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This method can be overridden to return a cached instance.</p> </section> </section> <section class="on-this-page-table"> </section> <section class="title-footer"> <ul class="title-links">  <li><a href="//github.com/canjs/can-construct/tree/v3.0.3/can-construct.js#L208">source</a></li>   </ul> </section> <div class="signature"> <h2 class="signature-title"> <code>Construct.newInstance([...args])</code> </h2> <div class="parameters"> <h3 class="parameters-title">Parameters</h3> <ol> <li><b>args</b> <code>{*}</code>: <p>arguments that get passed to <a href="can-construct.prototype.setup.html" title="">setup</a> and <a href="can-construct.prototype.init.html" title="Called when a new instance of a Construct is created.">init</a>. Note that if <a href="can-construct.prototype.setup.html" title="">setup</a> returns an array, those arguments will be passed to <a href="can-construct.prototype.init.html" title="Called when a new instance of a Construct is created.">init</a> instead.</p> </li> </ol> </div> <div class="returns"> <h3 class="returns-title">Returns</h3> <p> <code>{class}</code>: <p>instance of the class</p> </p> </div> </div> <section class="body"> <p>Creates a new instance of the constructor function. This method is useful for creating new instances with arbitrary parameters. Typically, however, you will simply want to call the constructor with the <strong>new</strong> operator.</p> <h2>Example</h2> <p>The following creates a <code>Person</code> Construct and overrides <code>newInstance</code> to cache all instances of Person to prevent duplication. If the properties of a new Person match an existing one it will return a reference to the previously created object, otherwise it returns a new object entirely.</p> <pre><code class="language-js">// define and create the Person constructor var Person = Construct.extend({ init : function(first, middle, last) { this.first = first; this.middle = middle; this.last = last; } }); // store a reference to the original newInstance function var _newInstance = Person.newInstance; // override Person's newInstance function Person.newInstance = function() { // if cache does not exist make it an new object this.__cache = this.__cache || {}; // id is a stingified version of the passed arguments var id = JSON.stringify(arguments); // look in the cache to see if the object already exists var cachedInst = this.__cache[id]; if(cachedInst) { return cachedInst; } //otherwise call the original newInstance function and return a new instance of Person. var newInst = _newInstance.apply(this, arguments); this.__cache[id] = newInst; return newInst; }; // create two instances with the same arguments var justin = new Person('Justin', 'Barry', 'Meyer'), brian = new Person('Justin', 'Barry', 'Meyer'); console.log(justin === brian); // true - both are references to the same instance </code></pre> </section> <script type="text/javascript"> var docObject = {"type":"function","name":"can-construct.newInstance","parent":"can-construct.static","src":{"line":208,"codeLine":273,"path":"node_modules/can-construct/can-construct.js"},"description":"Returns an instance of `Construct`. 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