jolt/jolt-core/clojure/core/30-macros.clj
Yogthos e611034550 core: move if-let/if-some/when-some/while/dotimes macros to overlay
Phase 3 batch 2 (jolt-1j0), 5 user-facing macros as defmacro + syntax-quote.
The conditional-binding macros use the auto-gensym temp# idiom so the name binds
only in the taken branch (the else/empty branch sees the outer scope, carrying
forward the earlier scope fix). when-let stays in Janet for now — 20-coll uses
it, so it must remain available before the macro tier loads.

Note: gensym in a macro body resolves to Janet's 0-arity builtin, so explicit
(gensym "prefix") fails — use template auto-gensym (foo#) instead.

conformance 228/228 x3, full suite green (incl. the if-let scope regression spec,
now exercising the overlay macro), clojure-test-suite 3930, bench A/B flat.
2026-06-07 00:38:02 -04:00

45 lines
1.9 KiB
Clojure

;; clojure.core — macro tier. Macros expressed in Clojure (defmacro + syntax-quote)
;; rather than as hand-built Janet form-transformers. Loaded after the fn tiers,
;; so a macro here may use any already-frozen core fn/macro.
;;
;; IMPORTANT — only macros NOT used by the self-hosted compiler (jolt-core/jolt/*)
;; or by the earlier overlay tiers belong here; those (and/or/when/when-not/
;; when-let/cond/case/doseq/declare/cond->/->) must stay available before this
;; tier loads, so they remain in Janet for now. Everything here is user-facing.
;;
;; Migration: remove the Janet core-X macro fn AND its core-macro-names entry when
;; moving a macro here (defmacro installs the :macro flag itself).
(defmacro comment [& body] nil)
;; Single arglist (Jolt defmacro is single-arity); the optional else defaults nil
;; via rest-destructuring.
(defmacro if-not [test then & [else]]
`(if (not ~test) ~then ~else))
;; Conditional binding macros: the name is bound ONLY in the taken branch (the
;; auto-gensym temp# tests the value; the else/empty branch sees the surrounding
;; scope). temp# is a single template-local gensym — referenced twice, same symbol.
(defmacro if-let [bindings then & [else]]
(let [form (bindings 0) tst (bindings 1)]
`(let [temp# ~tst]
(if temp# (let [~form temp#] ~then) ~else))))
(defmacro if-some [bindings then & [else]]
(let [form (bindings 0) tst (bindings 1)]
`(let [temp# ~tst]
(if (some? temp#) (let [~form temp#] ~then) ~else))))
(defmacro when-some [bindings & body]
(let [form (bindings 0) tst (bindings 1)]
`(let [temp# ~tst]
(if (some? temp#) (let [~form temp#] ~@body) nil))))
(defmacro while [test & body]
`(loop [] (when ~test ~@body (recur))))
(defmacro dotimes [bindings & body]
(let [i (bindings 0) n (bindings 1)]
`(let [n# ~n]
(loop [~i 0]
(when (< ~i n#) ~@body (recur (inc ~i)))))))