Font::TTF::XMLparse(3pm) User Contributed Perl Documentation Font::TTF::XMLparse(3pm)
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
perl v5.10.1 2011-02-25 Font::TTF::XMLparse(3pm)