Question: compose and assoc to build a structure

[xeob]

Hi folks, this is a question rather than an issue. I'm somewhat new to the wonders of ramda and TypeScript and I might have a naive question here, so please bear with me 😉

I'm trying to build an object that matches a given interface through compose and mutliple assocs, something like

interface SomeStruct {
  a: number[];
  b: string[];
  c: { [index: string]: string };
}

const x: SomeStruct = {
  'a': [],
  'b': [],
  'c': {},
};

const fun = (y: SomeStruct): SomeStruct => {
  return compose(
    assoc('a', [1, 2, 3]),
    assoc('b', ['a', 'b', 'c']),
    assoc('c', { 'k': 'v'})
  )(y);
};

fun(x);

Doing this, I'm getting a following error:

error TS2322: Type '{ prop: number[]; } & {}' is not assignable to type 'SomeStruct'.
Property 'a' is missing in type '{ prop: number[]; } & {}'

The effective and intermediate structure of x matches the SomeType at all steps of this function application. Is there some way around it besides using as any after compose? Am I missing something pretty basic here?

---

Edit: Sorry, now I see it might be related to #90

[wclr]

{ prop: number[]; } is wrong, assoc has really not working typings, should be fixed.

[KiaraGrouwstra]

If this turns out not be a duplicate when #90 is resolved, let's reopen.

[KiaraGrouwstra]

So I fixed #90; guess what, your test isn't passing yet. So reopening until your test passes, as promised. :)

[KiaraGrouwstra]

Well, now we know. This wasn't an assoc issue, but a composition one.

It stems from interaction between composition and functions with generics. Threads #92 and #86 appeared to be about the same problem. I currently intend to track this issue in #78, about currying rather than composition but otherwise seemingly the same issue.

Sorry you're getting bounced to yet another thread again. I'm slowly discovering most outstanding issues are highly related though, so hopefully if I can figure this out we'll have solved everything in one go.

[xeob]

No worries @tycho01. Thanks a lot for the time you've put into looking into that!