Hi.

Been doing some work to parse some kinda-of-log files and in doing so I just got the idea that 5.10 named capture buffers in regex are exactly what I need to get a quick "give me a category for an error depending on which part of this regex matched" thing.

So got to work on it and ... weird results happened. See following code demonstrating it: 

#!/usr/bin/perl -l
use Getopt::Std;
getopts( "fq", \%opt );

$line="ERROR 02052008-14:45 EDW08B50
...ocal/log2000/data/incoming/bk/xp/bk005466.edi
B: 1195043779       , RFT: AD0010043543
ERROR 02052008-14:45 EDW08B50 Closing date before today:2008-04-23";

$named_regex = '(?<DCSE>AD[^A]|NA|VN3)\S*';
$named_regex.= '$' if defined($opt{f});
$named_regex=qr/$named_regex/ if defined($opt{q});

$line=~/$named_regex/oms;
print join("=>",%+);

[download]

Simply put, if you call this program without arguments, it goes and uses string in $name_regex on the match. If you run it with -q, it first pass that string through qr//. The -f controls if the regex ends with a $ or not.

Should give always the same result right? It doesnt: 

# ./test.pl
DCSE=>AD0
# ./test.pl -q
DCSE=>AD0
# ./test.pl -f
DCSE=>AD0
# ./test.pl -fq

#

[download]

Somehow, that final $ on the strings means that, if $named_regex is just interpolated on the match, everything is ok, but if it is compiled as a regex first with qr//, then it isnt.

Any idea? From "it is evident that you are making a huge mistake, see..." from "better report it", anything is welcome

In reply to Weird bug with qr// and named capture buffers? Or just me? by Latro

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