Rephrase comments that pointed at deleted Janet files (emit.janet, the seed
sources, 'the Janet back end punts ...') to present-tense descriptions of the
Chez behavior. Comment/docstring-only; the self-host fixpoint is unchanged
(comments don't affect the compiled seed).
Delete five files that were Janet-host shims with no Chez path: clojure.java.io
(provided natively by host/chez/io.ss), and jolt.{nrepl,png,interop,shell}
(the janet.* bridge, os/shell, janet.net — none exist on Chez).
jolt-cf1q.6
510 lines
25 KiB
Clojure
510 lines
25 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: code here may use ONLY special forms (if/do/let*/fn*/not) and
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;; SEED primitives (first/next/rest/nth/count/seq/...), plus earlier defs in
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;; THIS file. It must NOT use kernel-tier fns (second/peek/subvec/...) or
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;; anything defined later — those don't exist yet when this tier loads. Raw
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;; fn*/let* (no destructuring) and no when/cond/and/or above their defmacros.
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;;
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;; This tier's defns load interpreted and are recompiled by the staged pass
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;; (backend/recompile-defns!) once the analyzer is alive — same lifecycle as
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;; the defmacro expanders.
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;; zero?/pos?/every? live HERE (not 20-coll): empty? below calls zero?, and
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;; the self-hosted analyzer — compiled right after the kernel tier — uses all
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;; three. Raw def+fn* per the file constraint. zero? checks number? itself
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;; (= doesn't throw); pos? inherits throwing from >.
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(def zero?
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(fn* zero? [x]
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(if (number? x)
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(= x 0)
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(throw (str "zero? requires a number, got: " x)))))
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;; pos? checks number? explicitly: this tier is recompiled by the staged pass,
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;; where a bare (> x 0) emits the native janet op that happily orders strings
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;; (the documented native-ops relaxation) — the guard keeps Clojure's throw.
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(def pos?
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(fn* pos? [x]
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(if (number? x)
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(> x 0)
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(throw (str "pos? requires a number, got: " x)))))
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;; Canonical every?: short-circuits on the first falsey result, so infinite
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;; seqs with an early counterexample terminate.
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(def every?
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(fn* every? [pred coll]
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(if (nil? (seq coll))
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true
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(if (pred (first coll))
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(recur pred (next coll))
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false))))
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;; empty?/keys/vals live HERE (not 20-coll) because the expanders below call
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;; them at expansion time, which first happens during the kernel-tier compile.
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;; empty? keeps O(1) dispatch for counted things; only the lazy/list fallback
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;; goes through seq's cell check.
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(def empty?
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(fn* empty? [coll]
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(if (nil? coll)
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true
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(if (vector? coll)
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(zero? (count coll))
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(if (map? coll)
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(zero? (count coll))
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(if (set? coll)
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(zero? (count coll))
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(if (string? coll)
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(zero? (count coll))
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(nil? (seq coll)))))))))
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;; Canonical: the seq of entries/elements, projected. (keys {}) is nil; sorted
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;; maps iterate in comparator order ((seq sm) is the value's own :seq op).
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(def keys
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(fn* keys [m]
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(let* [s (seq m)]
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(if s (map (fn* [e] (nth e 0)) s) nil))))
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(def vals
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(fn* vals [m]
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(let* [s (seq m)]
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(if s (map (fn* [e] (nth e 1)) s) nil))))
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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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;; ns is sugar over the namespace-op fns (in-ns/require/use/import/refer-clojure,
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;; all ctx-capturing clojure.core fns) — matching Clojure, where require is a fn and
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;; the ns macro expands its clauses into require calls. Each spec is quoted
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;; individually and passed as data; non-list clauses (docstring, attr-map,
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;; :gen-class, …) are ignored. So ns compiles to a plain (do …) of invokes.
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;; MUST live in this first tier: the self-hosted analyzer build (triggered while
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;; 10-seq loads) processes jolt.analyzer's own (ns …) form, so ns has to exist by
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;; then. Its body resolves fn/map/reduce/cond at EXPANSION time, by which point all
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;; of 00-syntax has loaded, so using them here is fine.
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(defmacro ns [nm & clauses]
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;; ^{:map} metadata on the ns name reads as a (with-meta sym {...}) form, not an
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;; annotated symbol (jolt-8w2). Real libraries put :author/:doc there
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;; (clojure.tools.logging), so unwrap to the bare symbol; jolt does not track
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;; namespace metadata, so the map is dropped.
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(let [nm (if (and (seq? nm) (= 'with-meta (first nm))) (second nm) nm)
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calls (reduce
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(fn [acc clause]
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(if (seq? clause)
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(let [head (first clause) args (rest clause)]
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(cond
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(= head :require) (conj acc `(require ~@(map (fn [s] `(quote ~s)) args)))
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(= head :use) (conj acc `(use ~@(map (fn [s] `(quote ~s)) args)))
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(= head :import) (conj acc `(import ~@(map (fn [s] `(quote ~s)) args)))
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(= head :refer-clojure)
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(conj acc `(refer-clojure ~@(map (fn [s] `(quote ~s)) args)))
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:else acc))
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acc))
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[] clauses)]
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`(do (in-ns (quote ~nm)) ~@calls)))
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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 interns unbound vars (Clojure semantics). The interpreter
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;; resolves forward refs lazily either way, but the COMPILER classifies globals at
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;; compile time: without the var, a declared name that collides with a Janet root
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;; binding (parse, hash, …) would compile to the host fn instead of the var.
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(defmacro declare [& syms]
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`(do ~@(map (fn* [s] `(def ~s)) syms)))
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;; destructure — Clojure's binding-vector expander.
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;; 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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;; a return-type hint (defn f ^bytes [x] ...) reaches us as a
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;; (with-meta [x] {:tag ...}) FORM in params position — unwrap it
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;; (the hint means nothing on jolt; ring-codec carries several).
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unhint (fn* [x]
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(if (if (seq? x) (= 'with-meta (first x)) false)
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(nth x 1)
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x))
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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 [ps (unhint (first sig))
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hinted (not (= ps (first sig)))
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r (md (seq ps) [] [])]
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(if (if (empty? (nth r 1)) (not hinted) false)
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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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;; A hinted-but-undestructured arity also rebuilds, to shed the
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;; with-meta wrapper without changing the clause representation.
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(let [pv `[~@(nth r 0)]
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lv `[~@(nth r 1)]]
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(if (empty? (nth r 1))
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`(~pv ~@(rest sig))
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`(~pv (let ~lv ~@(rest sig))))))))]
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(if (vector? (unhint (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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;; ^{:map} metadata on the name reads as a (with-meta sym …) form, not an
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;; annotated symbol (jolt-8w2). def attaches the metadata, but fn needs a
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;; bare symbol, so unwrap it for the fn name.
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fn-only-name (if (symbol? fn-name) fn-name (first (rest fn-name)))]
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;; pass the name through to fn: the compiled fn's janet name carries it,
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;; so stack traces read app.deep/level3 instead of a gensym (jolt-2o7.1)
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`(def ~fn-name (fn ~fn-only-name ~@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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;; Collect test constants pairwise (so a trailing unpaired default is
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;; excluded), flattening list/or-group tests into individual constants.
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;; seed-only fns (reduce/conj/first/rest/drop/empty?/seq?) — analyzer.clj
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;; uses case during its own build, before some/distinct load.
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collect (fn* collect [cls acc]
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(if (or (empty? cls) (empty? (rest cls)))
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acc
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(let [t (first cls)
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acc (if (seq? t) (reduce conj acc t) (conj acc t))]
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(collect (drop 2 cls) acc))))
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;; first duplicate constant, wrapped in [x] (so a duplicate nil is detected);
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;; nil = none. Clojure rejects duplicate case constants at compile time.
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first-dup (fn* fd [items seen]
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(if (empty? items)
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nil
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(let [x (first items)]
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(if (reduce (fn [f s] (or f (= s x))) false seen)
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[x]
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(fd (rest items) (conj seen x))))))
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dup (first-dup (collect clauses []) [])
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build (fn build [cls]
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(if (empty? cls)
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;; no clause matched and no default — Clojure throws here.
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`(throw (ex-info (str "No matching clause: " ~g) {}))
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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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(if dup
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(throw (str "Duplicate case test constant: " (first dup)))
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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
|
|
(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)
|
|
;; general: mapcat over a seq contribution (wrap a last-group
|
|
;; body in a one-element list so mapcat yields the bodies).
|
|
(let [base (if is-last `(list ~body) (build (inc idx) groups))]
|
|
`(mapcat (fn [~my-bind] ~(wrap-mods my-mods base)) ~my-coll)))))]
|
|
(if (>= (count bindings) 2)
|
|
(build 0 (parse-groups bindings 0 []))
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|
body)))
|
|
|
|
;; doseq runs body for side effects across the bindings, returning nil. Same
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|
;; shortcut as the prior Janet macro: realize a `for` comprehension with count
|
|
;; (for handles :when/:let/:while and multiple bindings).
|
|
(defmacro doseq [bindings & body]
|
|
`(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)))
|
|
|
|
;; not= here (not 20-coll): the kernel tier uses it, and the kernel
|
|
;; bootstrap-compiles right after this file loads. Canonical Clojure arities.
|
|
(defn not=
|
|
([x] false)
|
|
([x y] (not (= x y)))
|
|
([x y & more] (not (apply = x y more))))
|
|
|
|
;; unreduced here: the seq tier's reduce machinery unwraps with it.
|
|
(defn unreduced [x] (if (reduced? x) (deref x) x))
|