It's enough to implement one way only. 

In my opinion, `--nodejs --harmony` is nicer than `--nodejs=--harmony`.

What is the difficult part about implementing `--nodejs --harmony`? If yargs parses `--harmony` as another flag instead (not as a value for `--nodejs`), then perhaps node-debug can pre-process `process.argv` before passing it to yargs? Here is the idea:

```js
var args = [];
var nodeArgs = [];
for (var i=0; i<process.args.length; i++) {
  if (process.args[i] === '--nodejs') {
    i++;
   if (process.args[i]) // handle missing value for --nodejs
     nodeArgs.push(process.args[i]);
  } else {
    args.push(process.args[i]);
  }
}

yargs.parse(args);
```