[protobuf] How to set some mutual exclusion objects in a message

[Ann Lin]

Hello:

I'm a Typescript developer and trying to use protobuf between Typescript 
and Python.

I have to translate several Typescripts interface below to proto3 messages:

```typescript
enum CommandType {
    'Run',
    'Sleep',
    'Read'
}

interface RunCommand {
    commandType: CommandType.Run;
    destination: string;
}

interface SleepCommand {
    commandType: CommandType.Sleep;
    time: number;
}

interface ReadCommand {
    commandType: CommandType.Read;
    book: string
}

type Command = RunCommand | SleepCommand | EatCommand;
```

Tye type `Command` is a message in my .proto like:

```proto3
syntax = "proto3"

enum CommandType {
    RUN = 0;
    SLEEP = 1;
    READ = 2;
}

message Command {
    CommandType commandType = 0;
    ...
}
```

How can I set the rest properties of the message `Command`?

-- 
You received this message because you are subscribed to the Google Groups 
"Protocol Buffers" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to protobuf+unsubscr...@googlegroups.com.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/protobuf/d2198b18-a8c1-4446-a7b6-7b1c0ca3a0a6n%40googlegroups.com.