The spine: types ARE posts, and typing is transitive the right way. is-a
(instance-of) does NOT chain on its own, but subsumption does — an instance of a
subtype is an instance of the supertype.
- registry gains "subtype-of" (directed, transitive). host/blog-types-of(slug) =
declared is-a targets PLUS every subtype-of-ancestor of each (composed host-side
over relations/descendants — no new Datalog rules). host/blog-is-a?(slug,type)
is transitive through subtype-of.
- host/blog-seed-types! seeds the root type-posts "type" and "tag" (real posts
that document themselves) with tag subtype-of type, so anything is-a tag is
transitively a type. Idempotent; wired into serve.sh.
- gradual-validation seam: host/blog-type-schemas (empty) + host/blog-schema-of +
host/blog-type-valid? (vacuously true with no schemas) wired into edit-submit
alongside the parse check — enforcement is a one-line add later, not a retrofit.
6 tests: types-of = declared + all subtype-of supertypes; is-a? transitive
through subtype-of; is-a alone does NOT chain; instance of tag is transitively a
type; type-valid vacuous with no schemas. 255/255.
Verified live: /type/ + /tag/ render as posts, tag subtype-of type survived a
recreate (durable), ocaml is-a tag.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
giles
cb2fc788d7