NAME¶
XML::Handler::Subs - a PerlSAX handler base class for calling user-defined subs
SYNOPSIS¶
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);
DESCRIPTION¶
"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.
- 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.
AUTHOR¶
Ken MacLeod, ken@bitsko.slc.ut.us
SEE ALSO¶
perl(1),
PerlSAX.pod(3)