Can someone please share an example of how to use @flow with typescript?

[suparngp]

I am having a bit of a trouble with @flow. I was using flow() wrapper with class properties like createUser = flow(*function()...). Now that @flow is available, I was hoping to convert everything to

@ flow
*createUser(){}

But now, that means I have to specify the correct return type of the function, or else typescript complains. So I tried something like this

@ flow
*createUser(): Generator<unknown, void, Result> {}

and wrapping the using it as following:

const result = await flowResult(instance.createUser(....));
However, result type is void (cuz I wrote it like that in the return type) and I don't know how to make it return a CancellablePromise.

[kubk]

There are a lot of problems with generators in TypeScript. Basically, TypeScript can't infer the type of yield expressions in such simple cases:

const foo = yield 1; // variable foo has type 'any' instead of 'number' 

Here is the open issue: microsoft/TypeScript#32523
Currently, generators in TypeScript aren't type-safe and not very convenient to use. Mobx can't fix that.