->findnodes() returns an XML::XPath::NodeSet, not a (Perl) list of nodes.

See ->get_nodelist of that object.

That's not what the docs say, and that's not what the error message says. (It mentions "Node", not "NodeSet".)

The error message is actually spot on. The OP is trying to call the "exists" method of a node, but nodes don't have an "exists" method. The correct usage is

$tree->exists('path', $node)
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I was looking at <a href="http://search.cpan.org/~msergeant/XML-XPath-1.13/XPath.pm#findnodes%28$path,_$context%29">->findnodes, and there it says that.

But I remember hours of staring at various parts of the documentation, trying to piece together a whole, so there might be other parts that say something else.

I'm sorry, but I don't get it, but a node is a tree, and vice-versa.. what is the distinction?

Actually, another question.. the doc says that findnodes

"Returns a list of nodes found by $path, optionally in context $context. In scalar context returns an XML::XPath::NodeSet object."

I had taken that to mean that since I am invoking the method inside the braces for a foreach loop

foreach my $node ($tree->findnodes())

It would return a list of nodes.. Isn't that a list contest? Why would it be a scalar context?

Indeed, it should return the list of nodes in your case. I think I was just barking up the wrong tree, sorry.

thats what i thought too, and tried these changes:

foreach my $node($tree->findnodes('path')->get_nodelist(){
  if ($node->exists('path')){
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and alternatively

my $node_list = $tree->find('path');
foreach my $node($node_list->get_nodelist()){
  if ($node->exists('path')){
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I still get the same error..

perl allows you to create objects, and then you can define methods which those objects can call. XML::XPath is just some programmer's module that you can use to create XML::Xpath objects and call methods on those objects. exists() is one of those methods. It says so in the documentation.

But just because one perl programmer creates a module that defines a method does not mean that all perl objects can call that method. Objects can only call methods that were specifically defined for that object(or that they inherit from parent objects). XML::XPath::Node objects and XML::XPath objects are not the same thing.

Read ikegami's post again.

perl allows you to create objects, and then you can define methods which those objects can call. XML::XPath is just some programmer's module that you can use to create XML::Xpath objects and call methods on those objects. exists() is one of those methods. It says so in the documentation.

But just because one perl programmer creates a module that defines a method does not mean that all perl objects can call that method. Objects can only call methods that were specifically defined for that object(or that they inherit from parent objects). XML::Node objects and XML::XPath objects are not the same thing.

Read ikegami's post again.