Cannot reference an object within one of its methods' default arguments

TypeScript Version: 2.0.3

Code

let Obj = {
  get () {},
  set ( value = Obj.get () ) {}
};

Obj.missing (); // Obj is treated as `any`, so I don't get any error for the usage of the undefined method `missing`

Expected behavior:

I expect to get an error for the usage of the undefined method Obj.missing.

Actual behavior:

I don't get any, since if I use Obj within a default argument inside one of Obj's own methods the entire object type becomes any.

Ugly workaround:

let _self;
let Obj = _self = {
  get () {},
  set ( value = _self.get () ) {}
};

Obj.missing (); // I get an error as expected

I expect to get an error for the usage of the undefined method Obj.missing.

you would under --noImplicitAny.

c:\ts>tsc --noImplicitAny a.ts
a.ts(1,5): error TS7022: 'Obj' implicitly has type 'any' because it does not have a type annotation and is referenced directly or indirectly in its own initializer.
a.ts(3,9): error TS7022: 'value' implicitly has type 'any' because it does not have a type annotation and is referenced directly or indirectly in its own initializer.

Why should I be forced to use --noImplicitAny or to write ugly workarounds when it seems clear to me that the problem is that TypeScript should be a little smarter about this particular case?

Maybe I'm wrong about it, but why should this behavior be considered the correct one?

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Cannot reference an object within one of its methods' default arguments #11628

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Cannot reference an object within one of its methods' default arguments #11628

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mhegazy commented on Oct 17, 2016

fabiospampinato commented on Oct 18, 2016

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