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Comment by esailija | Hacker News Reader

You can replace

    function(data) { return doSomething(data); }

With

    doSomething

Named functions are just as first-class as anyonymous ones...

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While in most cases you can do that, they are not exactly equivalent. For example, you might be passing the callback to a function that attaches members to it.

But usually you see wrapping done in order to bind methods, like

  f = function(data) { return obj.doSomething(data);}

If you replaced that with

  f = obj.doSomething;

you'd likely have broken code.

A native method for binding methods has existed for a long time and is called just that:

    f = obj.doSomething.bind(obj);

Wrapping functions like in the example is different and is very common among cargo cultists

>A native method for binding methods has existed for a long time and is called just that:

Well, bind is a relatively recent addition. It wasn't added to IE until IE9, and it wasn't added to Safari until March 2012. In any case, I think that

  f = (data) -> obj.doSomething data

is far more readable than

  f = obj.doSomething.bind obj

Edit: it's also worth mentioning that in Chrome and FireFox, at least, the latter version of f is an order of magnitude slower than the former (http://jsperf.com/native-vs-non-native-bind)

But yes, wrapping functions is usually (but not always) silly.

Well, this is more of an example of the syntax. The lambda body might be quite complex.

Right. But I have seen actual code do this plenty of times and there was no explanation in the article so I naturally assumed it was just like those cases where basics of functions are not understood.

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