Michael --
...and then Michael Norris said...
%
% This subroutine is supposed to chech the validity of an IP address. 4 numbers (1 -
255) separated by ".". But my regular expression doesn't seem to be working out for
me.
%
...
% if ($_[0] =~ m/([1-2][0..5]*[0..5]*)\.\1\.\1\.\\s*$/) {
I don't know the best answer to your question, but I do know that the
expression you've built doesn't limit to 1-255. Your rule says
one 1 or one 2
any number of 0-5
any number of 0-5
and so "1" and "155" work, but "186" doesn't work even though it should
and "1555555" works even though it shouldn't. Furthermore, I *think*
that by matching \1 repeatedly you've then said that only a.a.a.a or
b.b.b.b (where a or b matches the expression) works, rather than a.b.c.d
(you want to match the same expression, but I believe the \1 means the
same *result*).
It seems to me easiest split this into four pieces and check the value of
each, so something like
($p1,$p2,$p3,$p4) = split(/\./, $_[0])
foreach $p ($p1 $p2 $p3 $p4)
{
( $p > 0 ) && ( $p < 256 ) || die "whoa -- $p is not in range!";
}
would do the trick. You *might* want to ensure that only three dots, and
no non-numbers, are fed in, in which case you could first
m/[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+/ || die "only numbers and three dots!"
and then move on to checking the values. YMMV.
All of this code is untested and off the top of my newbie head. The two
tests could probably be combined into one, even, as well as everything
written more elegantly. But I *do* know that you'll need to start with a
regexp that DWYM,NWYS (does what you mean, not what you say :-)
HTH & HAND
:-D
--
David T-G * It's easier to fight for one's principles
(play) [EMAIL PROTECTED] * than to live up to them. -- fortune cookie
(work) [EMAIL PROTECTED]
http://www.justpickone.org/davidtg/ Shpx gur Pbzzhavpngvbaf Qrprapl Npg!
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