```{index} single: XML::Parser::Style::Tree ``` # XML::Parser::Style::Tree Tree style parser ## SYNOPSIS ```perl use XML::Parser; my $p = XML::Parser->new(Style => 'Tree'); my $tree = $p->parsefile('foo.xml'); ``` ## DESCRIPTION This module implements XML::Parser's Tree style parser. When parsing a document, `parse()` will return a parse tree for the document. Each node in the tree takes the form of a tag, content pair. Text nodes are represented with a pseudo-tag of "0" and the string that is their content. For elements, the content is an array reference. The first item in the array is a (possibly empty) hash reference containing attributes. The remainder of the array is a sequence of tag-content pairs representing the content of the element. So for example the result of parsing: ```text Hello thereHowdydo ``` would be: ```perl Tag Content ================================================================== [foo, [{}, head, [{id => "a"}, 0, "Hello ", em, [{}, 0, "there"]], bar, [ {}, 0, "Howdy", ref, [{}]], 0, "do" ] ] ``` The root document "foo", has 3 children: a "head" element, a "bar" element and the text "do". After the empty attribute hash, these are represented in it's contents by 3 tag-content pairs. ### Entity Expansion The underlying Expat parser always expands predefined XML entity references (`<`, `>`, `&`, `"`, `'`) in both text content and attribute values before they reach the Tree style handlers. This is required by the XML specification and cannot be prevented. For example, `<` in the source XML will appear as `<` in the resulting tree structure. If you need access to the original unexpanded text, consider using the handler-based API with the `original_string` method on the Expat object instead of the Tree style.