XML::Filter::Tee(3) Send SAX events to multiple processor, with switching

VERSION

version 0.46

SYNOPSIS


my $t = XML::Filter::Tee->new(
{ Handler => $h0 },
{ Handler => $h1 },
{ Handler => $h2 },
...
);
## Altering the handlers list:
$t->set_handlers( $h0, $h1, $h2, $h3 );
## Controlling flow to a handler by number and by reference:
$t->disable_handler( 0 );
$t->enable_handler( 0 );
$t->disable_handler( $h0 );
$t->enable_handler( $h0 );
## Use in a SAX machine (though see L<XML::SAX::Pipeline> and
## L<XML::SAX::Tap> for a more convenient way to build a machine
## like this):
my $m = Machine(
[ Intake => "XML::Filter::Tee" => qw( A B ) ],
[ A => ">>log.xml" ],
[ B => \*OUTPUT ],
);

DESCRIPTION

XML::Filter::Tee is a SAX filter that passes each event it receives on to a list of downstream handlers.

It's like XML::Filter::SAXT in that the events are not buffered; each event is sent first to the tap, and then to the branch (this is different from XML::SAX::Dispatcher, which buffers the events). Unlike XML::Filter::SAXT, it allows it's list of handlers to be reconfigured (via ``set_handlers'') and it allows control over which handlers are allowed to receive events. These features are designed to make XML::Filter::Tee instances more useful with SAX machines, but they to add some overhead relative to XML::Filter::SAXT.

The events are not copied, since they may be data structures that are difficult or impossibly to copy properly, like parts of a C-based DOM implementation. This means that the handlers must not alter the events or later handlers will see the alterations.

NAME

XML::Filter::Tee - Send SAX events to multiple processor, with switching

METHODS

new
    my $t = XML::Filter::Tee->new(
        { Handler => $h0 },
        { Handler => $h1 },
        { Handler => $h2 },
        ...
    );
set_handlers
    $t->set_handlers( $h0, $h1, $h2 );
    $t->set_handlers( {
            Handler => $h0,
        },
        {
            Handler => $h1,
        },
    );

Replaces the current list of handlers with new ones.

Can also name handlers to make enabling/disabling them by name easier: 

    $m->set_handlers( {
            Handler => $validator,
            Name    => "Validator",
        },
        {
            Handler => $outputer,
        },
    );
    $m->disable_handler( "Validator" );
disable_handler
    $t->disable_handler( 0 );            ## By location
    $t->disable_handler( "Validator" );  ## By name
    $t->disable_handler( $h0 );          ## By reference

Stops sending events to the indicated handler.

enable_handler
    $t->enable_handler( 0 );            ## By location
    $t->enable_handler( "Validator" );  ## By name
    $t->enable_handler( $h0 );          ## By reference

Stops sending events to the indicated handler.

AUTHOR

    Barrie Slaymaker <[email protected]>

COPYRIGHT

    Copyright 2002, Barrie Slaymaker, All Rights Reserved

You may use this module under the terms of the Artistic, GNU Public, or BSD licenses, as you choose.

AUTHORS

COPYRIGHT AND LICENSE

This software is copyright (c) 2013 by Barry Slaymaker.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

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