plucky (3) Font::TTF::XMLparse.3pm.gz

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.