programming-languages学习
目录
- 1. 最简单的算术表达式解析
- 2. 实现MUPL语言
1 最简单的算术表达式解析
实现加减表达式,最原始版本:
(ns my.eval1) (defn Const [i] (list :Const i)) (defn Negate [e] (list :Negate e)) (defn Add [e1 e2] (list :Add e1 e2)) (defn Multiply [e1 e2] (list :Multiply e1 e2)) (defn Const? [x] (= (first x) :Const)) (defn Negate? [x] (= (first x) :Negate)) (defn Add? [x] (= (first x) :Add)) (defn Multiply? [x] (= (first x) :Multiply)) (defn Const-int [e] (first (rest e))) (defn Negate-e [e] (first (rest e))) (defn Add-e1 [e] (first (rest e))) (defn Add-e2 [e] (first (rest (rest e)))) (defn Multiply-e1 [e] (first (rest e))) (defn Multiply-e2 [e] (first (rest (rest e)))) (defn eval-exp [e] (cond (Const? e) e (Negate? e) (Const (- (Const-int (eval-exp (Negate-e e))))) (Add? e) (let [v1 (Const-int (eval-exp (Add-e1 e))) v2 (Const-int (eval-exp (Add-e2 e)))] (Const (+ v1 v2))) (Multiply? e) (let [v1 (Const-int (eval-exp (Multiply-e1 e))) v2 (Const-int (eval-exp (Multiply-e2 e)))] (Const (* v1 v2))) :else (throw (Exception. "eval-exp expected an exp")))) (eval-exp (Add (Const 9) (Const 1)))
(:Const 10)
使用map方式实现：
(ns my.eval2) (defn const [val] {:type ::const :val val}) (defn negate [e] {:type ::negate :e e}) (defn add [e1 e2] {:type ::add :e1 e1 :e2 e2}) (defn multiply [e1 e2] {:type ::multiply :e1 e1 :e2 e2}) (defn eval-exp [e] (case (:type e) ::const e ::negate (const (- (:val (eval-exp (:e e))))) ::add (const (let [v1 (:val (eval-exp (:e1 e))) v2 (:val (eval-exp (:e2 e)))] (+ v1 v2))) ::multiply (const (let [v1 (:val (eval-exp (:e1 e))) v2 (:val (eval-exp (:e2 e)))] (* v1 v2))) (throw (Exception. "eval-exp expected an exp")))) (eval-exp (multiply (const 8) (negate (const 2))))
{:type :my.eval2/const, :val -16}
使用multi method实现,更大的灵活性:
(ns my.eval3) (defn const [val] {:type ::const :val val}) (defn negate [e] {:type ::negate :e e}) (defn add [e1 e2] {:type ::add :e1 e1 :e2 e2}) (defn multiply [e1 e2] {:type ::multiply :e1 e1 :e2 e2}) (defmulti my-eval :type) (defmethod my-eval ::const [e] e) (defmethod my-eval ::negate [{:keys [e]}] (const (- (:val (my-eval e))))) (defmethod my-eval ::add [{:keys [e1 e2]}] (const (+ (:val (my-eval e1)) (:val (my-eval e2))))) (defmethod my-eval ::multiply [{:keys [e1 e2]}] (const (* (:val (my-eval e1)) (:val (my-eval e2))))) (defmethod my-eval :default [_] (throw (Exception. "eval-exp expected an exp"))) (my-eval (multiply (const 8) (negate (const 3))))
{:type :my.eval3/const, :val -24}
使用record实现：
(ns my.eval4) (defprotocol Evalable (my-eval2 [e])) (defrecord Const [val] Evalable (my-eval2 [e] e)) (defrecord Negate [e] Evalable (my-eval2 [e] (Const. (- (:val (my-eval2 (:e e))))))) (defrecord Add [e1 e2] Evalable (my-eval2 [e] (Const. (+ (:val (my-eval2 (:e1 e))) (:val (my-eval2 (:e2 e))))))) (defrecord Multiply [e1 e2] Evalable (my-eval2 [e] (Const. (* (:val (my-eval2 (:e1 e))) (:val (my-eval2 (:e2 e))))))) (extend-type Object Evalable (my-eval2 [_] (throw (Exception. "eval-exp expected an exp")))) (prn (my-eval2 (Add. (Const. 9) (Negate. (Const. 3)))))
#my.eval4.Const{:val 6}
nil
2 实现MUPL语言
支持变量，函数
1: (ns my.lang 2: (:refer-clojure :exclude [int int?])) 3: ;; 这里用到int,和clojure库中的同名，有冲突，要排除掉 4: ;; 另外var是clojure的special form，无法覆盖，只能换个名字。 5: 6: (defn variable [key] {:type ::var :key key}) 7: (defn variable? [e] (= ::var (:type e))) 8: (defn variable-name [e] (:key e)) 9: 10: (defn int [num] {:type ::int :num num}) 11: (defn int? [e] (= ::int (:type e))) 12: (defn int-v [e] (:num e)) 13: 14: (defn add [e1 e2] {:type ::add :e1 e1 :e2 e2}) 15: (defn add? [e] (= ::add (:type e))) 16: (defn add-e1 [e] (:e1 e)) 17: (defn add-e2 [e] (:e2 e)) 18: 19: (defn ifgreater [e1 e2 e3 e4] {:type ::ifgreater :e1 e1 :e2 e2 20: :e3 e3 :e4 e4}) 21: (defn ifgreater? [e] (= ::ifgreater (:type e))) 22: (defn ifgreater-e1 [e] = (:e1 e)) 23: (defn ifgreater-e2 [e] = (:e2 e)) 24: (defn ifgreater-e3 [e] = (:e3 e)) 25: (defn ifgreater-e4 [e] = (:e4 e)) 26: 27: ;; nameopt为可选的函数名，用于实现递归, formal为单个函数参数 28: (defn fun [nameopt formal body] {:type ::fun :nameopt nameopt 29: :formal formal :body body}) 30: (defn fun? [e] (= ::fun(:type e))) 31: (defn fun-name [e] (:nameopt e)) 32: (defn fun-arg [e] (:formal e)) 33: (defn fun-body [e] (:body e)) 34: 35: ;; function call, funexp为闭包， actual为实参 36: (defn call [funexp actual] {:type ::call :funexp funexp 37: :actual actual}) 38: (defn call? [e] (= ::call (:type e))) 39: (defn call-fun [e] (:funexp e)) 40: (defn call-arg [e] (:actual e)) ;实参 41: 42: ;; local binding 43: (defn mlet [variable e body] {:type ::mlet :variable variable 44: :e e :body body}) 45: (defn mlet? [e] (= ::mlet (:type e))) 46: (defn mlet-var [e] (:variable e)) 47: (defn mlet-e [e] (:e e)) 48: (defn mlet-body [e] (:body e)) 49: 50: ;; pair 51: (defn apair [e1 e2] {:type ::apair :e1 e1 :e2 e2}) 52: (defn apair? [e] (= ::apair (:type e))) 53: (defn apair-l [e] (:e1 e)) 54: (defn apair-r [e] (:e2 e)) 55: 56: (defn fst [e] {:type ::fst :e e}) 57: (defn fst? [e] (= ::fst (:type e))) 58: (defn fst-e [e] (:e e)) 59: 60: (defn snd [e] {:type ::snd :e e}) 61: (defn snd? [e] (= ::snd (:type e))) 62: (defn snd-e [e] (:e e)) 63: 64: ;; null 65: (defn aunit [] {:type ::aunit}) 66: (defn aunit? [e] (= ::aunit (:type e))) 67: 68: (defn isaunit [e] {:type ::isaunit :e e}) 69: (defn isaunit? [e] (= ::isaunit (:type e))) 70: (defn isaunit-e [e] (:e e)) 71: 72: ;; closure,用于表示函数的内部实现。 73: (defn closure [env fun] {:type ::closure :env env :fun fun}) 74: (defn closure? [e] (= ::closure (:type e))) 75: (defn closure-env [e] (:env e)) 76: (defn closure-fun [e] (:fun e)) 77: 78: (defn vec->mupllist 79: [xs] 80: (reduce #(apair %2 %1) (aunit) (rseq xs))) 81: (vec->mupllist [(int 1) (int 2) (int 3)]) 82: ;; => {:type :my.lang/apair, 83: ;; :e1 {:type :my.lang/int, :num 1}, 84: ;; :e2 85: ;; {:type :my.lang/apair, 86: ;; :e1 {:type :my.lang/int, :num 2}, 87: ;; :e2 88: ;; {:type :my.lang/apair, 89: ;; :e1 {:type :my.lang/int, :num 3}, 90: ;; :e2 {:type :my.lang/aunit}}}} 91: 92: (defn mupllist->vec 93: [e] 94: (cond 95: (apair? e)(conj (mupllist->vec (apair-r e)) (apair-l e)) 96: (aunit? e) '() ;用loop 累加可以用vector,效率高,递归用list头部添加效率高 97: :else (throw (Exception. "mupllist->vec not a valid mupl list")))) 98: 99: (defn lookup-env-val 100: "从环境中获得变量值,返回nil表示不存在此变量" 101: [env key] 102: (env key)) 103: 104: (defn define-var 105: "定义一个变量,返回新的环境" 106: [var value env] 107: (assoc env var value)) 108: 109: ;; set同define语义不同，但由于环境是不可变的，实现相同 110: (def set-var "设置一个变量，并返回新的环境" define-var) 111: 112: (defn eval-under-env 113: [e env] 114: (cond 115: (int? e) e 116: (aunit? e) e 117: (closure? e) e 118: (variable? e) (lookup-env-val env (variable-name e)) 119: (add? e) (let [v1 (eval-under-env (add-e1 e) env) 120: v2 (eval-under-env (add-e2 e) env)] 121: (if (and (int? v1) (int? v2)) 122: (int (+ (int-v v1) (int-v v2))) 123: (throw (Exception. "MUPL addition applied to non-number")))) 124: (fun? e) (closure env e) 125: (ifgreater? e) (let [v1-test (eval-under-env (ifgreater-e1 e) env) 126: v2-test (eval-under-env (ifgreater-e2 e) env)] 127: (if (and (int? v1-test) (int? v2-test)) 128: (if (> (int-v v1-test) (int-v v2-test)) 129: (eval-under-env (ifgreater-e3 e) env) 130: (eval-under-env (ifgreater-e4 e) env)) 131: (throw (Exception. "MUPL ifgreater condition applied to non-number")))) 132: (mlet? e) (let [n (mlet-var e) 133: v (mlet-e e) 134: nenv (define-var n (eval-under-env v env) env)] 135: (eval-under-env (mlet-body e) nenv)) 136: (call? e) (let [c (eval-under-env (call-fun e) env) 137: arg (eval-under-env (call-arg e) env)] 138: (if (closure? c) 139: (let [fenv (closure-env c) 140: f (closure-fun c) 141: fname (fun-name f) 142: farg (fun-arg f) 143: fbody (fun-body f) 144: 145: ;; 添加环境，函数名和实参绑定 146: fenv (define-var farg arg fenv) 147: fenv (if fname (define-var fname c fenv) 148: fenv)] 149: (eval-under-env fbody fenv)) 150: (throw (Exception. "MUPL call apllied to non-closure")))) 151: (apair? e) (let [l (eval-under-env (apair-l e) env) 152: r (eval-under-env (apair-r e) env)] 153: (apair l r)) 154: (fst? e) (let [v (eval-under-env (fst-e e) env)] 155: (if (apair? v) 156: (apair-l v) 157: (throw (Exception. "MUPL fst apllied to non-pair")))) 158: (snd? e) (let [v (eval-under-env (snd-e e) env)] 159: (if (apair? v) 160: (apair-r v) 161: (throw (Exception. "MUPL snd apllied to non-pair")))) 162: (isaunit? e) (let [v (eval-under-env (isaunit-e e) env)] 163: (if (aunit? v) 164: (int 1) 165: (int 0))) 166: :else (throw (Exception. (str "eval-exp expected an exp, but given:" e))))) 167: 168: (defn eval-exp 169: [e] 170: (eval-under-env e {})) 171: 172: (eval-exp (add (int 3) (int 4))) 173: ;; => {:type :my.lang/int, :num 7} 174: 175: (eval-exp (ifgreater (int 3) (int 4) (int 3) (int 4))) 176: ;; => {:type :my.lang/int, :num 4} 177: 178: (eval-exp (ifgreater (int 5) (int 4) (int 5) (int 4))) 179: ;; => {:type :my.lang/int, :num 5} 180: 181: (eval-exp (mlet :x (int 1) (add (int 5) (variable :x)))) 182: ;; => {:type :my.lang/int, :num 6} 183: 184: (eval-exp (call (fun false "x" (add (variable "x") (int 8))) 185: (int 2))) 186: ;; => {:type :my.lang/int, :num 10} 187: 188: (eval-exp (snd (apair (int 1) (int 2)))) 189: ;; => {:type :my.lang/int, :num 2} 190: 191: (eval-exp (fst (apair (int 1) (int 2)))) 192: ;; => {:type :my.lang/int, :num 1} 193: 194: (eval-exp (isaunit (fun false "x" (aunit)))) 195: ;; => {:type :my.lang/int, :num 0} 196: 197: (eval-exp (isaunit (call (fun false "x" (aunit)) (int 0)))) 198: ;; => {:type :my.lang/int, :num 1} 199: 200: ;; 测试递归函数 201: (def add-x (fun "add" "x" 202: (ifgreater (int 1) 203: (variable "x") 204: (int 0) 205: (add (variable "x") (call (variable "add") 206: (add (variable "x") 207: (int -1))))))) 208: (eval-exp (call add-x (int 10))) 209: ;; => {:type :my.lang/int, :num 55} 210: 211: ;; 同名变量遮盖测试 212: (eval-exp (mlet "x" (int 100) (add (call add-x (int 10)) 213: (variable "x")))) 214: ;; => {:type :my.lang/int, :num 155} 215: 216: ;; 以下函数等同于宏 217: (defn ifaunit 218: [e1 e2 e3] 219: (ifgreater (isaunit e1) (int 0) e2 e3)) 220: 221: (eval-exp (ifaunit (int 0) (int 3) (int 4))) 222: ;; => {:type :my.lang/int, :num 4} 223: 224: (defn mlet* 225: [xs fe] 226: (let [l (apair-l xs) 227: vname (apair-l l) 228: e (apair-r l) 229: r (apair-r xs)] 230: (mlet vname e 231: (if (aunit? r) 232: fe 233: (mlet* r fe))))) 234: 235: (def m1 (mlet* (vec->mupllist [(apair "x" (int 1)) 236: (apair "y" (add (variable "x") (int 2))) 237: (apair "z" (add (variable "y") (int 3)))]) 238: (add (variable "x") 239: (variable "z")))) 240: 241: (eval-exp m1) 242: ;; => {:type :my.lang/int, :num 7} 243: 244: ;; 存在变量名字遮蔽的问题，没有实现卫生宏，会被动态作用域影响 245: (defn ifeq 246: [e1 e2 e3 e4] 247: (mlet "_x" e1 248: (mlet "_y" e2 249: (ifgreater (variable "_x") 250: (variable "_y") 251: e4 252: (ifgreater (variable "_y") 253: (variable "_x") 254: e4 255: e3))))) 256: (eval-exp (ifeq (int 1) (int 2) (int 3) (int 4))) 257: ;; => {:type :my.lang/int, :num 4} 258: 259: (eval-exp (ifeq (int 3) (int 3) (int 1) (int 2))) 260: ;; => {:type :my.lang/int, :num 1} 261: 262: (def sum-xs (fun "sum" "xs" 263: (ifaunit (variable "xs") 264: (int 0) 265: (add (fst (variable "xs")) 266: (call (variable "sum") (snd (variable "xs"))))))) 267: 268: (eval-exp (call sum-xs (vec->mupllist [(int 1) (int 2) (int 3) (int 4) (int 5)]))) 269: ;; => {:type :my.lang/int, :num 15} 270: 271: (def mupl-map (fun "map" "f" 272: (fun false "xs" 273: (ifaunit (variable "xs") 274: (aunit) 275: (apair (call (variable "f") (fst (variable "xs"))) 276: (call (call (variable "map") (variable "f")) 277: (snd (variable "xs")))))))) 278: (-> (eval-exp (call (call mupl-map (fun false "x" (add (variable "x") (int 1)))) 279: (vec->mupllist [(int 1) (int 2) (int 3)]))) 280: mupllist->vec) 281: ;; => ({:type :my.lang/int, :num 2} 282: ;; {:type :my.lang/int, :num 3} 283: ;; {:type :my.lang/int, :num 4}) 284: 285: (def mupl-mapAddN (mlet "map" mupl-map 286: (fun false "i" 287: (call (variable "map") 288: (fun false "x" 289: (add (variable "i") 290: (variable "x"))))))) 291: 292: (-> (eval-exp (call (call mupl-mapAddN (int 4)) 293: (vec->mupllist [(int 1) (int 2) (int 3)]))) 294: mupllist->vec) 295: ;; => ({:type :my.lang/int, :num 5} 296: ;; {:type :my.lang/int, :num 6} 297: ;; {:type :my.lang/int, :num 7})
用record实现，包装函数用于减少改动，用record实现的话，堆栈中异常定位比较麻烦， 无法直接定位到出错的地方:
1: (ns my.lang2 2: (:refer-clojure :exclude [int int?])) 3: ;; 用record重新实现MUPL语言 4: 5: (defn lookup-env-val 6: "从环境中获得变量值,返回nil表示不存在此变量" 7: [env key] 8: (env key)) 9: 10: (defn define-var 11: "定义一个变量,返回新的环境" 12: [var value env] 13: (assoc env var value)) 14: 15: (defprotocol Evalable 16: (eval-under-env [e env])) 17: 18: (defrecord Variable [name] 19: Evalable 20: (eval-under-env [e env] (lookup-env-val env (:name e)))) 21: (defn variable [v] (Variable. v)) 22: 23: (defrecord Int [num] 24: Evalable 25: (eval-under-env [e env] e)) 26: 27: (defn int [n] (Int. n)) 28: (defn int-v [e] (:num e)) 29: (defn int? [e] (instance? Int e)) 30: 31: (defrecord Closure [env fun] 32: Evalable 33: (eval-under-env [e env] e)) 34: (defn closure [e f] (Closure. e f)) 35: (defn closure? [e] (instance? Closure e)) 36: (defn closure-env [e] (:env e)) 37: (defn closure-fun [e] (:fun e)) 38: 39: (defrecord Aunit [] 40: Evalable 41: (eval-under-env [e env] e)) 42: (defn aunit [] (Aunit.)) 43: (defn aunit? [e] (instance? Aunit e)) 44: 45: (defrecord Add [e1 e2] 46: Evalable 47: (eval-under-env [e env] 48: (let [v1 (eval-under-env (:e1 e) env) 49: v2 (eval-under-env (:e2 e) env)] 50: (if (and (int? v1) (int? v2)) 51: (int (+ (int-v v1) (int-v v2))) 52: (throw (Exception. "MUPL addition applied to non-number")))))) 53: (defn add [e1 e2] (Add. e1 e2)) 54: 55: (defrecord Fun [nameopt formal body] 56: Evalable 57: (eval-under-env [e env] (closure env e))) 58: (defn fun [nameopt formal body] (Fun. nameopt formal body)) 59: (defn fun-name [e] (:nameopt e)) 60: (defn fun-arg [e] (:formal e)) 61: (defn fun-body [e] (:body e)) 62: 63: (defrecord Ifgreater [e1 e2 e3 e4] 64: Evalable 65: (eval-under-env [e env] 66: (let [v1-test (eval-under-env (:e1 e) env) 67: v2-test (eval-under-env (:e2 e) env)] 68: (if (and (int? v1-test) (int? v2-test)) 69: (if (> (int-v v1-test) (int-v v2-test)) 70: (eval-under-env (:e3 e) env) 71: (eval-under-env (:e4 e) env)) 72: (throw (Exception. "MUPL ifgreater condition applied to non-number")))))) 73: (defn ifgreater [e1 e2 e3 e4] (Ifgreater. e1 e2 e3 e4)) 74: 75: (defrecord Mlet [var e body] 76: Evalable 77: (eval-under-env [e env] 78: (let [n (:var e) 79: v (:e e) 80: nenv (define-var n (eval-under-env v env) env)] 81: (eval-under-env (:body e) nenv)))) 82: (defn mlet [v e b] (Mlet. v e b)) 83: 84: (defrecord Call [fun arg] 85: Evalable 86: (eval-under-env [e env] 87: (let [c (eval-under-env (:fun e) env) 88: arg (eval-under-env (:arg e) env)] 89: (if (closure? c) 90: (let [fenv (closure-env c) 91: f (closure-fun c) 92: fname (fun-name f) 93: farg (fun-arg f) 94: fbody (fun-body f) 95: 96: ;; 添加环境，函数名和实参绑定 97: fenv (define-var farg arg fenv) 98: fenv (if fname (define-var fname c fenv) 99: fenv)] 100: (eval-under-env fbody fenv)) 101: (throw (Exception. "MUPL call apllied to non-closure")))))) 102: (defn call [f a] (Call. f a)) 103: 104: (defrecord Apair [e1 e2] 105: Evalable 106: (eval-under-env [e env] 107: (let [l (eval-under-env (:e1 e) env) 108: r (eval-under-env (:e2 e) env)] 109: (Apair. l r)))) 110: (defn apair [e1 e2] (Apair. e1 e2)) 111: (defn apair? [e] (instance? Apair e)) 112: (defn apair-l [e] (:e1 e)) 113: (defn apair-r [e] (:e2 e)) 114: 115: (defrecord Fst [e] 116: Evalable 117: (eval-under-env [e env] 118: (let [v (eval-under-env (:e e) env)] 119: (if (apair? v) 120: (apair-l v) 121: (throw (Exception. "MUPL fst apllied to non-pair")))))) 122: (defn fst [e] (Fst. e)) 123: 124: (defrecord Snd [e] 125: Evalable 126: (eval-under-env [e env] 127: (let [v (eval-under-env (:e e) env)] 128: (if (apair? v) 129: (apair-r v) 130: (throw (Exception. "MUPL snd apllied to non-pair")))))) 131: (defn snd [e] (Snd. e)) 132: 133: (defrecord Isaunit [e] 134: Evalable 135: (eval-under-env [e env] 136: (let [v (eval-under-env (:e e) env)] 137: (if (aunit? v) 138: (int 1) 139: (int 0))))) 140: (defn isaunit [e] (Isaunit. e)) 141: 142: (extend-type Object 143: Evalable 144: (eval-under-env [e _] (throw (Exception. (str "eval-exp expected an exp, but given:" e))))) 145: 146: (defn vec->mupllist 147: [xs] 148: (reduce #(apair %2 %1) (aunit) (rseq xs))) 149: 150: (defn mupllist->vec 151: [e] 152: (cond 153: (apair? e)(conj (mupllist->vec (apair-r e)) (apair-l e)) 154: (aunit? e) '() 155: :else (throw (Exception. "mupllist->vec not a valid mupl list")))) 156: 157: (defn eval-exp 158: [e] 159: (eval-under-env e {})) 160: 161: ;; 注意打印的时候没有显示record类型,但是是有类型的,显示为map 162: (eval-exp (add (int 3) (int 4))) 163: ;; => {:num 7} 164: 165: (eval-exp (ifgreater (int 3) (int 4) (int 3) (int 4))) 166: ;; => {:num 4} 167: 168: (eval-exp (ifgreater (int 5) (int 4) (int 5) (int 4))) 169: ;; => {:num 5} 170: 171: (eval-exp (mlet :x (int 1) (add (int 5) (variable :x)))) 172: ;; => {:num 6} 173: 174: (eval-exp (call (fun false "x" (add (variable "x") (int 8))) 175: (int 2))) 176: ;; => {:num 10} 177: 178: (eval-exp (snd (apair (int 1) (int 2)))) 179: ;; => {:num 2} 180: 181: (eval-exp (fst (apair (int 1) (int 2)))) 182: ;; => {:num 1} 183: 184: (eval-exp (isaunit (fun false "x" (aunit)))) 185: ;; => 0 186: 187: (eval-exp (isaunit (call (fun false "x" (aunit)) (int 0)))) 188: ;; => 1 189: 190: (defn ifaunit 191: [e1 e2 e3] 192: (ifgreater (isaunit e1) (int 0) e2 e3)) 193: (isaunit (int 0)) 194: (eval-exp (ifaunit (int 0) (int 3) (int 4))) 195: ;; => {:num 4} 196: 197: (def mupl-map (fun "map" "f" 198: (fun false "xs" 199: (ifaunit (variable "xs") 200: (aunit) 201: (apair (call (variable "f") (fst (variable "xs"))) 202: (call (call (variable "map") (variable "f")) 203: (snd (variable "xs")))))))) 204: 205: (eval-exp (call (call mupl-map (fun false "x" (add (variable "x") (int 1)))) 206: (vec->mupllist [(int 1) (int 2) (int 3)]))) 207: ;; => {:e1 {:num 2}, :e2 {:e1 {:num 3}, :e2 {:e1 {:num 4}, :e2 {}}}} 208: 209: (-> (eval-exp (call (call mupl-map (fun false "x" (add (variable "x") (int 1)))) 210: (vec->mupllist [(int 1) (int 2) (int 3)]))) 211: mupllist->vec) 212: ;; => ({:num 2} {:num 3} {:num 4})
Created: 2018-12-29 Sat 19:46