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POnode.js recursive setTimeout() inside of a psuedoclass
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copied!<p>I think I'm having a difficult time wrapping my head around the scope of the following code:</p> <pre><code>var EventEmitter = require('events').EventEmitter, util = require('util'); // Here is the Ticker constructor: var Ticker = function(time) { this.time = time; this.tick = function() { this.emit('tick'); setTimeout(this.tick(), this.time); }; } util.inherits(Ticker, EventEmitter); var newTicker = new Ticker(1000); newTicker.on('tick', function() { console.log("TICK"); }); newTicker.tick(); </code></pre> <p>What ends up happening, is that the "tick" gets called many, many times filling up the stack without the setTimeout actually setting the timeout to one second.</p> <p>Could any explain to me what's going on?</p> <hr> <p><strong>EDIT:</strong> I looked a little bit more, and I still couldn't figure out the issue of scope, really.</p> <p>What I ended up doing was following the solution that was given for the problem, which I tried to solve by way of setTimeout().</p> <p>The solution given was:</p> <pre><code>var EventEmitter = require('events').EventEmitter, util = require('util'); // Here is the Ticker constructor: var Ticker = function(time) { var self = this; this.time = time; setInterval(function() { self.emit('tick'); }, self.time); }; util.inherits(Ticker, EventEmitter); var ticker = new Ticker(1000); ticker.on('tick', function() { console.log("TICK"); }); </code></pre> <p>It does make more sense to me... What I'm wondering now is: Do inner functions and objects in javascript not keep track of their parent's scope and variables?</p>

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