Re: Passing data to XML::Twig twig_roots callbacks....?

Yep, the problem was a minor syntactic error nearby in my code
(parts not included here). The last version I emailed, which I'll
include again here for completeness, works as expected:

sub get_grandchild_info {
  my hash_ref = shift();
  return sub {
    my ($twig, $element) = @_;
    #blah blah, do something print-y here
  }
}

my $xmltwigobj = XML::Twig->new(
     twig_roots => {
       'Information/Child/Grandchild' =>
       get_grandchild_info($self),
     }
);

The named get_grandchild_info routine executes and sets up my
closure on instantiation. The anonymous routine is then called as
expected by the Twig parser as many times as are necessary.

Thanks all-

Jenda Krynicky wrote:
> From: Dustin Suchter <[email protected]>
>> So this code runs, but obviously doesn't pass my data. It loops the
>> expected number of times, given the XML it is parsing:
>>
>> sub get_grandchild_info {
>>   my hash_ref = shift();
>>   return sub {
>>     my ($twig, $element) = @_;
>>     #blah blah, do something print-y here
>>   }
>> }
>>
>> my $xmltwigobj = XML::Twig->new(
>>      twig_roots => {
>>        'Information/Child/Grandchild' =>
>>        get_grandchild_info,
>>      }
>> );
>>
>> If I change the object instantiation code to what immediately
>> follows, my subroutine executes precisely 1 time only:
>>
>> sub get_grandchild_info {
>>   my hash_ref = shift();
>>   return sub {
>>     my ($twig, $element) = @_;
>>     #blah blah, do something print-y here
>>   }
>> }
>>
>> my $xmltwigobj = XML::Twig->new(
>>      twig_roots => {
>>        'Information/Child/Grandchild' =>
>>        get_grandchild_info(),
>>      }
>> );
>>
>> And finally this version does the same thing, executing just the
>> first time the subroutine is "instantiated" - a term I'll use
>> lightly since I believe this is technically a closure-utilizing
>> callback, not an object:
>>
>> sub get_grandchild_info {
>>   my hash_ref = shift();
>>   return sub {
>>     my ($twig, $element) = @_;
>>     #blah blah, do something print-y here
>>   }
>> }
>>
>> my $xmltwigobj = XML::Twig->new(
>>      twig_roots => {
>>        'Information/Child/Grandchild' =>
>>        get_grandchild_info($self),
>>      }
>> );
>>
>> I'm guessing there's something wrong with the prototype for my
>> subroutine so $smltwigobj isn't really connecting with
>> get_granchild_info when I change the number of args... the question
>> is (a) why? and (b) how to fix that?
> 
> Without the actual code I can't tell. The last version (after fixig 
> the syntax) should be right. The get_grandchild_info() should be 
> called just once (when the $xmltwigobj is being created), but the 
> closure returned by that subroutine should be called several times.
> 
> Please create a complete script and example XML. 
> 
> Jenda
> ===== [email protected] === http://Jenda.Krynicky.cz =====
> When it comes to wine, women and song, wizards are allowed 
> to get drunk and croon as much as they like.
> 	-- Terry Pratchett in Sourcery
> 
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