[ramda] Cleanup definitions

[moroine]

• Links to documentation: https://ramdajs.com/docs/
• Link to GitHub or NPM: https://github.com/ramda/ramda
• Type of contribution: fix & refactor

Other notes:

• Change function params to $ReadOnlyArray as ramda does not modify input
• Remove usage of any & Object

Should fix #3561

[moroine]

@AndrewSouthpaw @LoganBarnett could you have a look at it?

[LoganBarnett]

@moroine I think these are good changes. One thing I would stipulate is Ramda functions should accept $ReadOnlyArray and return Array. This allows the consumer to use either type as they like. $ReadOnlyArray is not actually a truly immutable array. Using the type is only a promise that you won’t mutate the array within the context of the type. I’m writing this from a phone, but it’s pretty easy to take a Array and pass it into something that takes a $ReadOnlyArray, and mutate the Array immediately afterwards.

Another reason to type inputs as $ReadOnlyArray and output Array is so any other libraries or even your codebase itself can interop with Ramda.

If you need more examples, we have a few open PRs for Ramda currently that are using this paradigm. I didn’t get a thorough look at the PR yet, but I’m pretty sure one of those covers chain already. I’ll take a look when I get back to my machine.

Regarding the input and output types, does that sound reasonable to you?

[LoganBarnett]

Oh. Looks you’re covering Chain instead of chain. And you are returning Array. That’s what I get for reading a diff from a tiny phone. Disregard my post.

[moroine]

@LoganBarnett nice description of $ReadOnlyArray usage. To add more details on why we should always use ReadOnlyArray as param and Array as the return value is because ramda return a new instance.

Also as a side note, I tried many way to remove deprecated type *, especially in curry definitions but I don't think it's possible. I tried to propose a PR on flowJs which would make this possible but unfortunately I don't think it will be merged facebook/flow#8201 😢

[AndrewSouthpaw]

Nice work! Thanks for the review @LoganBarnett