For my test, I have a simple XML structure: 
<config>
    <wrapper name="testName 1.0.3" script="/usr/people/ltorvalds/apps/
+wrapper.pl" app="testApp.exe">
        <envVar name="TMPDIR" value="/usr/tmp"/>
        <envVar name="APPDIR" value="/usr/bin"/>
    </wrapper>
</config>

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The following code successfully parses the xml file: 
#!/usr/bin/perl -w

use XML::Simple;

my $ref = XMLin();
my $wrapName = "testName 1.0.3";
print "$ref->{wrapper}->{$wrapName}->{script}\n";
print "$ref->{wrapper}->{$wrapName}->{envVar}->{TMPDIR}->{value}\n";

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... and correctly produces the following output ... 
/usr/people/ltorvalds/wrapper.pl
/usr/tmp

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Now, if I try to treat the <envVar> tags as an array, I run into trouble: 
print "$ref->{wrapper}->{$wrapName}->{envVar}->[0]->{value}\n";

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... produces a blank line. I assumed that this was because I needed to turn forceArray on, so I changed the call to XMLin(): 
my $ref = XMLin(xmlTest.xml, forceArray=>['envVar']);

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... but still I get the same blank line as output.

I suspect that I'm either using forceArray incorrectly or I'm using an invalid array reference. Any insight as to where my folly lies would be appreciated.

Update

Thanks for all of the input. What have I learned? I have learned that I need to:

  1. learn how to better use the debugger
  2. read the XML::Simple docs more carefully
  3. study up on hashes and arrays
It all pretty much boils down to rtfm, but I am grateful to all of you for the focused answers.

In reply to How do I correctly use arrays with XML::Simple? by ccarden

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