VERSION

version 2.087

SYNOPSIS

use Config::Model;
# define configuration tree object
my $model = Config::Model->new;
$model->create_config_class(
name => "Foo",
element => [
[qw/bar baz/] => {
type => 'leaf',
value_type => 'string',
level => 'important' ,
},
]
);
$model->create_config_class(
name => "MyClass",
element => [
foo_nodes => {
type => 'hash', # hash id
index_type => 'string',
level => 'important' ,
cargo => {
type => 'node',
config_class_name => 'Foo'
},
},
],
);
my $inst = $model->instance( root_class_name => 'MyClass' );
# create some Foo objects
$inst->config_root->load("foo_nodes:foo1 - foo_nodes:foo2 ") ;
my $my_leaf_cb = sub {
my ($iter, $data_r,$node,$element,$index, $leaf_object) = @_ ;
print "leaf_cb called for ",$leaf_object->location,"\n" ;
} ;
my $my_hash_cb = sub {
my ($iter, $data_r,$node,$element,@keys) = @_ ;
print "hash_element_cb called for element $element with keys @keys\n" ;
} ;
my $iterator = $inst -> iterator (
leaf_cb => $my_leaf_cb,
hash_element_cb => $my_hash_cb ,
);
$iterator->start ;
### prints
# hash_element_cb called for element foo_nodes with keys foo1 foo2
# leaf_cb called for foo_nodes:foo1 bar
# leaf_cb called for foo_nodes:foo1 baz
# leaf_cb called for foo_nodes:foo2 bar
# leaf_cb called for foo_nodes:foo2 baz

DESCRIPTION

This module provides a class that is able to iterate forward or backward a configuration tree. The iterator stops and calls back user defined subroutines on one of the following condition:

• A configuration item contains an error (mostly undefined mandatory values)
• A configuration item contains warnings and the constructor's argument "call_back_on_warning" was set.
• A configuration item has a "important" level and the constructor's argument "call_back_on_important" was set.. See level parameter for details.

The iterator supports going forward and backward (to support "back" and "next" buttons on a wizard widget).

CONSTRUCTOR

The constructor should be used only by Config::Model::Instance with the iterator method.

Creating an iterator

A iterator requires at least two kind of call-back: a call-back for leaf elements and a call-back for hash elements (which is also used for list elements).

These call-back must be passed when creating the iterator (the parameters are named "leaf_cb" and "hash_element_cb")

Here are the the parameters accepted by "iterator":

call_back_on_important

Whether to call back when an important element is found (default 0).

call_back_on_warning

Whether to call back when an item with warnings is found (default 0).

status

Specifies the status of the element scanned by the wizard (default 'standard').

leaf_cb

Subroutine called backed for leaf elements. See ``Callback prototypes'' in Config::Model::ObjTreeScanner for signature and details. (mandatory)

hash_element_cb

Subroutine called backed for hash elements. See ``Callback prototypes'' in Config::Model::ObjTreeScanner for signature and details. (mandatory)

Custom callbacks

By default, "leaf_cb" is called for all types of leaf elements (i.e enum. integer, strings, ...). But you can provide dedicated call-back for each type of leaf:

 enum_value_cb, integer_value_cb, number_value_cb, boolean_value_cb,
 uniline_value_cb, string_value_cb

Likewise, you can also provide a call-back dedicated to list elements with "list_element_cb"

Methods

start

Start the scan and perform call-back when needed. This function returns when the scan is completely done.

bail_out

When called, a variable is set so that all call_backs returns as soon as possible. Used to abort wizard.

go_forward

Set wizard in forward (default) mode.

go_backward

Set wizard in backward mode.

AUTHOR

Dominique Dumont, (ddumont at cpan dot org)

AUTHOR

Dominique Dumont

COPYRIGHT AND LICENSE

This software is Copyright (c) 2005-2016 by Dominique Dumont.

This is free software, licensed under:

  The GNU Lesser General Public License, Version 2.1, February 1999