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.
Two Chez reader bugs, both JVM-parity gaps:
inc'/+'/foo' (trailing apostrophe) were mis-read as a symbol followed by a
quote macro, because the reader treated ' as a terminator. In Clojure ' is a
NON-terminating macro char (constituent after the first char). Since the seed
is minted on Chez, (def inc' inc) became (def inc 'inc), clobbering inc's var
cell with its own symbol -- so (var-get (var inc)) returned the symbol, not the
fn. Drop ' from the token terminator set; a leading ' still quotes.
^bytes [b] / ^String [x y] return-type hints: the Chez reader lowered ^meta on
a collection to a (with-meta vec meta) form, but emitted a QUALIFIED
clojure.core/with-meta while the Janet reader emits a bare with-meta -- so the
fn/defn macros' unwrap logic (matching the bare head) slipped past it and choked
on a non-vector arglist. Emit bare with-meta to match Janet, and unwrap a
(with-meta <vec> _) arglist in analyze-fn as a backstop.
Re-minted the seed. zero-janet 2699, prelude 2652, Janet gate 155/0, fixpoint
10/10, bootstrap 6/6, all 0 new divergences.
Reader gaps the Chez-hosted analyzer hit where the Janet reader didn't:
- ##Inf / ##-Inf / ##NaN symbolic literals (## dispatch -> flonum).
- #(...) anonymous fn shorthand -> (fn* [p__N#] body), with % / %N / %& and the
max-positional arity rule; scans + rewrites list/vector/set/map bodies.
- #?(...) reader conditional: feature set {:jolt :default}, first matching clause
wins. #?@ splicing not yet supported (one niche case allowlisted).
- (ns name (:require [a :as x])) — the require pre-scan now also reads aliases
from an ns form's :require/:use clauses, not just bare (require ...).
Zero-Janet corpus parity 2240 -> 2288, 0 divergences (2 now-reachable cases
allowlisted: str of Infinity inside a collection — same as the prelude gate —
and #?@ splice). spine-test 35/35; prelude parity 2295 unchanged, 0 new
divergences.
Point the Chez-HOSTED analyzer at the full parity corpus (read -> analyze ->
emit -> eval, all on Chez, no Janet) and close the divergences so the
self-hosted compiler is faithful: 0 divergences, 2159/2494 pass.
Keystone: the on-Chez emitter ran with prelude-mode off, so every call to a
non-native clojure.core fn tripped the "unsupported stdlib fn" out-of-subset
guard. The zero-Janet spine always has the full prelude loaded, so turn
prelude mode on in compile-eval.ss (22% -> 84% pass on a sample).
Faithfulness fixes (each was the Chez host/reader diverging from the Janet
analyzer; fixed in the keeper, not the seed):
- emit-const read a char's codepoint via (get v :ch) — the Janet rep; on Chez a
char is native. Route through a new form-char-code host-contract fn (41 cases).
- next over a lazy seq returned the empty-list terminator (truthy), not nil, so
butlast and other (if (next s) ...) loops ran one step too far — broke
some->/some->>/cond->>.
- reader: radix literals (2r1010/16rFF/36rZ), #^ deprecated metadata, ^meta on
collections (lowers to a runtime with-meta form like the Janet reader),
map-literal source order (values eval left-to-right), and nested syntax-quote
over a literal collapses at read time.
- keyword "a/b" splits into ns/name like the seed (destructure {:keys [x/y]}).
- form-syntax-quote-lower implemented on Chez (was a throwing stub).
7 divergences allowlisted: the same print-method-multimethod / host-class set
the prelude gate defers. 328 crashes remain = shared runtime breadth (host
interop, missing core fns, eval/load-string) deferred to Phase 4 / jolt-r8ku,
not compiler faithfulness.
Gate + speedup: test/chez/run-corpus-zero-janet.janet (floor 2159). Its batched
runner (driver/eval-corpus-zero-janet) runs every case in ONE chez process —
load the runtime once, guard + reset the user namespace per case — instead of a
fresh process per case: 1379s -> 1.6s.
spine-test 35/35; Janet gate 151/0; prelude parity 2295/2494 unchanged, 0 new
divergences.
Chez-side recursive-descent Clojure reader (host/chez/reader.ss) producing the
same jolt forms the Janet reader yields, behind the read-string / __parse-next /
__read-tagged seams the seed registers in eval_runtime.janet. That lights up the
whole *in* read family — read, read+string, with-in-str (read) — plus read-string
and read-string metadata, none of which needed an analyzer change (read-string is
a clojure.core seam, jolt-nil on the prelude until now).
Reader output is pinned to the Janet reader's shapes: numbers coerce to flonum
(the all-double model emit-const uses, else a read int isn't = a source int),
sets read as the {:jolt/type :jolt/set :value [...]} FORM, #tag/#inst/#uuid/#regex
as tagged forms (no data reader applied — read-string never evaluates), ^meta on
a symbol, and the ' ` ~ ~@ @ reader macros. clojure.edn is added to the prelude
tier; its edn->value builds the real set/tagged values and __read-tagged reuses
the inc X #inst/#uuid constructors. The reader-arity edn/read stays a lazy gap
(drain-reader is Janet-coupled) — read-string is the live path.
eval / load-string / runtime defmacro are still out: they need the compiler at
runtime, which is Phase 3 (self-host). Chez-only change, no Janet gate.
Parity 2238 -> 2259, 0 new divergences. _reader 47/47; all chez unit tests green;
emit-test 331/331.
