Mid_Ager has asked for the wisdom of the Perl Monks concerning the following question:

Please be patient to this simple regex memory question: during parsing & remembering the var. (using $1, $2), I cannot get the right syntax for this - <Id>3456</Id> <Name>Scott Susan</Name> ..... Using this - m#(<Id>)(.*)(</Id>)#; print "1 - $1"; ... won't work! Anyone can shed some light on this? Thanks.

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Re: Regular Expression memory
by DamnDirtyApe (Curate) on Nov 21, 2002 at 22:52 UTC

    What exactly isn't working?

    my $str = '<Id>3456</Id>' ;
$str =~ m#(<Id>)(.*)(</Id>)# ;
print "1 - $1\n2 - $2\n3 - $3\n" ;

[ doug 14:49 ~ ]% perl test.pl
1 - <Id>
2 - 3456
3 - </Id>

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    BTW, if you're trying to parse XML, take a look at XML::Simple; it does a fine job.


    _______________
    DamnDirtyApe 
    Those who know that they are profound strive for clarity. Those who
would like to seem profound to the crowd strive for obscurity.
            --Friedrich Nietzsche
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[d/l]
      Thanks all replies. I figure out the problem - it's because the memory variables - $1,$2, still retains it's old value in next loop (while(<>) ) and doesn't show the correct "values"! Thanks again.
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Re: Regular Expression memory
by chromatic (Archbishop) on Nov 22, 2002 at 00:58 UTC

    What happens if the match fails? You need an if in there. 

    if (m|(<Id>)(.*?)(</Id>)|)
{
    print "1 - '$1'\n2 - '$2'\n3 - '$3'\n";
}
else
{
    print "Hmm, no match.  Is this what happened?\n";
}

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