NAME

       Font::TTF::XMLparse - provides support for XML parsing. Requires Expat module
       XML::Parser::Expat

SYNOPSIS

           use Font::TTF::Font;
           use Font::TTF::XMLparse;

           $f = Font::TTF::Font->new;
           read_xml($f, $ARGV[0]);
           $f->out($ARGV[1]);

DESCRIPTION

       This module contains the support routines for parsing XML and generating the Truetype font
       structures as a result. The module has been separated from the rest of the package in
       order to reduce the dependency that this would bring, of the whole package on XML::Parser.
       This way, people without the XML::Parser can still use the rest of the package.

       The package interacts with another package through the use of a context containing and
       element 'receiver' which is an object which can possibly receive one of the following
       messages:

       XML_start
           This message is called when an open tag occurs. It is called with the context, tag
           name and the attributes. The return value has no meaning.

       XML_end
           This messages is called when a close tag occurs. It is called with the context, tag
           name and attributes (held over from when the tag was opened). There are 3 possible
           return values from such a message:

           undef   This is the default return value indicating that default processing should
                   occur in which either the current element on the tree, or the text of this
                   element should be stored in the parent object.

           $context
                   This magic value marks that the element should be deleted from the parent.
                   Nothing is stored in the parent. (This rather than '' is used to allow 0
                   returns.)

           anything
                   Anything else is taken as the element content to be stored in the parent.

           In addition, the context hash passed to these messages contains the following keys:

           xml This is the expat xml object. The context is also available as $context->{'xml'}{'
               mycontext'}. But that is a long winded way of not saying much!

           font
               This is the base object that was passed in for XML parsing.

           receiver
               This holds the current receiver of parsing events. It may be set in associated
               application to adjust which objects should receive messages when. It is also
               stored in the parsing stack to ensure that where an object changes it during
               XML_start, that that same object that received XML_start will receive the
               corresponding XML_end

           stack
               This is the parsing stack, used internally to hold the current receiver and
               attributes for each element open, as a complete hierarchy back to the root
               element.

           tree
               This element contains the storage tree corresponding to the parent of each element
               in the stack. The default action is to push undef onto this stack during XML_start
               and then to resolve this, either in the associated application (by changing
               $context->{'tree'}[-1]) or during XML_end of a child element, by which time we
               know whether we are dealing with an array or a hash or what.

           text
               Character processing is to insert all the characters into the text element of the
               context for available use later.

METHODS

AUTHOR

       Martin Hosken <http://scripts.sil.org/FontUtils>.

LICENSING

       Copyright (c) 1998-2016, SIL International (http://www.sil.org)

       This module is released under the terms of the Artistic License 2.0.  For details, see the
       full text of the license in the file LICENSE.