Generic type inference failure when multiple type provided (with typescript)

[kwonoj]

Writing below code via ES5 with commonjs,

Rx.Observable.of(1, 'a').subscribe(console.log);

will be executed with below results

1
a

though some editors might complain by type inference failure.

if same code is written in typescript, now those complaint becomes build time failure

error TS2453: The type argument for type parameter 'T' cannot be inferred from the usage. Consider specifying the type arguments explicitly.
Type argument candidate 'number' is not a valid type argument because it is not a supertype of candidate 'string'.

Somewhat related to issue #581, not directly though.

[kwonoj]

I'm looking into this to try resolve.

[kwonoj]

Course caller can explicitly cast like
Rx.Observable.of(<any>1,<any>'a').subscribe(console.log);
, but seems bit hassle.

[staltz]

Can you write Rx.Observable.of<any>(1, a').subscribe(console.log); instead?

[kwonoj]

Yes, that works too. Snippet I took is exaggerated examples of casting hassle. Still it'd be better wouldn't require explicit casting, not sure if it's achievable along with generic based type-safety.

[roganov]

I don't think that Rx.Observable.of<any>(1, 'a') is a hassle, IMO it's perfectly reasonable TypeScript. It also makes you think whether you really want to mix types.

[kwonoj]

Ok, closing now.