Partial Application and Lambda Parameter Syntax for JavaScript

Re:Partial Application and Lambda Parameter Syntax for JavaS... by a-saleh on Wednesday January 31, 2018 @05:09AM (#16272794)

Well usually it would be for something that is useful, like

const greaterThan = x => y => y > x

and then I can do thins like

numbers.filter(greaterThan(10))

because greatherThan(10) is a function (and I hope I did put the correct comparison operator :)

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Re:Partial Application and Lambda Parameter Syntax for JavaS... by masklinn on Wednesday January 31, 2018 @05:20AM (#16272842)

It also works better on languages using free functions than those using method calls e.g. in Haskell you have

    filter :: (a -> Bool) -> [a] -> [a]

so you partially apply to a predicate to get a specific filter condition which you can apply to various contexts e.g.

    over10 = filter (>= 10)

That's why functional languages tend to put the callback first in HoFs, it's usually the more common partial application case.

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