simon/jolt
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions
jolt/host/chez/seed
History
Yogthos 467ad75ff7 Chez numeric tower: exact ints / Ratio / double for JVM parity (jolt-n6al) 
jolt was all-flonum (one :number type, inherited from Janet whose only number
type is a double). The Chez runtime has a full numeric tower, so the zero-Janet
path now carries it = JVM Clojure semantics:

  (/ 1 2)      => 1/2      (exact Ratio, was 0.5)
  (integer? 3) => true   (integer? 3.0) => false   (float? 3.0) => true
  (ratio? (/ 1 2)) => true   (= 3 3.0) => false   (== 3 3.0) => true
  (+ 1 2) => 3 (exact)   (/ 1.0 2) => 0.5 (double)

jolt= was already exactness-aware (values.ss) and == is value-equality, so
=/== match the JVM split. The reader preserves exactness (integer literals exact,
a/b ratios exact rationals, decimals/exponents flonums); backend_scheme emit-const
renders exact ints/ratios and flonums faithfully; the value-position arithmetic,
count, int, compare, bit ops, parseLong, string .length/.indexOf, range,
timestamps, and array bytes return exact integers (= JVM int/long) instead of
coercing to flonum. double/parseDouble/clojure.math floor|ceil|signum stay double.

Only the zero-Janet path carries the tower (the Janet reader loses exactness into
a double before emit). The prelude/all-flonum path is unaffected for compiled code;
the runtime reader is shared, so a couple of all-flonum reader assertions become
value (==) assertions. ~16 numeric corpus cases now give the JVM tower value vs the
Janet-era :expected and are allowlisted as tower divergences (Chez == reference
JVM) pending the corpus flip to JVM (jolt-ecz0). No BigDecimal type (1M).

Re-minted. zero-janet 2682 (floor 2698->2682, the reclassified tower cases), 0 new
divergences; fixpoint 10/10, bootstrap 6/6, spine 35/35, cli 49/49; Janet gate 155
files 0 failed.
2026-06-20 23:09:27 -04:00
..
image.ss Chez numeric tower: exact ints / Ratio / double for JVM parity (jolt-n6al) 2026-06-20 23:09:27 -04:00
prelude.ss Chez numeric tower: exact ints / Ratio / double for JVM parity (jolt-n6al) 2026-06-20 23:09:27 -04:00
README.md Chez Phase 3 inc9a: self-contained Chez bootstrap (no Janet in the loop) 2026-06-20 06:46:05 -04:00

README.md

Chez bootstrap seed

These two files are the bootstrap compiler for jolt-on-Chez — the seed that makes the build self-hosting with no Janet in the loop:

  • 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 (test/chez/bootstrap-test.janet verifies this).

Janet was used once, historically, to mint the very first seed (the Janet analyzer/ emitter cross-compiled the sources, then the on-Chez compiler iterated to the fixpoint — see test/chez/fixpoint-test.janet). After that, Janet is never needed to build or run jolt-on-Chez.

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 bootstrap-test fails. Re-mint it:

(import host/chez/driver :as d)
(import host/chez/jolt-chez :as jc)
(def ctx (d/make-ctx))
(d/mint-chez-seed* (jc/ensure-prelude ctx)
                   (d/ensure-compiler-image ctx "/tmp/stage1.ss")
                   "host/chez/seed/prelude.ss"
                   "host/chez/seed/image.ss")

Then commit the refreshed prelude.ss / image.ss.