/**
* The attribute module provides an augmentable Attribute implementation, which
* adds configurable attributes and attribute change events to the class being
* augmented. It also provides a State class, which is used internally by Attribute,
* but can also be used independently to provide a name/property/value data structure to
* store state.
*
* @module attribute
*/
/**
* The attribute-base submodule provides core attribute handling support, with everything
* aside from complex attribute handling in the provider's constructor.
*
* @module attribute
* @submodule attribute-base
*/
/**
* <p>
* Attribute provides configurable attribute support along with attribute change events. It is designed to be
* augmented on to a host class, and provides the host with the ability to configure attributes to store and retrieve state,
* along with attribute change events.
* </p>
* <p>For example, attributes added to the host can be configured:</p>
* <ul>
* <li>As read only.</li>
* <li>As write once.</li>
* <li>With a setter function, which can be used to manipulate
* values passed to Attribute's <a href="#method_set">set</a> method, before they are stored.</li>
* <li>With a getter function, which can be used to manipulate stored values,
* before they are returned by Attribute's <a href="#method_get">get</a> method.</li>
* <li>With a validator function, to validate values before they are stored.</li>
* </ul>
*
* <p>See the <a href="#method_addAttr">addAttr</a> method, for the complete set of configuration
* options available for attributes.</p>
*
* <p><strong>NOTE:</strong> Most implementations will be better off extending the <a href="Base.html">Base</a> class,
* instead of augmenting Attribute directly. Base augments Attribute and will handle the initial configuration
* of attributes for derived classes, accounting for values passed into the constructor.</p>
*
* @class Attribute
* @param attrs {Object} The attributes to add during construction (passed through to <a href="#method_addAttrs">addAttrs</a>).
* These can also be defined on the constructor being augmented with Attribute by defining the ATTRS property on the constructor.
* @param values {Object} The initial attribute values to apply (passed through to <a href="#method_addAttrs">addAttrs</a>).
* These are not merged/cloned. The caller is responsible for isolating user provided values if required.
* @param lazy {boolean} Whether or not to add attributes lazily (passed through to <a href="#method_addAttrs">addAttrs</a>).
* @uses AttributeCore
* @uses AttributeObservable
* @uses EventTarget
* @uses AttributeExtras
*/
function Attribute() {
Y.AttributeCore.apply(this, arguments);
Y.AttributeObservable.apply(this, arguments);
Y.AttributeExtras.apply(this, arguments);
}
Y.mix(Attribute, Y.AttributeCore, false, null, 1);
Y.mix(Attribute, Y.AttributeExtras, false, null, 1);
// Needs to be `true`, to overwrite methods from AttributeCore
Y.mix(Attribute, Y.AttributeObservable, true, null, 1);
/**
* <p>The value to return from an attribute setter in order to prevent the set from going through.</p>
*
* <p>You can return this value from your setter if you wish to combine validator and setter
* functionality into a single setter function, which either returns the massaged value to be stored or
* AttributeCore.INVALID_VALUE to prevent invalid values from being stored.</p>
*
* @property INVALID_VALUE
* @type Object
* @static
* @final
*/
Attribute.INVALID_VALUE = Y.AttributeCore.INVALID_VALUE;
/**
* The list of properties which can be configured for
* each attribute (e.g. setter, getter, writeOnce etc.).
*
* This property is used internally as a whitelist for faster
* Y.mix operations.
*
* @property _ATTR_CFG
* @type Array
* @static
* @protected
*/
Attribute._ATTR_CFG = Y.AttributeCore._ATTR_CFG.concat(Y.AttributeObservable._ATTR_CFG);
/**
* Utility method to protect an attribute configuration hash, by merging the
* entire object and the individual attr config objects.
*
* @method protectAttrs
* @static
* @param {Object} attrs A hash of attribute to configuration object pairs.
* @return {Object} A protected version of the `attrs` argument.
*/
Attribute.protectAttrs = Y.AttributeCore.protectAttrs;
Y.Attribute = Attribute;
