ok.js
function (newValue) {
		var oldValue = this._value;
		if (oldValue !== newValue) {
			this._value = newValue;
			this.trigger(EVENT_CHANGE, this, newValue, oldValue);
		}
	}
function (newValue) {
		var oldValue = this._value;
		if (oldValue !== newValue) {
			this._value = newValue;
			this.trigger(EVENT_CHANGE, this, newValue, oldValue);
		}
	}
function ( newValue ) { var oldValue = this . _value ; if ( oldValue !== newValue ) { this . _value = newValue ; this . trigger ( EVENT_CHANGE , this , newValue , oldValue ) ; } }
Replace the internal property with a new value and trigger a 'change'
@param {*} newValue New property value
@fires change
Replace the internal property with a new value and trigger a change