Question

I have a ‘hash tree’ like this:

dat = {
    'building' => {'street' => 'High Street 10', 'people' =>[Person, Person]}
}

Person can be whatever.

So, in my code, I directly access ‘building’ like so: dat['building'], now is there a way to somehow go, up the tree, to have access to {'building' => {...}}, again?

I currently have a function that let’s me access either of those:

    def info with_root = false
      with_root ? dat : dat['building']
    end #info

It doesn’t look criminally bad (I think), but I hope there is a nicer way.

Thanks!

Answer 1

Short answer: no.

The reason is this.

Suppose you have:

 addr = {'street' => 'High Street 10', 'people' =>[Person, Person]}
 dat1 = {'building' => addr}
 dat2 = {'zip'=>55117, 'electricBillID'=>11223344, 'address' => addr

What happens when you go “up”? Do you get to dat1 or dat2?

If you really need to be able to do this — and it’s not obvious that you do — you’ll need to use a more complex data structure that includes links to the containing objects — something like a tree (https://rubygems.org/gems/rubytree) or a simple graph structure.

And, as has been mentioned, if you just hang onto the root object, you can always crawl your way back down the hash.