Calling a function on each object after denormalization

I have the need to call a function objects, including nested objects, after they've been denormalized. Since it includes nested entities, if I waited until the entire object was denormalized I'd have to re-traverse all of the nested schemas manually, which I'd like to avoid.

To give more context of my specific use-case, I'm storing raw data in a normalized store and I need to instantiate classes from these object on the way out.

I think it would be a fairly simple/straightforward change to the denormalizeObject function:

function denormalizeObject(obj, entities, schema, bag) {
  let denormalized = obj

  Object.keys(schema)
    .filter(attribute => attribute.substring(0, 1) !== '_')
    .filter(attribute => typeof getIn(obj, [attribute]) !== 'undefined')
    .forEach(attribute => {

      const item = getIn(obj, [attribute]);
      const itemSchema = getIn(schema, [attribute]);

      denormalized = setIn(denormalized, [attribute], denormalize(item, entities, itemSchema, bag));
    });

  // New line
  const { transform = _.identity } = bag

  return transform(denormalized);
}

The one issue that I see is that the bag field is the last argument to denormalize. I think just passing the transform key directly there should be fine but there's a non-zero chance it would collide with a key during denormalization if that happened to be a string key. Super edge-case IMHO, but we could either make that key more specific (e.g. transformObject) or prefix it with a _ (e.g. _transform or _transformObject) if you think that's an issue.

Let me know if this makes sense and I can put together a PR with specs.