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Regular expression behavior

Given the script:

--------
use strict;
use warnings;

my $text = 'blob:blob';

doit($text);
doit($text);
doit($text);

sub doit
{
my ($aa) = @_;

if( $aa =~ m?[^:]+:.*? ) {
print "Good!\n";
}
else {
print "Bad! \n";
}
}

----

This produces the output:

Good!
Bad!
Bad!

-----

I think that I may have a mistake on the regular expression syntax,
but why does this show one behavior once and another behavior for all
subsequent calls?

If I change the regex to m/[^:]+:.*/ it works fine.

I was under the impression that I could use any delimiter around my
regex, but I seem to be mistaken.

-Adam
Jul 19 '05 #1
1 1491
Adam Briska wrote:
Given the script:

--------
use strict;
use warnings;

my $text = 'blob:blob';

doit($text);
doit($text);
doit($text);

sub doit
{
my ($aa) = @_;

if( $aa =~ m?[^:]+:.*? ) {
print "Good!\n";
}
else {
print "Bad! \n";
}
}

----

This produces the output:

Good!
Bad!
Bad!

-----

I think that I may have a mistake on the regular expression syntax,
but why does this show one behavior once and another behavior for all
subsequent calls?

If I change the regex to m/[^:]+:.*/ it works fine.

I was under the impression that I could use any delimiter around my
regex, but I seem to be mistaken.


So it seems.

Why didn't you check the docs for the m// operator before asking here?

--
Gunnar Hjalmarsson
Email: http://www.gunnar.cc/cgi-bin/contact.pl

Jul 19 '05 #2

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