534007641e
* core: compile macro expanders via staged bootstrap (Stage 2 Task 1)
Macros are now compiled, not interpreted, by steady state — matching
Clojure (macros are ordinary compiled fns the Java seed compiles for
clojure.core) and ClojureScript (macros compiled, invoked at compile
time). Neither reference keeps an interpreted-closure fallback.
The early macros (00-syntax) are defined while the self-hosted analyzer
is still being bootstrapped (it builds lazily after the overlay loads),
so macro-compile-hook returns nil and they get an interpreted closure.
The bootstrap compiler.janet can't substitute (it punts on syntax-quote,
which nearly every expander uses).
Fix = staged bootstrap, the same pattern as the compiler fixpoint:
defmacro stashes the expander source on the var (:macro-src) plus a
:macro-uses-env flag; once the overlay + analyzer are fully built,
backend/recompile-macros! (via ensure-macros-compiled! at the end of
load-core-overlay!) compiles each stashed expander through the now-live
analyzer and rebinds the var, marking :macro-compiled. Idempotent;
&env/&form macros keep the interpreted closure (the compiled fn* has no
such params). The interpreter is now a build-time crutch, gone by
steady state.
Rewrote if-not/if-let/if-some/assert from '& [else]' rest-destructuring
(which the analyzer punts on) to a plain rest param + (first rest), so
all 47 overlay macros compile. Analyzer rest-destructuring gap: jolt-f79.
47/47 overlay macros compiled, 0 interpreted; user macros compile
immediately post-init. Gate green: conformance 267x3, fallback-zero
31/5, bootstrap-fixpoint stage1==2==3, self-host, staged-bootstrap,
lazy-infinite 44/44, clojure-test-suite >=4034/67, sci-bootstrap,
features 78/78, all unit+spec, core-bench neutral.
* core: wrap macro expanders in fn (not fn*) so destructured arglists compile
Follow-up to the staged macro-compile change. The macro-recompile pass
wrapped each expander in the raw fn* primitive, which punts on a
destructuring rest param — so if-not/if-let/if-some/assert (using the
canonical '& [else]') couldn't compile and had been rewritten to plain
rest params as a workaround.
Root cause: fn* is the primitive; the fn MACRO is what desugars
destructuring (rest, map, nested) into the body before lowering. Wrapping
expanders in fn instead of fn* compiles any destructured macro arglist
uniformly, so the workaround is unnecessary — reverted those 4 macros to
the canonical '& [else]' forms.
Net: rest-destructuring is fully compiled for all normal code (fn/defn/
let/macro params). Only the hand-written raw fn* primitive still punts
(jolt-f79, downgraded to P4 — falls back to interpreter, still correct).
47/47 overlay macros compiled. Gate green: conformance 267x3,
fallback-zero 31/5, bootstrap-fixpoint stage1==2==3, self-host,
staged-bootstrap, lazy-infinite 44/44, clojure-test-suite >=4034/67,
sci-bootstrap, features, all unit+spec.
* core: fn*/let*/loop* are plain-symbol primitives, matching Clojure (jolt-f79)
jolt-f79 asked to compile destructuring in fn* rest params. Checking
against Clojure inverts the premise: Clojure's fn* REJECTS destructuring
at compile time ('fn params must be Symbols'; let*/loop* 'Bad binding
form, expected symbol'). So the self-hosted analyzer was already correct
— fn*/let*/loop* are plain-symbol primitives; the fn/let/loop/defn
MACROS desugar destructuring. The real defect was the interpreter
leniently destructuring raw fn*, and defn emitting raw fn* to rely on it.
Changes:
- evaluator: fn*/let*/loop* now reject non-symbol binding forms with
Clojure's exact messages (require-symbol-params/plain-sym?), so the
interpreter agrees with the analyzer + Clojure.
- 00-syntax: defn emits the fn MACRO (not raw fn*) so destructuring
params desugar; unnamed, so self-recursion still resolves via the var.
- 00-syntax: completing that exposed a real gap — the overlay destructure
fn didn't handle kwargs (a map pattern bound against a fn's sequential
rest); it had only worked via the interpreter's destructure-bind. Added
the seq->map coercion to the map? branch (sequential: 1 map elt => that
map, else apply hash-map), matching destructure-bind so interpret ==
compile.
Net: fn*/let*/loop* are plain-symbol primitives across interpreter,
analyzer, and Clojure; all real destructuring (fn/defn/let/loop/macro
params, incl kwargs & {:keys}) compiles through the macros with no
interpreter fallback. Regression spec added.
Gate green: conformance 267x3, fallback-zero 31/5, bootstrap-fixpoint
stage1==2==3, self-host, staged-bootstrap, lazy-infinite 44/44,
clojure-test-suite >=4034/67, sci-bootstrap, features 78/78, all
unit+spec (destructuring 50/50).
* docs: clarify fn*/let*/loop* take plain symbols only (jolt-f79)
grammar.ebnf: the destructuring note already attributed patterns to the
binding MACROS; make the boundary explicit — the fn*/let*/loop* PRIMITIVES
they desugar to take plain symbols only (a non-symbol binding errors, as
in Clojure).
self-hosting-compiler.md: the 'compile destructuring via a shared
destructure expander instead of falling back' item is done (and its
jolt-7dl ref was stale) — destructuring now compiles through the
fn/let/loop/defn macros' desugaring; the primitives reject patterns.
* core: Stage 2 Task 2 tier 1 — compile syntax-quote + definterface/extend/proxy
First slice of moving stateful forms onto the compile path (jolt-eaa).
- loader stateful-head?: drop syntax-quote (the analyzer's `handled` set
already compiles it; routing it to the interpreter was redundant).
- host_iface special-names: drop definterface/extend/proxy (stub macros
expanding to def/nil — their expansions compile once unpunted).
- letfn stays interpreted: its let* expansion needs letrec semantics
(mutual recursion between the fns), which sequential compiled let* lacks
— a later tier.
Gate green: conformance 267x3, fallback-zero 31/5, bootstrap-fixpoint
stage1==2==3, self-host, staged-bootstrap, clojure-test-suite >=4034/67,
features 78/78, all unit + protocol/multimethod/macro specs.
---------
Co-authored-by: Yogthos <yogthos@gmail.com>
361 lines
18 KiB
Clojure
361 lines
18 KiB
Clojure
;; clojure.core — syntax tier. The control macros the compiler and every later
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;; tier depend on (when/cond/and/or/...), expressed as defmacro. Loaded FIRST
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;; (before 00-kernel), interpreted, so the macros exist before any code that uses
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;; them is compiled — including the kernel tier, the self-hosted analyzer, and the
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;; seq/coll tiers.
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;;
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;; CONSTRAINT: a macro here may use ONLY special forms (if/do/let*/fn*/not) and
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;; core-renames SEED primitives (first/next/rest/nth/count/empty?/...). It must
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;; NOT use kernel-tier fns (second/peek/subvec/...) or anything defined later —
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;; those don't exist yet when this tier loads.
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(defmacro when [test & body]
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`(if ~test (do ~@body)))
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(defmacro when-not [test & body]
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`(if (not ~test) (do ~@body)))
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(defmacro and [& exprs]
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(if (empty? exprs)
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true
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(if (empty? (rest exprs))
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(first exprs)
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`(let* [and# ~(first exprs)] (if and# (and ~@(rest exprs)) and#)))))
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(defmacro or [& exprs]
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(if (empty? exprs)
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nil
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(if (empty? (rest exprs))
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(first exprs)
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`(let* [or# ~(first exprs)] (if or# or# (or ~@(rest exprs)))))))
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;; :else (any truthy value) is just a test, so no special case — (if :else e ...)
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;; takes e.
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(defmacro cond [& clauses]
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(if (empty? clauses)
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nil
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`(if ~(first clauses) ~(nth clauses 1) (cond ~@(drop 2 clauses)))))
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;; Threading: a list form threads x in as the first (->) or last (->>) arg; a bare
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;; symbol becomes (form x). Recursive; the expand-once cache makes that free.
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(defmacro -> [x & forms]
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(if (empty? forms)
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x
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(let [form (first forms)
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threaded (if (seq? form)
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`(~(first form) ~x ~@(rest form))
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`(~form ~x))]
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`(-> ~threaded ~@(rest forms)))))
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(defmacro ->> [x & forms]
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(if (empty? forms)
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x
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(let [form (first forms)
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threaded (if (seq? form)
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`(~(first form) ~@(rest form) ~x)
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`(~form ~x))]
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`(->> ~threaded ~@(rest forms)))))
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;; Forward declaration is a no-op on Jolt — the compiler resolves forward refs via
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;; pending cells (matching the prior Janet macro).
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(defmacro declare [& syms] `(do))
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;; destructure — Clojure's binding-vector expander, ported from the Janet seed
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;; (was core-destructure). Turns a binding vector that may contain destructuring
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;; patterns into a plain binding vector (alternating symbol / init-form) built from
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;; nth/nthnext/get, so the COMPILER only ever sees plain symbols (analyze-bindings
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;; rejects patterns). `let` consumes it directly; `loop`/`fn` reuse it transitively
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;; through `let`. Written with let*/fn* and seed primitives only — it never uses
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;; let/loop/fn, so expanding its own body can't recurse back into destructure.
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;; Note map? is true for symbol structs too, so the symbol? clause must come first.
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;; def+fn* (not defn) because the defn macro is not defined until later in the tier.
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(def destructure
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(fn* destructure [bindings]
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(let* [find-or
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(fn* [or-map nm]
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(reduce (fn* [acc k]
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(if (and (symbol? k) (= nm (name k)))
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[true (get or-map k)]
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acc))
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[false nil]
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(if or-map (keys or-map) [])))
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amp? (fn* [x] (and (symbol? x) (= "&" (name x))))
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proc
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(fn* proc [pat init acc]
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(cond
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(symbol? pat) (conj (conj acc pat) init)
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(vector? pat)
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(let* [g (symbol (str (gensym)))
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n (count pat)
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vloop
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(fn* vloop [i idx a]
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(if (< i n)
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(let* [elem (nth pat i)]
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(cond
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(amp? elem)
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(vloop (+ i 2) idx (proc (nth pat (inc i)) `(nthnext ~g ~idx) a))
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(= elem :as)
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(vloop (+ i 2) idx (proc (nth pat (inc i)) g a))
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:else
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(vloop (inc i) (inc idx) (proc elem `(nth ~g ~idx nil) a))))
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a))]
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(vloop 0 0 (conj (conj acc g) init)))
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(map? pat)
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(let* [g (symbol (str (gensym)))
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gm (symbol (str (gensym)))
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;; kwargs: a map pattern may bind against the sequential rest
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;; of a fn — (& {:keys [...]}) — which is a seq of alternating
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;; k/v args, or a single trailing map. Coerce like Clojure (and
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;; like the interpreter's destructure-bind, so interpret/compile
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;; agree): a sequential value with one map element is that map,
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;; otherwise (apply hash-map). A real map value is used as-is, so
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;; ordinary map destructuring is unaffected. g holds init once;
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;; gm is the coerced map every lookup (and :as) reads from.
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coerce `(if (sequential? ~g)
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(if (and (= 1 (count ~g)) (map? (first ~g)))
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(first ~g)
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(apply hash-map ~g))
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~g)
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or-map (get pat :or)
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as-sym (get pat :as)
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bound (conj (conj (conj (conj acc g) init) gm) coerce)
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base (if as-sym (conj (conj bound as-sym) gm) bound)
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group
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(fn* [a kw kind]
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(let* [names (get pat kw)]
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(if names
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(reduce
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;; s is a symbol (a b) or a keyword (:a :b); name/
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;; namespace handle both, so :keys [:major] binds
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;; `major` looking up :major (str would keep the colon).
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(fn* [aa s]
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(let* [local (name s)
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nsp (namespace s)
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keyform (cond
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(= kind :kw) (keyword (if nsp (str nsp "/" local) local))
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(= kind :str) local
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:else `(quote ~(symbol nsp local)))
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fo (find-or or-map local)]
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(conj (conj aa (symbol local))
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(if (nth fo 0)
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`(get ~gm ~keyform ~(nth fo 1))
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`(get ~gm ~keyform)))))
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a names)
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a)))
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g1 (group base :keys :kw)
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g2 (group g1 :strs :str)
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g3 (group g2 :syms :sym)]
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(reduce (fn* [a k]
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(if (keyword? k)
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a
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(proc k `(get ~gm ~(get pat k)) a)))
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g3 (keys pat)))
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:else (throw (str "unsupported destructuring pattern"))))
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ploop
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(fn* ploop [i acc]
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(if (< i (count bindings))
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(ploop (+ i 2) (proc (nth bindings i) (nth bindings (inc i)) acc))
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acc))]
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(ploop 0 []))))
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;; let desugars destructuring patterns to plain bindings (via destructure) so the
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;; COMPILER sees only plain symbols — analyze-bindings rejects patterns as
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;; uncompilable, relying on this macro to have expanded them. (The interpreter
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;; could destructure let* directly, but the compiler can't.) let* is sequential, so
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;; a later init can reference an earlier destructured name. Splice via [~@..] so the
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;; binding vector is a tuple form (destructure returns a pvec), not a pvec literal.
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(defmacro let [bindings & body]
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`(let* [~@(destructure bindings)] ~@body))
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;; loop binds destructuring forms like let, but recur must target the loop* vars,
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;; whose count can't change. So (matching Clojure): gensym one loop var per binding,
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;; loop* over those, and destructure them via an inner let each iteration; an outer
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;; let establishes the destructured names so later inits can see them. Plain loops
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;; (no patterns) pass straight through to loop*.
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(defmacro loop [bindings & body]
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(let [d (destructure bindings)]
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(if (= d bindings)
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`(loop* ~bindings ~@body)
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(let [bs (take-nth 2 bindings)
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vs (take-nth 2 (drop 1 bindings))
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gs (map (fn [b] (if (symbol? b) b (symbol (str (gensym))))) bs)
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outer (reduce (fn [acc t]
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(let [b (nth t 0) v (nth t 1) g (nth t 2)]
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(if (symbol? b) (conj (conj acc g) v)
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(conj (conj (conj (conj acc g) v) b) g))))
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[] (map vector bs vs gs))
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inner (reduce (fn [acc t] (conj (conj acc (nth t 0)) (nth t 1)))
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[] (map vector bs gs))
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loopv (reduce (fn [acc g] (conj (conj acc g) g)) [] gs)]
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;; splice via [~@..] so the binding vectors are tuple forms, not pvecs.
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`(let [~@outer] (loop* [~@loopv] (let [~@inner] ~@body)))))))
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;; fn: desugar destructuring params to plain symbols + a body let (matching
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;; Clojure's maybe-destructured), so fn* only ever sees plain params (the compiler's
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;; analyze-fn requires that). Plain params pass through untouched. Handles an
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;; optional name and single- or multi-arity. md/mk are fn* (not fn) to avoid a cycle.
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;; md walks a param seq, replacing non-symbol patterns with gensyms and recording
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;; [pattern gensym] let-bindings; mk turns one arity (params . body) into a rewritten
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;; arity. Output: single arity splices the arity's elements straight into fn*; multi
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;; arity splices the rewritten clauses.
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(defmacro fn [& raw]
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(let [nm (if (symbol? (first raw)) (first raw) nil)
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aftn (if nm (next raw) raw)
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md (fn* go [ps nps lets]
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(if (seq ps)
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(if (symbol? (first ps))
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(go (next ps) (conj nps (first ps)) lets)
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;; bare (gensym) here is Janet's (a Janet symbol the destructurer
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;; rejects); round-trip through str for a jolt symbol.
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(let [g (symbol (str (gensym)))]
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(go (next ps) (conj nps g) (conj (conj lets (first ps)) g))))
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[nps lets]))
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mk (fn* [sig]
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(let [r (md (seq (first sig)) [] [])]
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(if (empty? (nth r 1))
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sig
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;; build the params/let vectors via [~@..] so they are tuple forms
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;; (the accumulators are plain seqs, the wrong representation).
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(let [pv `[~@(nth r 0)]
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lv `[~@(nth r 1)]]
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`(~pv (let ~lv ~@(rest sig)))))))]
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(if (vector? (first aftn))
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(let [a (mk aftn)]
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(if nm `(fn* ~nm ~@a) `(fn* ~@a)))
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(let [as (vec (map mk aftn))]
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(if nm `(fn* ~nm ~@as) `(fn* ~@as))))))
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;; defn: drop an optional leading docstring and attr-map, then (def name (fn ...)).
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;; Emits the fn MACRO (not the fn* primitive) so destructuring params desugar — fn*
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;; requires plain symbols (like Clojure). Unnamed (as before): self-recursion
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;; resolves through the def'd var, so this only adds the desugaring step.
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;; Both single- and multi-arity reduce to (fn ~@body) — fn takes either a params
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;; vector + body or a sequence of ([params] body) clauses, so no arity branching is
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;; needed. (map? is true for symbol forms too, so guard the attr-map with symbol?.)
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;; Defined before fresh-sym below, which is a defn-.
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(defmacro defn [fn-name & body]
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(let [body (if (and (seq body) (string? (first body))) (rest body) body)
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body (if (and (seq body) (map? (first body)) (not (symbol? (first body))))
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(rest body) body)]
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`(def ~fn-name (fn ~@body))))
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;; Jolt doesn't enforce privacy, so defn- is just defn (matching how Clojure's own
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;; defn- delegates to defn with :private metadata).
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(defmacro defn- [fn-name & body] `(defn ~fn-name ~@body))
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;; A fresh jolt symbol inside a macro body (a bare (gensym) returns a Janet symbol
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;; the destructurer rejects). This defn compiles fine: by the time a tier triggers
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;; the analyzer build the kernel is in place (the build is gated until then).
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(defn- fresh-sym [] (symbol (str (gensym))))
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;; cond->: thread expr through each (test form) pair, only when the test is truthy.
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;; Linear nested let*, a distinct fresh symbol per step.
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(defmacro cond-> [expr & clauses]
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(let [step (fn step [prev cls]
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(if (empty? cls)
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prev
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(let [t (first cls)
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f (nth cls 1)
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gn (fresh-sym)
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call (if (seq? f) `(~(first f) ~prev ~@(rest f)) `(~f ~prev))]
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`(let* [~gn (if ~t ~call ~prev)] ~(step gn (drop 2 cls))))))
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g0 (fresh-sym)]
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`(let* [~g0 ~expr] ~(step g0 clauses))))
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;; case: nested =/or tests (no jump table). Test constants are NOT evaluated —
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;; symbols and list constants are quoted; a list in test position is a set (or).
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(defmacro case [expr & clauses]
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(let [g (fresh-sym)
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mk-const (fn [c] (if (or (symbol? c) (seq? c)) `(quote ~c) c))
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mk-test (fn [c]
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(if (seq? c)
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`(or ~@(map (fn [v] `(= ~g ~(mk-const v))) c))
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`(= ~g ~(mk-const c))))
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build (fn build [cls]
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(if (empty? cls)
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nil
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(if (empty? (rest cls))
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(first cls)
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`(if ~(mk-test (first cls)) ~(nth cls 1) ~(build (drop 2 cls))))))]
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`(let* [~g ~expr] ~(build clauses))))
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;; for: list comprehension, desugared to nested map/mapcat over the binding colls.
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;; Per binding group: :when wraps the inner form in (if test (list inner) []) so
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;; mapcat drops it when false; :let wraps it in a let*; :while wraps the coll in
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;; take-while. The last group with no modifiers is a plain map (no flatten needed).
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;; Faithful port of the prior Janet macro (single body expr). The body uses only
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;; kernel/seed fns so it runs at analyzer-build time. `fn` (not fn*) carries the
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;; binding so destructuring forms work.
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(defmacro for [bindings body]
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(let [scan (fn scan [bvec i bind coll mods]
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(if (and (< i (count bvec)) (keyword? (nth bvec i)))
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(let [k (nth bvec i)
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v (nth bvec (inc i))]
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(cond
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(= k :when) (scan bvec (+ i 2) bind coll (conj mods [:when v]))
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(= k :let) (scan bvec (+ i 2) bind coll (conj mods [:let v]))
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(= k :while) (scan bvec (+ i 2) bind `(take-while (fn [~bind] ~v) ~coll) mods)
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:else (scan bvec (inc i) bind coll mods)))
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[i bind coll mods]))
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parse-groups (fn parse-groups [bvec i groups]
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(if (>= i (count bvec))
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groups
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(let [r (scan bvec (+ i 2) (nth bvec i) (nth bvec (inc i)) [])]
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(parse-groups bvec (nth r 0)
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(conj groups [(nth r 1) (nth r 2) (nth r 3)])))))
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;; Apply the group's modifiers around a contribution that is ALREADY a seq
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;; (a (list body) for the last group, an inner comprehension otherwise), so
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;; :when just returns it or [] — no extra (list ...) that mapcat couldn't
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;; flatten. :let binds around it; mods apply outer-to-inner (left to right).
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wrap-mods (fn wrap-mods [mods inner]
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(if (empty? mods)
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inner
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(let [m (first mods)
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sub (wrap-mods (rest mods) inner)]
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(if (= (first m) :when)
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`(if ~(nth m 1) ~sub [])
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`(let* ~(nth m 1) ~sub)))))
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|
build (fn build [idx groups]
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|
(let [g (nth groups idx)
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|
my-bind (nth g 0)
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|
my-coll (nth g 1)
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|
my-mods (nth g 2)
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|
is-last (= idx (dec (count groups)))]
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|
(if (and is-last (empty? my-mods))
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|
;; fast path: last group, no modifiers -> a plain map of body
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|
`(map (fn [~my-bind] ~body) ~my-coll)
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|
;; general: mapcat over a seq contribution (wrap a last-group
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|
;; body in a one-element list so mapcat yields the bodies).
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|
(let [base (if is-last `(list ~body) (build (inc idx) groups))]
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|
`(mapcat (fn [~my-bind] ~(wrap-mods my-mods base)) ~my-coll)))))]
|
|
(if (>= (count bindings) 2)
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|
(build 0 (parse-groups bindings 0 []))
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|
body)))
|
|
|
|
;; doseq runs body for side effects across the bindings, returning nil. Same
|
|
;; shortcut as the prior Janet macro: realize a `for` comprehension with count
|
|
;; (for handles :when/:let/:while and multiple bindings).
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|
(defmacro doseq [bindings & body]
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|
`(do (count (for ~bindings (do ~@body nil))) nil))
|
|
|
|
;; when-let must live in this (early) tier, not 30-macros with its if-let/if-some/
|
|
;; when-some siblings: 20-coll uses it (not-empty), and 20-coll loads before 30. The
|
|
;; name binds only in the taken branch (temp# tests the value); via `let` so the
|
|
;; binding form may itself destructure, matching Clojure.
|
|
(defmacro when-let [bindings & body]
|
|
(let [form (bindings 0) tst (bindings 1)]
|
|
`(let [temp# ~tst]
|
|
(if temp# (let [~form temp#] ~@body) nil))))
|
|
|
|
;; lazy-seq / lazy-cat live here (not 30-macros) because the seq/coll tiers use
|
|
;; them and compile-as-they-load: the macro must be registered before those tiers
|
|
;; or (lazy-seq …) compiles to a call of the macro-as-function and leaks its
|
|
;; expansion at runtime (jolt-r81). They use only seed fns (make-lazy-seq/
|
|
;; coll->cells/concat) + map, all available from the start.
|
|
;; lazy-seq defers its body: make-lazy-seq holds a thunk that realizes the body
|
|
;; to cells when forced. lazy-cat wraps each coll in a lazy-seq and concats.
|
|
(defmacro lazy-seq [& body]
|
|
`(make-lazy-seq (fn* [] (coll->cells (do ~@body)))))
|
|
|
|
(defmacro lazy-cat [& colls]
|
|
`(concat ~@(map (fn [c] `(lazy-seq ~c)) colls)))
|