From ea81a8087bcd7953b083a2be9db447f75e7ebf56 Mon Sep 17 00:00:00 2001 From: Joel Martin Date: Wed, 2 Apr 2014 22:23:37 -0500 Subject: All: split types into types, env, printer, core. - types: low-level mapping to the implementation language. - core: functions on types that are exposed directly to mal. - printer: implementation called by pr-str, str, prn, println. - env: the environment implementation - Also, unindent all TCO while loops so that the diff of step4 and step5 are minimized. --- clojure/src/env.clj | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 clojure/src/env.clj (limited to 'clojure/src/env.clj') diff --git a/clojure/src/env.clj b/clojure/src/env.clj new file mode 100644 index 0000000..7f1f934 --- /dev/null +++ b/clojure/src/env.clj @@ -0,0 +1,35 @@ +(ns env) + +(defn env [& [outer binds exprs]] + ;;(prn "env" binds exprs) + ;; (when (not= (count binds) (count exprs)) + ;; (throw (Exception. "Arity mistmatch in env call"))) + (atom + (loop [env {:outer outer} + b binds + e exprs] + (cond + (= nil b) + env + + (= '& (first b)) + (assoc env (nth b 1) e) + + :else + (recur (assoc env (first b) (first e)) (next b) (next e)))))) + +(defn env-find [env k] + (cond + (contains? @env k) env + (:outer @env) (env-find (:outer @env) k) + :else nil)) + +(defn env-get [env k] + (let [e (env-find env k)] + (when-not e + (throw (Exception. (str "'" k "' not found")))) + (get @e k))) + +(defn env-set [env k v] + (swap! env assoc k v) + v) -- cgit v1.2.3