Hey everyone, interfaces in my d.ts files have a _...

# javascript

[John Fields]

Hey everyone, interfaces in my d.ts files have a __doNotUseOrImplementIt property:

interface IFoo {
        bar(): void;
        readonly __doNotUseOrImplementIt: {
            readonly "IFoo": unique symbol;
        };
    }

An implementation without the property obviously doesn't compile. An implementation with the property doesn't compile either. For example this doesn't build:

class Foo implements IFoo {
    bar(): void {
        throw new Error("Method not implemented.");
    }
    readonly __doNotUseOrImplementIt: { readonly foo: unique symbol; };
}

Suggested workarounds in KT-56618 are:
• write a script to remove them (looks like a hack with unknown side effects)
• do expect/actual for any interfaces you want to implement in TS
Has anyone else run into this? Are these truly my best options? Am I just doing something wrong?

[turansky]

You can mark IFoo as external to avoid regular interfaces limitations

[Edoardo Luppi]

I'm currently using a post compile step to remove them.