Re: XML::Twig newbie question

What I can't figure out is, how to pass the name in $file to the event handler, or conversely, how to associate the found attribute back to the $file. I'm probably missing something obvious, but can't puzzle it out. Any suggestions would be greatly appreciated.

You're missing closures, examples in XML::Twig traversing tree and storing in an array, XML::Twig n00b, Tutorials: Closure on Closures

for my $file ( ... ){
    my $filename = $file;
    my %filnameKeyref;
    my $topicref = sub {
       ...
       $filenameKeyref{ $filename };
       return;
    };

    my $twig= XML::Twig->new(  ... => $topicref );
    $twig->...;
}
[download]

Although you ought to write that as

for my $file ( ... ){
    my $complexAssociations = FooAssoc( $file );
    WalkAndTalk( $complexAssociations );
}
[download]

Comment on Re: XML::Twig newbie question Select or Download Code

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Re^2: XML::Twig newbie question by Jenda (Abbot) on Sep 18, 2012 at 07:15 UTC
Another way would be to make the subroutine curried (that is expecting to get the parameters separately, not all at once): `foreach my $file (@files){ # set up the XML parser: my $twig= XML::Twig->new( twig_handlers => { topicref => topicref_processing($file), xref => topicref_processing($file) }, ); $twig->parsefile($file); $twig->purge; } sub topicref_processing { my ($file) = @_; return sub { my($twig, $topicref) = @_; my($atts) = $topicref->atts(); if($$atts{'keyref'}){ ### associate this keyref with $file } } }` [download] Jenda Enoch was right! Enjoy the last years of Rome.	[reply] [d/l]
Re^3: XML::Twig newbie question by Anonymous Monk on Sep 18, 2012 at 07:31 UTC
Another way would be to make the subroutine curried (that is expecting to get the parameters separately, not all at once): Sure, you could write your closure that way ( the schönfinkeling way), but it gains you nothing in this example, it just takes a little more memory	[reply]
Re^4: XML::Twig newbie question by Jenda (Abbot) on Sep 18, 2012 at 10:57 UTC
Depends on the complexity of the subroutine. Maybe you do not want to include all that code in the middle of the loop. I would not sweat over the tiny difference in memory footprint or the cost of two additional subroutine calls. Use whatever makes the code easier to maintain. Jenda Enoch was right! Enjoy the last years of Rome.	[reply]
Re^3: XML::Twig newbie question by slugger415 (Monk) on Sep 18, 2012 at 15:50 UTC
"Curried?" sounds delicious! :-) Never heard that phrase before. Thank you, this is a simple solution that works perfectly for me. Scott	[reply]
Re^4: XML::Twig newbie question by Jenda (Abbot) on Sep 18, 2012 at 19:34 UTC
If you are feeling adventurous, have a look at Wikipedia. Another place might be the comp.lang.functional FAQ or maybe Currying Schonfinkelling. Jenda Enoch was right! Enjoy the last years of Rome.	[reply]
Re^2: XML::Twig newbie question by slugger415 (Monk) on Sep 18, 2012 at 15:52 UTC
Thank you for the suggestions; I will study the examples and try to understand them. A bit over my head at first sight. Scott	[reply]