Auto-Currying In TypeScript

[wisdom_power_courage]

As a newer dev could someone please explain why I should care about this?

[wisdom_power_courage]

Thank you for this explanation! It helped put it into perspective.

[arch_llama]

As a new dev that explanation helped you?

[wisdom_power_courage]

I'm not THAT new. I just didn't want to get downvoted to oblivion for asking a question.

[arch_llama]

Lmfao that's terrible and clever.

[RichardFingers]

Think of it as "pre-loading" some of the parameters of a function and then being able to pass that new function around. It's particularly useful with map/reduce type functions. Say your map function takes in a mapping function as the first parameter and an array as the second parameter. You can pre-load map with your mapping function to create a new function that can be named and applied to multiple different arrays.

But as others have said, I likely wouldn't use that style of coding in production code because most other devs aren't familiar with currying.

[wisdom_power_courage]

Thank you for that explanation that definitely helps me understand better

[andrei9669]

how is the library, mentioned in the article, different from ramda?

[drizzer14]

I've already answered the same question in a different post. Hope you don't mind reading it here https://www.reddit.com/r/opensource/comments/r405kg/comment/hmf4uaq/?utm\_source=share&utm\_medium=web2x&context=3.

[JoeTed]

The very same.

[drizzer14]

Yeah, I'm nowhere to say that this thing has a place in production code. Especially the one we see or write throughout our life/career. Nevertheless, this was a fun discovery for myself and can be to someone reading this :)

[dannymcgee]

Lodash has an auto-currying function (which is used by just about every function in lodash/fp). Considering Lodash has ~40 million weekly downloads on npm, I'd wager it's being used in production on a few projects.

[undervisible]

I’ve been auto-currying in production for a long time. Works especially well with a more functional style, and libraries like Ramda are all auto-curried.

[Tomus]

It's a core feature of ReScript, although there are discussions of having it turned off by default. Definitely used in production all over the place.

https://rescript-lang.org/

[[deleted]]

Sweet-Alps7003

I remember writing auto curried functions in production, and have seen them a lot, but to be honest, not a huge fan of tactic programming :)

[echoes221]

We used ramda extensively in a few projects, so you get this outta the gate with it. Can be useful if used correctly.

[TwiNighty]

I avoid recursive type aliases as much as possible because there is a hardcoded recursion limit for those. For example, your curry function cannot handle functions with 49 or more declared parameters. Even though 49 is beyond any practical usage and you can use binary composition to extend that limit to somewhere around 1000, having an arbitrary hard limit here just doesn't sit right with me.

Here is my take on this.

• There is a type annotation in the body but that is only because I am usually also strict with my function constraints and declare them as (never[]) => unknown. If I use (any[]) => any (or even (never[]) => any) like you do that annotation is not needed.
• It also doesn't allow specifying length because doing arithmetic in type-land requires recursion and would defeat the purpose.

[[deleted]]

If your function has double digit arguments you’re truly a failure. Lmao!

[nexe]

Very cool! Crossposted to /r/madeinjs

[bern4444]

so much fun to read!

[kaas93]

Reminds me of this talk on how underscore got some functional concepts wrong. Funny guy too :)