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();


"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:
new( OPTIONS )

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.


Returns true if ‘$name’ is equal to the name of the innermost currently opened element.


Returns the number of times the ‘$name’ appears in Names.


Ken MacLeod, ken@bitsko.slc.ut.us


perl(1), PerlSAX.pod(3)


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