Accessing oneof dynamically

Hi,

I can’t find a way nice way to access a oneof property type dynamically, maybe you can advise

Imagine I have the following one of type:

export interface Task_Payload {

    payload: {
        oneofKind: "renameTask";
        renameTask: RenameTask;
    } | {
        oneofKind: "noop";
        noop: NoopTask;
    } | {
        oneofKind: "trimming";
        trimming: TrimmingTask;
    } | {
        oneofKind: undefined;
    };
}

I want to be able to access the type of whatever object has been received

const kind = type.payload.oneofKind;

if (!kind) {
  throw new Error("No kind specified");
}

// it should be of the correct type or at least a 
// union of RenameTask|TrimmingTask|NoopTask
const oneOfKind = type.payload[kind]; 

// The above doesn't work.
}

with the current type definition I’ll have to hard code each possible variant where i’d just like to store the value as is.

Any workaround for this still being type safe?

[timostamm]

Thank you for looking into this so thoroughly, @jcready.

We already have isOneofGroup(). I’ve added getOneofValue(), setOneofValue() and clearOneofValue().

They may be helpful in some obscure situations.

[timostamm]

Yes, but doing this in the runtime is preferable because of less overall code size.