Re: Worrying regex issue with 5.8.0

This doesn't appear to be a perl issue, but rather a Data::Dumper issue.

Why is Data::Dumper involved anyway?

use Data::Dumper;
my $re_bad  = qr'@@([A-Z$#@_#]*) (?! [A-Za-z0-9$#@_] )'x;
print Dumper $re_bad;
print "\n\n\n";
print $re_bad;
__END__
$VAR1 = qr/(?x-ism:@@([A-Z$#@_#]*) (?! [A-Za-z0-9$#@_] ))/;



(?x-ism:@@([A-Z$#@_#]*) (?! [A-Za-z0-9$#@_] ))
[download]

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Comment on Re: Worrying regex issue with 5.8.0 Download Code

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Re: Re: Worrying regex issue with 5.8.0 by ruscoekm (Monk) on Nov 15, 2002 at 08:48 UTC
Well, from your output, you appear not to get any spurious characters anyway. When I said above that Data::Dumper was not the issue, what I meant was that I was just using it to display the output. I originally observed the problem because the characters added to my regex were *, which caused the regex to be invalid (luckily, or I might not have spotted it for a while). However, Data::Dumper may yet be involved. When I run the following code: `use Data::Dumper; my $re_bad = qr'xx([A-Z$#@_!]) (?! [A-Za-z0-9$#@_] )'x; print $re_bad;` [download] the output is: `(?x-ism:xx([A-Z$#@_!]) (?! [A-Za-z0-9$#@_] )# )` [download] Note the spurious hash (or pound, if you prefer :-) at the end. Given the following code: `my $re_bad = qr'xx([A-Z$#@_!]) (?! [A-Za-z0-9$#@_] )'x; print $re_bad;` [download] the output is: `(?x-ism:xx([A-Z$#@_!]*) (?! [A-Za-z0-9$#@_] ) )` [download] However, this does not yet prove that Data::Dumper is the culprit. Given the sporadic nature of the symptoms, it may well be that simply using any module of the right "size" will produce the error. Kevin	[reply] [d/l] [select]
Re: Re: Worrying regex issue with 5.8.0 by ruscoekm (Monk) on Nov 15, 2002 at 10:35 UTC
Ok, latest summary... It appears that the error does not occur unless both Data::Dumper and /x are present. Since the error is so sporadic, it is hard to be sure. NB Just avoiding the use of Data::Dumper (say by using Dumpvalue instead) is not an option, since many CPAN modules which I am using themselves use Data::Dumper. I will hang on a bit longer, to see if anybody spots anything else, then submit a bug report. Cheers, Kevin	[reply]