Venerable Bretheren ( & Bretherenesses ),

I've been able to avoid DOM, SAX and XML in general and it has now caught up to me. After reading the available information it looks like XML::Twig is the right tool for what I'm attempting to do, but that was after some quick reading. (Unkown file lengths make potential memory problems for XML::Simple and XML::Twig just looks cleaner than XML::Parser.)

I need to create a script that can dynamically change the value of elements in a well formed XML file. A calling program will supply the name of the element to search for and the value to supply to it.

I had thought this should be a piece of cake, but I'm paying a bit of a price for avoiding XML. I can do this via a regex, but as this is a script that is liable to grow in it's functionality I figure I need to stop and get a clue how to do this right.

I've stolen this snippet from a node of mirods and it pretty much exposes my ignorance. mirod's original node is a replace of XML via an XML file, I've started to re-arange variable names and eliminated the updated XML file as I'm attempting to bring in the vars from an external program:

#!/bin/perl -w
use strict;
use XML::Twig;

my( $main_file, $search, $value )= @ARGV;

# get the info we need by loading the update file
#my $t_upd= new XML::Twig();
#$t_upd->parsefile( $upd_file);

#my $upd_badge_id = $t_upd->root->next_elt( 'badge_id')->text;
#my $upd_chore    = $t_upd->root->next_elt( 'jobs');

# Process the main file
my $orig = new XML::Twig( 
                            TwigHandlers => { $search => \&search, },
                              PrettyPrint => 'indented',
                           );

$orig->parsefile( $main_file );
$orig->flush;           # don't forget or the last closing tags won't 
+be printed

sub search { 
    my( $orig, $search )= @_;
    print "hrmmm\n";
    # just replace jobs if the previous badge_id is the right one
    if( $search->prev_elt( 'name' )->text eq $search ) {
       print "hrmmm\n";
       $orig->replace( $value ); 
    }
    $orig->flush;    # print and flush memory so only one job is in th
+ere at once
}

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coreolyn - exposure of ignorace is so eeew ya know?

In reply to XML Search and Replace by coreolyn

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