XML::Filter::DataIndenter - SAX2 Indenter for data oriented XML


    use XML::Filter::DataIndenter;

    use XML::SAX::Machines qw( Pipeline );

    Pipeline( XML::Filter::DataIndenter => \*STDOUT );


ALPHA CODE ALERT: This is the first release. Feedback and patches welcome.

In data oriented XML, leaf elements (those which contain no elements) contain only character content, all other elements contain only child elements and ignorable whitespace. This filter consumes all whitespace not in leaf nodes and replaces it with whitespace that indents all elements. Character data in leaf elements is left unmolested.

This filter assumes you're emitting data oriented XML. It will die if it sees non-whitespace character data outside of a leaf element. It also dies if it sees start-tag / end-tag mismatch, just as a service to the programmer.

Processing instructions and comments are indented as though they were leaf elements except when they occur in leaf elements.


This document:


gets reindented as:


(plus or minus a space in each PI, depending on your XML writer).


Considers only [\r\n \t] to be whitespace; does not think about the broader Unicode definition of whitespace. This will be addressed when time and need permit.


    Copyright 2003, R. Barrie Slaymaker, Jr., All Rights Reserved


You may use this module under the terms of the BSD, Artistic, oir GPL licenses, any version.


Barrie Slaymaker <>