XML::LibXML and getting data from elements/nodes

From: Derrell Durrett (derrell.spam.durrett_at_xilinx.killer.com)
Date: 10/27/04

  • Next message: Tassilo v. Parseval: "Re: Namespace and comments on usefulness sought" 
    Date: Tue, 26 Oct 2004 18:50:15 -0600

    With the code below, I get the following output:

    Use of uninitialized value in concatenation (.) or string at
    /home/durrett/proto line 36.
    Use of uninitialized value in concatenation (.) or string at
    /home/durrett/proto line 36.
    Use of uninitialized value in concatenation (.) or string at
    /home/durrett/proto line 36.
    Use of uninitialized value in concatenation (.) or string at
    /home/durrett/proto line 36.

      

      

      

      

    (yes, that's literally 14 empty lines, though some have spaces)

    I would expect, based on my (very simplistic) understanding of perldoc
    XML::LibXML::Node's 'getData' entry:
           getData
               If the node has any content (such as stored in a text node )
               it can get requested through this function.

    to see something more akin to
    "platform_id from tblPlatform"
    "platform_id"

    etc.

    Obviously, my expectations are amiss. But how would I get to these
    data? Also, it makes no sense to me that half of the nodes returned by
    $root->getChildNodes give 'text' as their name (from a debugger session
    of the same code):

      DB<5> x map {$ARG->getName} $root->getChildNodes
    0 'text'
    1 'ibom-for-each'
    2 'text'
    3 'platform'
    4 'text'
    5 'ibom-next'
    6 'text'
    7 'installDrops'
    8 'text'

    Why is this the case?

    I'd gladly read a manual, if someone can please point me to one that is
    more expansive than the perldoc for XML:LibXML::Node.

    Thanks,

    Derrell
    __CODE__
    #! /tools/xgs/perl/5.8.5/bin/perl

    # External modules
    use strict;
    use warnings;
    use English;

    use XML::LibXML;

    # Create a parser object
    my $XML_parser = XML::LibXML->new();

    my $xml_piece = <<'EOXML';
    <?xml version="1.0" encoding="ISO-8859-1"?>

    <image
        image_id="tblImage.image_id"
        imageName="tblImage.imageName"
        installMode="tblImage.installMode"
    >
       <ibom-for-each>"platform_id from tblPlatform"</ibom-for-each>
       <platform platDesc="tblPlatform.platform">
       </platform>
       <ibom-next>"platform_id"</ibom-next>
       <installDrops>
       <ibom-for-each>"drop_id from tblInstallDrops where
    install_id=$install"</ibom-for-each>
       <ibom-next>"drop_id"</ibom-next>
       </installDrops>
    </image>
    EOXML

    # No default attributes.
    $XML_parser->complete_attributes(0);
    my $doc = $XML_parser->parse_string( $xml_piece );
    my $root = $doc->getDocumentElement;
    print map {"$ARG\n"} map {$ARG->getData} $root->getChildNodes; 

    -- 
Derrell Durrett
Xilinx, Inc. / Software Productivity Tools
Longmont, Colorado / 720.652.3843
***remove bits about .processed meats and .death from e-mail to reply
  • Next message: Tassilo v. Parseval: "Re: Namespace and comments on usefulness sought"

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