[ic] [interchange] Add numeric ordercheck

[Mike Heins]

Quoting Jon Jensen (interchange-cvs at icdevgroup.org):
> commit 528ff5442ed28dc74a665f81e43d132a072c15b7
> Author: Jon Jensen <jon at endpoint.com>
> Date:   Thu Mar 25 09:36:54 2010 -0600
> 
>     Add numeric ordercheck
>     
>     Allowed:
>     1
>     0.5
>     -1
>     -1.0
>     -1.0000
>     -0.5
>     
>     Disallowed:
>     1.
>     .1
>     1.1.1
>     +1
>     1,0
>     
>     Thanks to Ton Verhagen for making it happen.

Hmm. This is no definition of numeric I know of.

If it is for a SQL purpose, perhaps. I don't know enough to check
that. I will tell you MySQL and Postgres both accept +1, 1. and .1 just
fine, as does Perl.

I think perhaps I would prefer:

	use Scalar::Util qw/looks_like_number/;

sub {
    my ($ref, $name, $value, $msg) = @_;
    use Scalar::Util qw/looks_like_number/;

    if (looks_like_number($value)) {
        return (1, $name, '');
    }
    else {
        return (0, $name, defined($msg) ? $msg : 'not numeric');
    }
}

Here is a test:

my @tests = qw/
     True:
     1
     0.5
     -1
     -1.0
     -1.0000
     -0.5
     Disallowed:
     1.
     .1
     1.1.1
     +1
     1,0
/;

use Scalar::Util qw/looks_like_number/;
for(@tests) {
	my $result = looks_like_number($_) ? 'true' : 'false';
	printf "\ttesting %-20s: %s\n", "'$_'", $result;
}

This prints:

	testing 'True:'             : false
	testing '1'                 : true
	testing '0.5'               : true
	testing '-1'                : true
	testing '-1.0'              : true
	testing '-1.0000'           : true
	testing '-0.5'              : true
	testing 'Disallowed:'       : false
	testing '1.'                : true
	testing '.1'                : true
	testing '1.1.1'             : false
	testing '+1'                : true
	testing '1,0'               : false

-- 
Mike Heins
Perusion -- Expert Interchange Consulting    http://www.perusion.com/
phone +1.765.328.4479  <mike at perusion.com>

Just because something is obviously happening doesn't mean something
obvious is happening. --Larry Wall