Heterogeneous `combine` typing

Hi. With my understanding, only typing stops combine currently from working with heterogeneous Results, implementation looks ready for them. I just prepared types for combine that works for Result of many types, at least in my tests. Could it be useful for the library?

It will only works for TS 4.0+.

declare function combine<T extends Result<unknown, unknown>[]>(
    resultList: [...T]
  ): CombineResult<T, T>;


type CombineResult<T extends unknown[], U extends unknown[]> = T extends [
  infer Element,
  ...(infer Rest)
]
  ? Element extends Err<unknown, infer ErrH>
    ? Element
    : CombineResult<Rest, U>
  : Ok<
      { [Index in keyof U]: U[Index] extends Ok<infer OkElement, unknown> ? OkElement : never },
      unknown
    >;

[supermacro]

So this approach did indeed work. Check out the implementation based on the most recent commit to the project:

https://github.com/supermacro/neverthrow/blob/cfd12a9af796b11426f9426fa94795912f103b77/src/utils.ts

---

I am going to continue working on neverthrow stuff and then post a release once I am done (end of day today).

Also I will keep this issue open to accept feedback on the current implementation on heterogeneous types.

[supermacro]

Closing this issue, but as always feel free to open a new issue if there’s something you want to discuss / improve / provide feedback on!