jolt/host/chez/seed
Dmitri Sotnikov f3084f8043
Collection fns: JVM-faithful return types + laziness (#219)
A type-aware audit (~190 collection expressions vs reference Clojure) found four
divergences the corpus missed — value-equality (= [0 1] '(0 1)) hides type and
laziness differences. Fixed, with type-predicate + over-infinite corpus rows that
pin them.

- partition-all [n coll] built vector chunks; JVM chunks are seqs. (The [n step
  coll] arity was already correct, as is the partition-all transducer, whose
  chunks are vectors in JVM too.) Now builds seq chunks.
- replace always returned a vector (mapv) and was eager; JVM is type-preserving —
  a vector maps to a vector, any other seqable to a lazy seq.
- sequence eagerly realized its source (into-xform), so (first (sequence (map inc)
  (range))) hung. Rewrote as a transformer iterator: pull one input at a time,
  buffer the step outputs, emit lazily, run the completion to flush a stateful
  xform. eduction builds on it (lazy, no longer an eager vector).
- mapcat and (apply concat coll-of-colls) hung over an infinite source because
  jolt-apply seq->lists the trailing arg and mapcat seq->lists the map result.
  Added lazy-concat-seq (lazily flatten a seq of colls); mapcat uses it directly,
  and apply special-cases concat (its result is lazy) to route through it.

Docs: a cross-cutting return-type + laziness contract in docs/spec/09-core-library;
SPEC.md notes that = masks type/laziness so they need predicate / over-infinite
rows. EBNF is reader syntax only — unaffected.

Seed change (partition-all/replace/eduction are clojure.core overlay) -> re-mint;
selfhost holds. make test + shakesmoke + buildsmoke green, 0 new divergences.

Co-authored-by: Yogthos <yogthos@gmail.com>
2026-06-26 03:01:36 +00:00
..
image.ss Collection fns: JVM-faithful return types + laziness (#219) 2026-06-26 03:01:36 +00:00
prelude.ss Collection fns: JVM-faithful return types + laziness (#219) 2026-06-26 03:01:36 +00:00
README.md Docs: Chez-only, drop the Janet-era references and obsolete migration notes 2026-06-22 09:05:35 -04:00

Chez bootstrap seed

These two files are the bootstrap compiler for jolt — the seed that makes the build self-hosting:

  • prelude.ss — the clojure.core prelude (all tiers + clojure.string/walk/ template/edn/set/pprint) as Scheme def-var! forms.
  • image.ss — the compiler image (jolt.ir + jolt.analyzer + jolt.backend-scheme) as Scheme def-var! forms.

Both are generated, not hand-written. They are checked in because a fresh checkout must be able to build jolt-on-Chez using only Chez: host/chez/bootstrap.ss loads this seed, then rebuilds the prelude + image from the .clj/.ss sources via the on-Chez compiler (read → analyze → emit, all on Chez). The seed is a joint byte-fixpoint: rebuilding from an up-to-date seed reproduces it exactly. make selfhost (host/chez/selfcheck.sh) runs host/chez/bootstrap.ss and diffs the rebuilt artifacts against the checked-in seed.

Re-minting

When the seed sources change (the core tiers, the compiler namespaces, the host contract, the reader, emit-image.ss), the seed drifts and make selfhost fails. Re-mint it by running host/chez/bootstrap.ss and writing the freshly rebuilt prelude/image back to host/chez/seed/prelude.ss / host/chez/seed/image.ss, then commit the refreshed files.