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Re: Beginner's question: How does this function definition work?

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On Mon, 10 Nov 2014 21:54:50 -0800 (PST)
twgray2007@gmail.com wrote:

>   "init" : function init(x, y, settings) {
>             this.value = 1000;
>             this.parent(x, y, settings);
>   }
> 
> I just don't get it. I know : is equivalent to '='., so is it same as:
> 
> var init = function(x, y, settings) ?
> 

In this case : is used only when defining a property in an object literal. This is often used with functions when creating a prototype object, e.g.:

	Thing.prototype = {
		init: function() {
			/* ... */
		}
	};

Using = assigns the function value to a variable, rather than as a property of an object.

If defining a function with a colon not in an object literal doesn't produce an error, then it is actually getting parsed as a label, which is an unrelated, obscure feature of the language having to do with switch statements.

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Thread

Beginner's question:  How does this function definition work? twgray2007@gmail.com - 2014-11-10 21:54 -0800
  Re: Beginner's question:  How does this function definition work? Charles Lehner <est.cel@celehner.com> - 2014-11-11 22:26 -0500
    Re: Beginner's question:  How does this function definition work? RobG <rgqld@iinet.net.au> - 2014-12-09 23:15 +1000
      Re: Beginner's question:  How does this function definition work? cezary.tomczyk@gmail.com - 2014-12-09 13:43 -0800
    Re: Beginner's question:  How does this function definition work? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-12-09 17:59 +0100

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