Traversing Goodness

visitor-dev.js

var tree = {
  id: null,
  children: [
    {
      id: null,
      children: [
        {
          id: null,
          children:[
            {
              id: null,
              children: [
                {
                  id: null,
                  children: [
                    {
                      id: 1,
                      children: []
                    }
                  ]
                }
              ]
            }
          ]
        }
      ]
    }
  ]
};

function _(what,node){
  return !!node && node.id === what ? node : (
    node && node.children &&
    _(what, node.children.shift())
  )
};

console.log(_(1, tree));

visitor.js

function _(a,b){return!!b&&b.id===a?b:b&&b.children&&_(a,b.children.shift())}