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Comment by bobbyi | Hacker News Reader

But how would this new syntax work when you want to pass two or more anonymous functions to another function? Or when the anonymous function is not the last argument?

Having anonymous functions only for the situation where you are passing exactly one of them to another function and it is the last argument is much more arbitrary than the current style of always temporarily binding functions to names.

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This style takes care of 90 or 99% of the cases. If you have to pass 2 or more functions, revert to using named functions. The 'there' proposal that I mentioned before allows for arbitrary placement of the anonymous function, IIRC. If not, usage patterns will adjust to the new idiom.

You might say by the same argument that single-line lambda expressions take care of 90 or 99% of cases, and you should revert to using named functions for the rest.

I don't think either is true -- if you have more flexibility in the syntax, you'll do more with it.

The reason for all the discussion over the years is that a single line lambda doesn't cover 90% of the cases. If you think in terms of callbacks, I bet one liner cover less than 10% of the cases.

Python already has a solution for callbacks:

    @reg_callback(button.onclick)
    def callback():
        do_stuff()

Whilst this is more pythonic I personally prefer Javascripts use of lambdas as more than a means of expression. More like a way of life for the language :-) And that is IMHO what makes it functionally closer to Scheme. Just looking at the way one defines lambdas in Javascript and their use throughout the language is a thing of beauty.

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