Perl 5.8.1's stock Scalar::Util has looks_like_number(). Here's a little workout to show what it can and can't do, 

use Scalar::Util 'looks_like_number';
my @candidates = qw/ 1 1.1 1,1 0E0 0e0 0377 100_000 0xdeadbeef/;

print $_,
      looks_like_number($_)? ' is' : ' is not',
      ' a number.',
      $/
    for @candidates;

__END__
1 is a number.
1.1 is a number.
1,1 is not a number.
0E0 is a number.
0e0 is a number.
0377 is a number.
100_000 is not a number.
0xdeadbeef not is a number.

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After Compline,
Zaxo

In reply to Re: Re: numeric comparison by Zaxo
in thread numeric comparison by hotshot

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