How to find code for method?

[Phaser]

What is the best way to find the source code for a method to understand how it works? As sometimes I can't seem to find the documentation in the API or find I need more details... just a silly example that I find difficult... in the examples

game.load.image('menu', 'assets/buttons/number-buttons-90x90.png', 270, 180);

When I look up API it says 

image(key, url, overwrite) 

well clearly 270 and 180 does not correspond to this overwrite boolean parameter... Is this a mistake in the API or how do I find the code to this instance of game.load.image?

[noobshit]

It has to be mistake in examples. Code will work, because:

game.load.image(key, url, overwrite) 
game.load.image('menu', 'assets/buttons/number-buttons-90x90.png', 270, 180);
key = 'menu'; // correct
url = 'assets/buttons/number-buttons-90x90.png'; // correct
overwrite = 270; // 270 in logical expression is true, no problem...
// 180 will be ignored

Javascript... thats the reason I'm using Typescript:

[drhayes]

Here is the documentation site: http://phaser.io/docs/2.5.0/index

The "via" column is a big clue as to what objects are where: anything in that column is available via (get it?) a property on game or, sometimes, on a stage.

In this case, "game.load.image" is a method on the Phaser.Loader: http://phaser.io/docs/2.5.0/Phaser.Loader.html#image

Thus, here is the source code for that method: https://github.com/photonstorm/phaser/blob/32326ae2434fb47d24def0b21ed8b818fbc72f55/src/loader/Loader.js#L693

Often the display object classes use Components, so their methods are in another castle code-wise, but most of the time it's pretty straightforward to find the implementation you're looking for.