How to access data from arrays with XML::Simple

ccarden has asked for the wisdom of the Perl Monks concerning the following question:

I began a similar thread on this topic, but this seems more to be a fundamental lack of understanding of arrays in Perl. It has me more than scratching my head. I've read through the perldocs and am missing something.

I've never pretended to be a great Perl programmer, but I really shouldn't be falling down on points like this. After 6 or 7 years of this, you'd think I'd actually know something. Maybe I should take up singing in a punk band.

Could someone direct me to documentation that will help me understand how to solve the following ...

The code:

#!/usr/bin/perl -w

use XML::Simple;
# qw(:strict);

my $ref = XMLin("xmlTest3.xml", forcearray=>1, keyattr=>{wrapper=>"nam
+e"});
my $wrapName = "testName 1.0.3";
print "$ref->{wrapper}->{$wrapName}->{script}\n";
print "$ref->{wrapper}->{$wrapName}->{envVar}->[0]->{value}\n";

# How do I enumerate the contents of the tags such as envVar and parm?
# The following only gives me an address to the array.
foreach my $pName ($ref->{wrapper}->{$wrapName}->{envVar}) {
    print $pName;
}
[download]

The data:

<config>
    <wrapper name="testName 1.0.3" script="/usr/people/ltorvalds/wrapp
+er.pl" app="/usr/bin/testApp.exe">
        <envVar name="TMPDIR" value="/usr/tmp"/>
        <envVar name="TEMPDIR" value="/usr/tmp"/>
        <parm name="pad" value="4"/>
        <parm name="me" value="0"/>
        <parm name="mf" value="0"/>
        <parm name="s" value="\$startFrame"/>
        <parm name="e" value="\$endFrame"/>
        <parm name="b" value="\$byFrame"/>
        <parm name="im" value="\$cacheDir\$qmJob.\$suffix"/>
        <parm name="of" value="\$fileExt"/>
    </wrapper>
    <wrapper name="testName2" script="/usr/people/wgates/wrapper2.pl" 
+engine="/usr/bin/testApp2.exe">
        <envVar name="MAYA_LOCATION" value="\$appPath"/>
        <envVar name="MAYA_SCRIPT_PATH" value="/data/render_common/scr
+ipts"/>
        <envVar name="TMPDIR" value="/usr/tmp"/>
        <envVar name="TEMPDIR" value="/usr/tmp"/>
        <parm name="pad" value="4"/>
        <parm name="me" value="0"/>
        <parm name="mf" value="0"/>
        <parm name="s" value="\$startFrame"/>
        <parm name="e" value="\$endFrame"/>
        <parm name="b" value="\$byFrame"/>
        <parm name="im" value="\$cacheDir\$qmJob.\$suffix"/>
        <parm name="of" value="\$fileExt"/>
    </wrapper>
</config>
[download]

Thanks for any input.

Comment on How to access data from arrays with XML::Simple Select or Download Code

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Re: How to access data from arrays with XML::Simple by jeffa (Bishop) on Oct 14, 2003 at 21:22 UTC
When dealing with complex datastructures, always bring Data::Dumper along for the ride. Here is some code that enumurates through the param elements of the "testName 1.0.3" <wrapper> tag: `use strict; use warnings; use XML::Simple; use Data::Dumper; my $ref = XMLin(\*DATA, forcearray=>1, keyattr=>{wrapper=>"name"}); # feel free to uncomment these Dumps #print Dumper $ref; for (@{$ref->{wrapper}{'testName 1.0.3'}{parm}}) { #print Dumper $_; while(my ($k,$v) = each %$_) { print "$k => $v\n"; } } __DATA__ <config> ... rest of XML ...` [download] Be sure and check out tye's excellent References quick reference also. jeffa L-LL-L--L-LL-L--L-LL-L-- -R--R-RR-R--R-RR-R--R-RR B--B--B--B--B--B--B--B-- H---H---H---H---H---H--- (the triplet paradiddle with high-hat)	[reply] [d/l]

Replies are listed 'Best First'.

Re: How to access data from arrays with XML::Simple
by jeffa (Bishop) on Oct 14, 2003 at 21:22 UTC

Data::Dumper

use strict;
use warnings;

use XML::Simple;
use Data::Dumper;

my $ref = XMLin(\*DATA, forcearray=>1, keyattr=>{wrapper=>"name"});

# feel free to uncomment these Dumps
#print Dumper $ref;

for (@{$ref->{wrapper}{'testName 1.0.3'}{parm}}) {

   #print Dumper $_;

   while(my ($k,$v) = each %$_) {
      print "$k => $v\n";
   }
}

__DATA__
<config>
 ... rest of XML ...
[download]

tye

References quick reference

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

[reply]
[d/l]