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in reply to Adjacency List Processing in XML::Twig

I'd change the double-grep (which also happens to be a nested grep) to a grep-map: 
grep { $_->text eq $search_text }
map  { $_->children }
@data;

# or

grep $_->text eq $search_text,
map  $_->children,
@data;

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_____________________________________________________
Jeff[japhy]Pinyan: Perl, regex, and perl hacker.
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;

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Re: Re: Adjacency List Processing in XML::Twig
by chipmunk (Parson) on Aug 18, 2001 at 17:50 UTC
    Changing the nested grep to a grep map would change the semantics of the code. 
    grep { grep { $_->text eq $search_text } $_->children  } @data;

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    This nested grep returns a list of elements for which any child contains the search text. 
    grep { $_->text eq $search_text } map { $_->children } @data;

    [download]
    This grep map a list of individual children that contain the search text.

     

    With a search for 'menlo park', the nested grep returns two elements; one has the children '<city>menlo park</city>' and '<city>palo alto</city>', and the other has the children '<city>atherton</city>' and '<city>menlo park</city>'.

    The grep map, on the other hand, would just return '<city>menlo park</city>' and '<city>menlo park</city>'.

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[d/l]
[select]
      Oh, right. Sorry, princepawn, I misconstrued the purpose of that part of the code. That was silly of me.

      _____________________________________________________
      Jeff[japhy]Pinyan: Perl, regex, and perl hacker.
      s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;

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