c:\@Work\Perl\monks>perl -le
"use strict;
 use warnings;
 ;;
 no warnings 'numeric';
 print 'numeric warning DISabled';
 ;;
 print q{'abc' }, isNumber('abc');
 print q{'123' }, isNumber('123');
 print q{123 },   isNumber(123);
 print q{undef }, isNumber(undef);
 print q{() },    isNumber();
 ;;
 sub isNumber {
   my $numeric = 1;
   use warnings 'numeric';
   local $SIG{__WARN__} = sub { $numeric = 0; };
   my $x = int $_[0];
   return $numeric;
   }
"
numeric warning DISabled
'abc' 0
'123' 1
123 1
undef 0
() 0