Hi -- I grabbed the is_numeric function from perfaq4. Either I am using it wrong, or it doesn't work. The following code asserts that undef and fish are numeric. What's going wrong? Thanks -- nop 
use POSIX qw(strtod);
use strict;

foreach (undef, qw(4 0 fish)) {
    print $_ , " is numeric? ", is_numeric($_), "\n";
}

sub getnum {
    my $str = shift;
    $str =~ s/^\s+//; $str =~ s/\s+$//; $! = 0;
    my($num, $unparsed) = strtod($str);
    if (($str eq '') || ($unparsed != 0) || $!) {return;} else {return
+ $num;} 
} 

sub is_numeric { defined scalar &getnum }

[download]

In reply to is_numeric from perlfaq4 by nop

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.