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0 pointsbrintnc6y ago0 comments

not sure how i made it through my entire CS degree without learning this term. either that or i just don't remember it. anyways, thank you! this is really useful even outside of Elixir.

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quaunaut6y ago

I've honestly never heard anyone who isn't an Elixir programmer use it. I wouldn't worry about not having heard it before.

grzm6y ago

It's much more common than just Elixir programmers. It's a common concept in computer science, particularly in functional programming or languages which permit function overloading on arguments.

https://en.wikipedia.org/wiki/Arity

Edit to add: I've heard and used arity for at least 10 years, in particular in the Clojure community. I've heard of Elixir and understand it shares some common ideas with Clojure and Ruby, but never been a part of its community.

hopia6y ago

In functional programming classes at the uni you probably wouldn't hear this because if they teach Haskell which I assume most do, every function always takes just one argument. That's because functions are curried by default.

I personally haven't really heard this mentioned anywhere outside of the Erlang/Elixir sphere.

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pmarreck6y ago

I learned about it in the Ruby world.

Also, interestingly, it was available from Javascript 1.2 to 1.4: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...

I think it's a useful name for a useful concept, not sure why they'd take it out, "Function.prototype.length" is a much poorer replacement semantically (but hey, Javascript isn't known for its correctness or well-thought-out design...)

Maultasche6y ago

I had never heard of "arity" either until I started reading about functional programming concepts. It seems to be used a lot within the functional programming world, but not so much outside of that.

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