Sub-domains

[nhunzaker]

I think it's time that we have an actual class to describe Domains. We could use this to manage Sub-domains, which could operate relative to the key a Domain is mounted to:

class Network extends Domain {

    setup (repo) {
        this.addDomain('nodes', Nodes) // mounted to ['network', 'nodes']
        this.addDomain('edges', Edges) // mounted to ['network','edges']
    }    

}

repo.addDomain('network', Network)

Outstanding questions:

1. Do parent domains handle actions first, or after all subdomains have completed?

[nhunzaker]

I think I've got this wrong. Let's keep domains simple. Right now they don't implement any introspective methods.

Instead, let's make it so that a Microcosm can mount other Microcosms at a given key path.

[greypants]

iiiiiiiiiiiiiiiiiiiiiiiiiiiinteresting. Sorta like the initial idea. Would definitely help me break up my giant graph domain, which manages nodes, edges, loading state, ui, and some other stuff.

My gut says that children should finish their work first, then parents.

[nhunzaker]

Closing this out again. Sub-domains work well when the state tree is highly nested, but I think domains probably need to stay flat. Nesting largely is necessary for convenience of access, which we can fix by adding a querying API.