Hierarchical Family Map

recursive model ownership with parent/depth/path metadata and tree mutation messages

Dark SVG source uses the VMx architecture palette and keeps arrows behind masked component boxes.

Recursive contract

  • Each node owns its model and same-family child nodes.
  • Parent, depth, path, root, and leaf facts are built into the primitive.
  • Cycle protection keeps tree mutation safe.

Materialization

  • Children are lazy unless eager construction is requested.
  • Invalidation and structural changes publish explicit tree messages.
  • Lazy subtrees do not participate in lifecycle until materialized.

Best fit

  • Use it for explorer trees, notebooks, outlines, and taxonomies.
  • Pair with ExpandableState and walk utilities for renderable flattened views.
  • Use CompositeVM only when the domain is a list, not a recursive tree.