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POjavascript apply on constructor, throwing "malformed formal parameter"
 

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    <p>thanks to wonderful responses to <a href="https://stackoverflow.com/questions/1959040/possible-to-send-javascript-varargs">this question</a> I understand how to call javascript functions with varargs.</p> <p>now I'm looking to use <strong>apply with a constructor</strong></p> <p>I found some interesting information <a href="https://stackoverflow.com/questions/181348/instantiating-a-javascript-object-by-calling-prototype-constructor-apply">on this post</a>.</p> <p>but my code is throwing errors</p> <p>attempt 1:</p> <pre><code>var mid_parser = new Parser.apply(null, mid_patterns); </code></pre> <p>error:</p> <pre><code>TypeError: Function.prototype.apply called on incompatible [object Object] </code></pre> <p>attempt 2: attempt 1:</p> <pre><code>var mid_parser = new Parser.prototype.apply(null, mid_patterns); </code></pre> <p>error:</p> <pre><code>TypeError: Function.prototype.apply called on incompatible [object Object] </code></pre> <p>attempt 2:</p> <pre><code>function Parser() { this.comparemanager = new CompareManager(arguments); } mid_patterns = [objA,objB,objC] var mid_parser = new Parser(); Parser.constructor.apply(mid_parser, mid_patterns); </code></pre> <p>error:</p> <pre><code>syntax_model.js:91: SyntaxError: malformed formal parameter </code></pre> <p>attempt 3:</p> <pre><code>var mid_parser = Parser.apply(null, mid_patterns); </code></pre> <p>error :</p> <pre><code>TypeError: this.init is undefined // init is a function of Parser.prototype </code></pre> <p>I have a workaround for the time being:</p> <pre><code>function Parser() { if(arguments.length) this.init.call(this,arguments); // call init only if arguments } Parser.prototype = { //... init: function() { this.comparemanager = new CompareManager(arguments); } //... } var normal parser = new Parser(objA,objB,objC); mid_patterns = [objA,objB,objC] var dyn_parser = new Parser(); dyn_parser.init.apply(dyn_parser, mid_patterns); </code></pre> <p>this works pretty well, but it's not as clean and universal as I'd like.</p> <p>is it possible in javascript to call a constructor with varargs?</p>
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