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POIs it possible to call function.apply without changing the context?
 

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  1. POIs it possible to call function.apply without changing the context?
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    <p>In some Javascript code (node.js specifically), I need to call a function with an unknown set of arguments without changing the context. For example:</p> <pre><code>function fn() { var args = Array.prototype.slice.call(arguments); otherFn.apply(this, args); } </code></pre> <p>The problem in the above is that when I call <code>apply</code>, I'm change the context by passing <code>this</code> as the first argument. I'd like to pass <code>args</code> to the function being called <strong>without</strong> changing the context of the function being called. I essentially want to do this:</p> <pre><code>function fn() { var args = Array.prototype.slice.call(arguments); otherFn.apply(&lt;otherFn's original context&gt;, args); } </code></pre> <p><strong>Edit:</strong> Adding more detail regarding my specific question. I am creating a Client class that contains a socket (socket.io) object among other info pertaining to a connection. I am exposing the socket's event listeners via the client object itself.</p> <pre><code>class Client constructor: (socket) -&gt; @socket = socket @avatar = socket.handshake.avatar @listeners = {} addListener: (name, handler) -&gt; @listeners[name] ||= {} @listeners[name][handler.clientListenerId] = wrapper = =&gt; # append client object as the first argument before passing to handler args = Array.prototype.slice.call(arguments) args.unshift(this) handler.apply(this, args) # &lt;---- HANDLER'S CONTEXT IS CHANGING HERE :( @socket.addListener(name, wrapper) removeListener: (name, handler) -&gt; try obj = @listeners[name] @socket.removeListener(obj[handler.clientListenerId]) delete obj[handler.clientListenerId] </code></pre> <p>Note that <code>clientListenerId</code> is a custom unique identifier property that is essentially the same as <a href="https://stackoverflow.com/a/7579956/107277">the answer found here</a>.</p>
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    1. USMatt Huggins
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    1. COAre you asking how to get a reference to the global context?
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    2. COHave you tried leaving the first argument empty? as long as it's not a required argument, that should work.
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    3. CO@SLaks - no, because `otherFn` will belong to another object, but that object will vary depending on when `fn` is being called.
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      1. USMatt Huggins
 

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