Config::Model::AnyId(3) Base class for hash or list element


version 2.087


use Config::Model;
# define configuration tree object
my $model = Config::Model->new;
name => "Foo",
element => [
[qw/foo bar/] => {
type => 'leaf',
value_type => 'string'
name => "MyClass",
element => [
plain_hash => {
type => 'hash',
index_type => 'string',
cargo => {
type => 'leaf',
value_type => 'string',
bounded_hash => {
type => 'hash', # hash id
index_type => 'integer',
# hash boundaries
min_index => 1, max_index => 123, max_nb => 2,
# specify cargo held by hash
cargo => {
type => 'leaf',
value_type => 'string'
bounded_list => {
type => 'list', # list id
max_index => 123,
cargo => {
type => 'leaf',
value_type => 'string'
hash_of_nodes => {
type => 'hash', # hash id
index_type => 'string',
cargo => {
type => 'node',
config_class_name => 'Foo'
my $inst = $model->instance( root_class_name => 'MyClass' );
my $root = $inst->config_root;
# put data
my $steps = 'plain_hash:foo=boo bounded_list=foo,bar,baz
bounded_hash:3=foo bounded_hash:30=baz
hash_of_nodes:"foo node" foo="in foo node" -
hash_of_nodes:"bar node" bar="in bar node" ';
$root->load( steps => $steps );
# dump resulting tree
print $root->dump_tree;


This class provides hash or list elements for a Config::Model::Node.

The hash index can either be en enumerated type, a boolean, an integer or a string.


AnyId object should not be created directly.

Hash or list model declaration

A hash or list element must be declared with the following parameters:
Mandatory element type. Must be "hash" or "list" to have a collection element. The actual element type must be specified by "cargo =" type> (See ``CAVEATS'').
Either "integer" or "string". Mandatory for hash.
Whether to keep the order of the hash keys (default no). (a bit like Tie::IxHash). The hash keys are ordered along their creation. The order can be modified with swap, move_up or move_down.
Specify the policy regarding duplicated values stored in the list or as hash values (valid only when cargo type is "leaf"). The policy can be "allow" (default), "suppress", "warn" (which offers the possibility to apply a fix), "forbid". Note that duplicates check cannot be performed when the duplicated value is stored: this happens outside of this object. Duplicates can be check only after when the value is read.
Hash ref specifying the cargo held by the hash of list. This has must contain:
Can be "node" or "leaf" (default).
Specifies the type of configuration object held in the hash. Only valid when "cargo" "type" is "node".
Constructor arguments passed to the cargo object. See Config::Model::Node when "cargo->type" is "node". See Config::Model::Value when "cargo->type" is "leaf".
Specify the minimum value (optional, only for hash and for integer index)
Specify the maximum value (optional, only for list or for hash with integer index)
Specify the maximum number of indexes. (hash only, optional, may also be used with string index type)
When set, the default parameter (or set of parameters) are used as default keys hashes and created automatically when the "keys" or "exists" functions are used on an empty hash..

You can use "default_keys => 'foo'", or "default_keys => ['foo', 'bar']".

To perform special set-up on children nodes you can also use

   default_with_init =>  { 'foo' => 'X=Av Y=Bv' ,
                           'bar' => 'Y=Av Z=Cv' }

When the hash contains leaves, you can also use:

   default_with_init => { 'def_1' => 'def_1 stuff' ,
                          'def_2' => 'def_2 stuff' }
Specifies that the keys of the hash are copied from another hash in the configuration tree only when the hash is read for the first time after initial load (i.e. once the configuration files are completely read).

   migrate_keys_from => '- another_hash'
Specifies that the values of the hash (or list) are copied from another hash (or list) in the configuration tree only when the hash (or list) is read for the first time after initial load (i.e. once the configuration files are completely read).

   migrate_values_from => '- another_hash_or_list'
Specifies that the keys of the hash follow the keys of another hash in the configuration tree. In other words, the created hash always has the same keys as the other hash.

   follow_keys_from => '- another_hash'
Specifies authorized keys:

  allow_keys => ['foo','bar','baz']
A bit like the "follow_keys_from" parameters. Except that the hash pointed to by "allow_keys_from" specified the authorized keys for this hash.

  allow_keys_from => '- another_hash'
Keys must match the specified regular expression. For instance:

  allow_keys_matching => '^foo\d\d$'
When set, the default parameter (or set of parameters) are used as keys hashes and created automatically. (valid only for hash elements)

Called with "auto_create_keys => ['foo']", or "auto_create_keys => ['foo', 'bar']".

Issue a warning if the key matches the specified regular expression
Issue a warning unless the key matches the specified regular expression
Specifies the number of elements to create automatically. E.g. "auto_create_ids => 4" initializes the list with 4 undef elements. (valid only for list elements)
convert => [uc | lc ]
The hash key are converted to uppercase (uc) or lowercase (lc).
See ``Warp: dynamic value configuration'' below.

Warp: dynamic value configuration

The Warp functionality enables an HashId or ListId object to change its default settings (e.g. "min_index", "max_index" or "max_nb" parameters) dynamically according to the value of another "Value" object. (See Config::Model::Warper for explanation on warp mechanism)

For instance, with this model:

 $model ->create_config_class 
   name => 'Root',
   => [
       macro => { type => 'leaf',
                  value_type => 'enum',
                  name       => 'macro',
                  choice     => [qw/A B C/],
       warped_hash => { type => 'hash',
                        index_type => 'integer',
                        max_nb     => 3,
                        warp       => {
                                       follow => '- macro',
                                       rules => { A => { max_nb => 1 },
                                                  B => { max_nb => 2 }
                        cargo => { type => 'node',
                                   config_class_name => 'Dummy'

Setting "macro" to "A" means that "warped_hash" can only accept one instance of "Dummy".

Setting "macro" to "B" means that "warped_hash" accepts two instances of "Dummy".

Like other warped class, a HashId or ListId can have multiple warp masters (See ``Warp follow argument'' in Config::Model::Warper:

  warp => { follow => { m1 => '- macro1', 
                        m2 => '- macro2' 
            rules  => [ '$m1 eq "A" and $m2 eq "A2"' => { max_nb => 1},
                        '$m1 eq "A" and $m2 eq "B2"' => { max_nb => 2}

Warp and auto_create_ids or auto_create_keys

When a warp is applied with "auto_create_keys" or "auto_create_ids" parameter, the auto_created items are created if they are not already present. But this warp never removes items that were previously auto created.

For instance, when a tied hash is created with "auto_create => [a,b,c]", the hash contains "(a,b,c)".

Then, once a warp with "auto_create_keys => [c,d,e]" is applied, the hash then contains "(a,b,c,d,e)". The items created by the first auto_create_keys are not removed.

Warp and max_nb

When a warp is applied, the items that do not fit the constraint (e.g. min_index, max_index) are removed.

For the max_nb constraint, an exception is raised if a warp leads to a number of items greater than the max_nb constraint.

Introspection methods

The following methods returns the current value stored in the Id object (as declared in the model unless they were warped):


Returns the object type contained by the hash or list (i.e. returns "cargo -> type").

get_cargo_info( < what > )

Returns more info on the cargo contained by the hash or list. "what" may be "value_type" or any other cargo info stored in the model. Returns undef if the requested info is not provided in the model.


Returns a list (or a list ref) of the current default keys. These keys can be set by the "default_keys" or "default_with_init" parameters or by the other hash pointed by "follow_keys_from" parameter.


Returns the object name. The name finishes with ' id'.


Returns the config_class_name of collected elements. Valid only for collection of nodes.

This method returns undef if "cargo" "type" is not "node".


Returns the number of fixes that can be applied to the current value.

Information management

fetch_with_id ( index => $idx , [ check => 'no' ])

Fetch the collected element held by the hash or list. Index check is 'yes' by default. Can be called with one parameter which is used as index.


Get a value from a directory like path. Parameters are:
Poor man's version of XPath style path. This string is in the form:


Each word between the '/' is either an element name or a hash key or a list index.

Either "default", "custom", "user",... See "mode" parameter in <Config::Model::Value/``fetch( ... )''>
Either "skip", "no"
If the path leads to a leaf, this parameter tell whether to return the stored value or the value object.
Whether to create missing keys
When the hash key used contains '/', (for instance a directory value), the key cannot be used as is with this method. Because '/' is already used to separate configuration items (this is also important with Config::Model::FuseUI). This parameter specifies how the forbidden '/' char is shown in the path. Default is "<slash>"

set( path, value )

Set a value with a directory like path.

copy ( from_index, to_index )

Deep copy an element within the hash or list. If the element contained by the hash or list is a node, all configuration information is copied from one node to another.


Returns an array containing all elements held by the hash or list.

fetch_all_values( mode => ..., check => ...)

Returns an array containing all defined values held by the hash or list. (undefined values are simply discarded). This method is only valid for hash or list containing leaves.

With "mode" parameter, this method returns either:

The value entered by the user
The value entered in preset mode
The value entered in preset mode or checked by default.
The default value (defined by the configuration model)


Returns an array containing all indexes of the hash or list. Hash keys are sorted alphabetically, except for ordered hashed.


Like fetch_all_indexes. This method is polymorphic for all non-leaf objects of the configuration tree.

defined ( index )

Returns true if the value held at "index" is defined.

exists ( index )

Returns true if the value held at "index" exists (i.e the key exists but the value may be undefined). This method may not make sense for list element.


Return true if the array or hash is not empty.

delete ( index )

Delete the "index"ed value


Delete all values (also delete underlying value or node objects).


Delete all values (without deleting underlying value objects).

warning_msg ( [index] )

Returns warnings concerning indexes of this hash. Without parameter, returns a string containing all warnings or undef. With an index, return the warnings concerning this index or undef.


Returns the current number of warning.


Returns the error messages of this object (if any)


Dominique Dumont, ddumont [AT] cpan [DOT] org


Dominique Dumont


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