Re: regex puzzle

bingfeng zhao wrote: 
See following sample code:

<CODE>
use warnings;
use strict;
my @address = ("http://test";, "http://";, "www", "", "ftp:/foo" );
for (@address)
{
print "\"$_\" passed! \n" if /^((http|ftp):\/\/)?.+$/;
}
</CODE> 

the running result is:
"http://test"; is valid.
"http://"; is valid.
"www" is valid.
"ftp:/foo" is valid.

why "http://"; and "ftp:/foo" can pass the check?

Because ((http|ftp):\/\/) is optional ( the ? following it does that ),
so any line with anything between the start and end of the line will pass.

--
Flemming Greve Skovengaard           FAITH, n.
a.k.a Greven, TuxPower                   Belief without evidence in what is told
<dsl58893@xxxxxxxxxxxxxxxx>              by one who speaks without knowledge,
4112.38 BogoMIPS                         of things without parallel.

.