#!/usr/bin/perl -wT
use strict;
$|++;

use CGI qw( :standard );

my $result = '';
my %params = param();
if ( my $error = cgi_error() ) 
{
  print header( -status => $error );
  exit 0;
}

my $invalue = param( 'INVALUE' );
if ( defined $invalue ) 
 {
    eval{ local $^W = 1; $invalue + 0 };   ### Is Number?  (Line 19)
    if ( $@ ) 
       { $result = "$invalue is *not* a Number; Details: $@" }
    else
       { $result = "$invalue appears to be a number."; }
  }
else
  { $result = "Enter a value to test." }

print header( "text/html" ), 
      start_html('Test'),
      h1('Validation'),
      start_form(),
      p( $result ),
      p( "Please enter a number to test: ", textfield( 'INVALUE', '' ) ),
      p, submit,
      end_form, hr,"\n";
print end_html;

exit 1;