util qw(looks_like_number);

   if (looks_like_number($foo)) {
       print "It could be a number.\n";
   } else {
       print "It's just a string.\n";
   }

[download]

Other solutions could involve regexes from Regexp::Common or coded by hand.

-sam

In reply to Re: Checking for data types by samtregar
in thread Checking for data types by Anonymous Monk

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