Answer:9 function pipe

[LMFinney]

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[LMFinney]

Getting this basic function was the easy part. When I saw that type safety was required, I hoped there was a way to use https://www.typescriptlang.org/docs/handbook/utility-types.html#parameterstype to handle this, but nope. Ugh.

[tomalaforge]

ouch, lots of function override.

You can do shorter 😅

[LMFinney]

I saw your solution had one less override (resorting to any[] earlier). Is that what you mean? Or another idea?

[tomalaforge]

export class WrapFnPipe implements PipeTransform {
  transform<R, F extends (...args: any[]) => R>(
    func: F,
    ...args: Parameters<F>
  ): R {
    return func(...args);
  }
}

[LMFinney]

Yeah, but that loses all type-safety, right? I think I had that at first, but thought we were supposed to impose type safety.

[tomalaforge]

You have type safety with that, I need to retry it, but I'm sure you have it.

[LMFinney]

I tried it, and you're right. There were two parts I didn't catch when I just read your comment:

1. Using Parameters<F> is the key - it infers the args, and I missed that.
2. The args have to be any[] instead of unknown[]. Using unknown causes a compilation error. I wouldn't have predicted that.

Thanks

[LMFinney]

Actually, never[] also works, and linting doesn't mind that.

[github-actions]

This pull request is stale because it has been open for 15 days with no activity.