Two concrete demonstrations of the composition architecture:
THIRD DOMAIN (proves step 8's "a new domain is just a dict + leaf, no new control flow").
host/comp-deps folds a composition to the object ids it TRANSCLUDES — the static contains
DAG of a body. It reuses host/comp-fold's seq/alt/each dispatch verbatim; only the leaf
(collect `(ref ID)`) + accumulator (concat) are new. Useful in its own right (what a
(seq (ref c0) (each … (ref …))) body pulls in; context-specific — alt picks the taken
branch). compose suite 20/20.
LIVE EXECUTE-FOLD DEMO (makes step 7 tangible, parallel to /compose-demo for render).
/workflow-demo runs ONE composition object's :body through host/exec-run — the SAME structure
the render-fold would turn into HTML, folded by execute into a plan of effects (validate →
branch on status → notify each recipient). host/blog-seed-workflow-demo! + host/blog-workflow-
demo + route + serve.sh seed. Shows the behaviour model IS an execute-fold over a composition
object — the same object the block editor authors. blog suite 165/165.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The roadmap's capstone: now that two folds exist (render, execute), extract the machinery
they share. host/comp-fold (compose.sx) is the reusable core — the seq/alt/each combinator
dispatch + the `when` predicate set (host/comp--pred?) + the context-environment + the `each`
source (host/comp--source) + recursion + the depth guard, ALL in one place. A domain plugs in
via a small dict {:empty :combine :leaf :overflow}; only its leaves and how results combine
differ:
render = {:empty "" :combine str …} leaf -> markup (+ row/grid layout combinators)
execute = {:empty (list) :combine concat …} leaf -> effect
host/comp-render and host/exec-run are now one-liners over host/comp-fold with their domain.
execute.sx shed its own seq/alt/each dispatch — it's just a dict + a leaf. A THIRD domain
(eval/reduce/extent over the same algebra) is now only a new dict + leaf, no new control flow.
Both folds went through the core with ZERO behaviour change: new tests/compose.sx exercises
the core + render domain directly (17/17 — leaves, seq, row, alt+when (has/eq/not), each
(items/query/empty), tmpl recursion over a (children) tree + depth guard, ref transclude, one
object two contexts); execute 13/13; blog 162/164 (2 pre-existing relate-picker fails). Full
host conformance 388/390. Wired tests/compose.sx into conformance.
plans/composition-objects.md roadmap steps 1-8 COMPLETE.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
STEP 5 (cards-as-objects). The importer no longer carries a Ghost body as one opaque
sx_content string: host/blog--decompose! splits an (article …) into one stored card OBJECT
per top-level block (is-a the mapped card-type + its field-values), links each by an ordered
`contains` edge, and sets the post :body = (seq (ref c0) (ref c1) …). Card types now carry a
render :template, so the new `ref` combinator (compose.sx) transcludes each card via the
SAME typed-block path articles use. /import wired to decompose; the home index filtered to
published so the "block"-status card objects stay hidden. Added the `val` leaf (raw field
value, no <span>) for attribute interpolation in templates (href/src). The post page renders
the transcluded cards — verified end-to-end (conformance 157/159; the 2 fails are the
pre-existing relate-picker pagination pair, unrelated).
PERF (the conformance-speed fix). host/blog typing — types-of / instances-of / type-defs —
computed the subtype closure via lib/relations descendants/ancestors, and EVERY such call
re-saturates the whole CEK-interpreted Datalog ruleset (~seconds each). Typing is the hottest
path (is-a?/types-of/instances-of run per post, per picker, per render), so this dominated
both the blog suite and live page latency. Now the closure is a host-side BFS over the DIRECT
subtype-of edges (the edge:* KV rows, via host/blog--subtype-closure) — one snapshot per
closure, O(edges), cycle-safe, Datalog-free. Same transitive set (KV == relations for direct
edges, host/blog-relate! writes both), so exact, not approximate. Drops Datalog out of the
typing hot path entirely — speeds conformance AND the live site (/tags etc.).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
An object's `each` source can now be a GRAPH QUERY: `(query is-a TYPE)` resolves to
whatever is-a TYPE *right now* — the list isn't baked into the body, it's the live graph.
The object's `each` IS the query; the render is the run over current data (the unifying
property, now over real data).
compose.sx stays self-contained: the `query` source delegates to a resolver bound in the
render context under "query" — it asks the context for data, never reaching into the graph
itself. The host supplies graph access via host/blog--comp-query (`(query is-a TYPE)` ->
host/blog-instances-of -> full records) injected by host/blog--comp-ctx (auth + resolver);
the post handler renders :body against that context.
Added a `val` leaf — the raw field value with no markup wrapper, for use inside attributes
(href/src). `field` stays span-wrapped for display; `(val :slug)` makes a real link in the
each template. /compose-demo's each is now a live (query is-a compose-item) over two seeded
instances instead of a baked literal list.
Verified end-to-end via a focused harness eval over the full relations+persist+blog stack
(query iterates real instances; clean href via val; empty query -> empty, not an error).
Blog suite 151/153 — the 2 fails ("relate-options load-more sentinel", "related picker
offers all posts") are PRE-EXISTING (clean HEAD is 149/151 with the identical 2 fails, a
relate-picker pagination-boundary issue) and unrelated to composition; my 2 new tests pass.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The cards-as-OBJECTS model (plans/composition-objects.md): an object's :body is a tiny UI
language over content-addressed object refs; the render-fold is its interpreter. Four
combinators — seq (sequence) / row,grid (layout/par) / alt+when (conditional/or) / each
(iteration/loop) — plus field/text/card leaves, ref (transclude), and tmpl (recursion).
The two fundamentals designed IN: (1) recursion via self-referential named templates
(tmpl) + each over (children) + a depth guard — renders trees (verified: a nested type
hierarchy -> [Types[Article][Card[Image][Callout]]]); (2) the context is an extensible
ENVIRONMENT — reads it, extends it (:item, :depth) — so behaviour (Slice 9)
and reactivity (signals) plug in via the context with no new combinators.
and/or/choice fall out of one axis ( on forks) x the container strategy (render-all
vs render-first), so Alt isn't a new node — it's 'first'. The unifying property, proven:
the object's CID is its DEFINITION (query/template/every when-variant); render is the
EXECUTION (which items/branch/context). One object renders two ways by context (anon ->
'Please log in', authed -> 'Members area'). Render-fold and the Slice-9 behaviour interpreter
are the same shape — interpreters over content-addressed objects.
lib/host/compose.sx is self-contained (no blog deps); verified via sx_eval (every combinator
+ a recursive tree + a full composed doc across two contexts). Roadmap: wire :body into
host/blog-render, each-source=graph-query, live context, Lexical->card-objects import, block
editor.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
