Brings up the seq layer on the Chez runtime. host/chez/seq.ss adds one
lazy-capable node (cseq) that models Clojure's list, cons, and lazy seq -
all print as (...), all sequential-= to each other and to vectors. seq
coerces any seqable (vector/map/set/string/list/seq/nil) to a cseq or nil;
the empty seq is a distinct value printing () (rest of a 1-elem coll is ()
not nil, seq of empty is nil). Leaf ops: first/rest/next/seq/cons/list,
reverse/last, map/filter/remove/reduce/into, range/take/drop/concat/apply,
keys/vals, plus nth/peek/pop extended over seqs. map/filter/reduce apply
their fn arg through jolt-invoke, so a procedure, keyword, or collection all
work as the fn.
Dynamic IFn dispatch: a keyword/vector/coll held in a local (let binding or
fn param) and called as a fn now routes through the jolt-invoke fallback
(procedure? -> apply; keyword/coll -> lookup). The emitter only routes a
:local callee that isn't a known procedure - a named fn's self-recursion
name stays a direct call, so the fib hot path is untouched. Closes the 3
ex-known IFn divergences.
emit.janet: seq/pred ops added to native-ops with arity gates; value-position
clojure.core refs resolve to the RT procedure (native-ops names one for each),
with +/-/*// routed to flonum-coercing wrappers so higher-order arithmetic
((reduce + [])) keeps the all-double model. values.ss: cross-type sequential
=/hash so a vector and a list of the same elements are jolt= and hash alike.
rt.ss: printer learns seqs; top-level nil prints as the empty string (jolt -e
str-style). Fixed latent bug: (conj nil ...) now builds a list, not a vector.
Gates: emit-test 69/69 (fib/mandelbrot/collections/seq/IFn parity vs the jolt
oracle, fib(30) ~24ms unchanged). Subset probe 433/436 -> 595/595 compiled,
0 divergences (was 3 known), 2060/2655 out of subset. Full run-tests green
(125 files, conformance + suites included).
Broaden the Scheme back end past the numeric/functional subset to vectors,
maps, and sets. host/chez/collections.ss adds a copy-on-write persistent
vector and a bitmap HAMT (the structure 0c measured self-hostable) backing
both maps and sets, keyed by jolt-hash and compared by jolt=. emit.janet
emits :vector/:map/:set literals to the rt constructors and lowers the leaf
ops (conj/get/nth/count/assoc/dissoc/contains?/empty?/peek/pop) via the
native-ops path, with a per-op arity gate.
Also: keyword/map literals in fn position lower to jolt-get ((:k m), ({:k v} k));
arity-1 comparisons emit the vacuous jolt truth (Scheme < rejects a non-number
even at arity 1); count returns a flonum and vector indices coerce from flonum,
both consequences of the all-double number model; values.ss = / hash and the
rt printer learn collections (maps/sets render in HAMT order, so the probe
compares unordered values via =, not printed form).
Subset parity 182 -> 433/436 compiled cases (2219/2655 out of subset), 0 new
divergences. The 3 known divergences are dynamic IFn dispatch (a keyword/vector
held in a local, called as a fn) — deferred to the IFn/protocol increment and
allowlisted in the probe. emit-test 31/31, full run-tests green (125 files).
0c: persistent HAMT on Chez is ~41x faster than Janet's HAMT on the collections
map-churn (258.6 -> 6.3 ms), ~15x off mutable-native (inherent persistence cost).
Decision: self-host the persistent collections in Clojure; substrate is not the
bottleneck. See docs/chez-phase0-results.md.
0a hardening: NUL-separated keyword intern key (no ns/name collision), non-finite
-safe jolt-hash. 37/37.
0a (host/chez/values.ss): Jolt value model on Chez — nil sentinel distinct from
#f/'(), interned keywords, ns+meta symbols, exactness-aware = and consistent
hash. Chez numeric tower gives ratios/bignums free. 33/33 tests.
0b (test/chez/): extract test/spec/*.janet defspec tables into corpus.edn (2655
cases, valid as both EDN and Janet data), and a runner that drives ANY jolt
binary via the CLI boundary with per-case subprocess isolation. Pluggable target
(JOLT_BIN) so the same corpus gates every host. Baseline vs Janet build/jolt:
2641/2655, 14 known CLI divergences allowlisted; gate fails only on NEW ones.
