Function treeNodes

docs/app/js/sanddance-app.js:143069–143072

(name, context)

}
const datum = (d)=>d.data;
function treeNodes(name, context) {
    const tree = data.call(context, name);
    return tree.root && tree.root.lookup || {};
}
function treePath(name, source, target) {
    const nodes = treeNodes(name, this), s = nodes[source], t = nodes[target];
    return s && t ? s.path(t).map(datum) : undefined;