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XML::Handler::Subs - a PerlSAX handler base class for calling user-defined subs
use XML::Handler::Subs;
package MyHandlers;
use vars qw{ @ISA };
sub s_NAME { my ($self, $element) = @_ };
sub e_NAME { my ($self, $element) = @_ };
$self->{Names}; # an array of names
$self->{Nodes}; # an array of $element nodes
$handler = MyHandlers->new(); $self->in_element($name); $self->within_element($name);
XML::Handler::Subs is a base class for PerlSAX handlers.
XML::Handler::Subs is subclassed to implement complete behavior and
to add element-specific handling.
Each time an element starts, a method by that name prefixed with `s_' is called with the element to be processed. Each time an element ends, a method with that name prefixed with `e_' is called. Any special characters in the element name are replaced by underscores.
Subclassing XML::Handler::Subs in this way is similar to XML::Parser's Subs style.
XML::Handler::Subs maintains a stack of element names,
`$self-{Names}', and a stack of element nodes, `$self-{Nodes}>'
that can be used by subclasses. The current element is pushed on the
stacks before calling an element-name start method and popped off the
stacks after calling the element-name end method. The
`in_element()' and `within_element()' calls use these stacks.
If the subclass implements `start_document()', `end_document()',
`start_element()', and `end_element()', be sure to use
`SUPER::' to call the the superclass methods also. See perlobj(1)
for details on SUPER::. `SUPER::start_element()' and
`SUPER::end_element()' return 1 if an element-name method is
called, they return 0 if no method was called.
XML::Handler::Subs does not implement any other PerlSAX handlers.
XML::Handler::Subs supports the following methods:
A basic `new()' method. `new()' takes a list of key, value
pairs or a hash and creates and returns a hash with those options; the
hash is blessed into the subclass.
in_element($name)
Returns true if `$name' is equal to the name of the innermost
currently opened element.
within_element($name)
Returns the number of times the `$name' appears in Names.
Ken MacLeod, ken@bitsko.slc.ut.us
perl(1), PerlSAX.pod(3)