Error message at a constant or a read-only property could be more specific

[ghost]

TypeScript Version: 3.2.0-dev.20181101

Code

const isMutable = false;
isMutable = true;

Expected behavior:

Cannot assign to 'isMutable' because it is a constant.

Actual behavior:

Cannot assign to 'isMutable' because it is a constant or a read-only property. It's obviously not a property, and the compiler should be able to tell this. Note this is more tricky with namespace N { export const x = 0; }, which is also a property, but I think calling it just "a constant" in that case is fine.

[a-tarasyuk]

@Andy-MS What about the following case?

Array = [];

Which error message is correct?

Cannot assign to 'Array' because it is a constant.

or

Cannot assign to 'Array' because it is a constant or a read-only property.

[ghost]

That's declared as declare const Array: ArrayConstructor; so it should be the former case ("because it is a constant.").

[DanielRosenwasser]

Thanks @a-tarasyuk!