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@kutyel
Last active August 5, 2019 20:51
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My own implementation of curry πŸ›
// Ultimate version
const curry = (f, ...args) =>
f.length <= args.length
? f(...args)
: x => curry(f, ...args, x)
@kutyel
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kutyel commented Oct 31, 2017

Awesome 😍 Thanks very much! I just noticed I need the second ...args in the recursive call to curried πŸ˜‰

@kutyel
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kutyel commented Oct 31, 2017

I see what you did there with the default param, very clever! πŸ€“ I was actually looking for a way to return that lambda without the function keyword, and here I have my answer 😊

@rachelcarmena
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rachelcarmena commented Aug 5, 2019

Hi! I'm here because I watched again your talk about Lenses in Lambda World (again = I was there that day πŸ˜‰ ). Congrats for it!
I would like to know what do you think about these concerns:

  • The possibility of calling that function with more than one parameter. For example, a different arity could be passed.
  • The possibility of not having unary functions because of (...argz).

Here I have another version to avoid those things: https://gist.github.com/rachelcarmena/196b9f8b1c6b078b65fb1328f09c0269

What do you think about it? Do you think that my concerns make sense?

Thanks in advance!

@kutyel
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kutyel commented Aug 5, 2019

Hi Rachel! Thanks for the compliments, I'm glad you like the talk! ☺️ I think you are right, what about this implementation?

const curry = (f, ...args) => f.length <= args.length ? f(...args) : x => curry(f, ...args, x)

The argz thing was added by @ericelliott, I don't really remember now why to be honest πŸ˜‚

@rachelcarmena
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Thanks @kutyel! I'd remove all the additional parameters. For example, this situation would be possible:

const sum = (a, b) => a + b;
const curriedSum = curry(sum);
const wrongCurriedSum1 = curry(sum, 2); // a function with one parameter
console.log(wrongCurriedSum1(3)); // 5
const wrongCurriedSum2 = curry(sum, 2, 3); // not a function, but 5
const wrongCurriedSum3 = curry(sum, 2, 3, 4); // not a function, but 5

Thanks again!

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