obj.has() or arr.upsert()

[macmillen]

I often find myself having a field that is optional and wanting to set data on that field. But to do that I first need to check if that field exists and for that I currently convert the node to a view() and then I check if it exists before initializing the field. See this example:

if (!("children" in node.view())) node.set({ children: [] });
node.arr("children").ins(0, blocks);

It would be great if there was a has() operation on the ObjApi. Another idea could be maybe to have something like an upsert() operation:

Option 1:

if (!(node.has("children")) node.set({ children: [] });

Option 2:

node.arr("children").upsert(0, blocks)

Option 2 would already fail when trying to access the prop with .arr("children") so it would need to be a different API.