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.

15 files changed, 238 insertions, 197 deletions

diff --git a/clojure/Makefile b/clojure/Makefile
index d18eb50..4bc289e 100644
--- a/clojure/Makefile
+++ b/clojure/Makefile
@@ -1,7 +1,8 @@
 
 TESTS =
 
-SOURCES = src/types.clj src/readline.clj src/reader.clj src/stepA_more.clj
+SOURCES = src/readline.clj src/reader.clj src/printer.clj \
+	  src/env.clj src/core.clj src/stepA_more.clj
 
 all:
 
diff --git a/clojure/src/core.clj b/clojure/src/core.clj
new file mode 100644
index 0000000..23dfc55
--- /dev/null
+++ b/clojure/src/core.clj
@@ -0,0 +1,63 @@
+(ns core)
+
+;; Errors/exceptions
+(defn mal_throw [obj]
+  (throw (ex-info "mal exception" {:data obj})))
+
+;; Atoms
+(defn atom? [atm]
+  (= (type atm) clojure.lang.Atom))
+
+;; core_ns is core namespaces functions
+(def core_ns
+  [['= =]
+   ['throw mal_throw]
+   ['nil? nil?]
+   ['true? true?]
+   ['false? false?]
+   ['symbol? symbol?]
+   ['pr-str pr-str]
+   ['str str]
+   ['prn prn]
+   ['println println]
+   ['< <]
+   ['<= <=]
+   ['> >]
+   ['>= >=]
+   ['+ +]
+   ['- -]
+   ['* *]
+   ['/ /]
+  
+   ['list list]
+   ['list? seq?]
+   ['vector vector]
+   ['vector? vector?]
+   ['hash-map hash-map]
+   ['map? map?]
+   ['assoc assoc]
+   ['dissoc dissoc]
+   ['get get]
+   ['contains? contains?]
+   ['keys keys]
+   ['vals vals]
+   
+   ['sequential? sequential?]
+   ['cons cons]
+   ['concat concat]
+   ['nth nth]
+   ['first first]
+   ['rest rest]
+   ['empty? empty?]
+   ['count count]
+   ['conj conj]
+   ['apply apply]
+   ['map #(doall (map %1 %2))] 
+
+   ['with-meta with-meta]
+   ['meta meta]
+   ['atom atom]
+   ['atom? atom?]
+   ['deref deref]
+   ['reset! reset!]
+   ['swap! swap!]])
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)
diff --git a/clojure/src/printer.clj b/clojure/src/printer.clj
new file mode 100644
index 0000000..656914f
--- /dev/null
+++ b/clojure/src/printer.clj
@@ -0,0 +1,7 @@
+(ns printer)
+
+(defmethod clojure.core/print-method clojure.lang.Atom [a writer]
+  (.write writer "(atom ")
+  (.write writer (pr-str @a))
+  (.write writer ")"))
+
diff --git a/clojure/src/step1_read_print.clj b/clojure/src/step1_read_print.clj
index a99a0ed..31b2ac6 100644
--- a/clojure/src/step1_read_print.clj
+++ b/clojure/src/step1_read_print.clj
@@ -1,8 +1,8 @@
 (ns step1-read-print
     (:require [clojure.repl]
-              [types]
               [readline]
-              [reader]))
+              [reader]
+              [printer]))
 
 ;; read
 (defn READ [& [strng]]
diff --git a/clojure/src/step2_eval.clj b/clojure/src/step2_eval.clj
index 6ff9eb3..581bf3f 100644
--- a/clojure/src/step2_eval.clj
+++ b/clojure/src/step2_eval.clj
@@ -1,10 +1,8 @@
 (ns step2-eval
     (:require [clojure.repl]
-              [types]
               [readline]
-              [reader]))
-
-(declare EVAL)
+              [reader]
+              [printer]))
 
 ;; read
 (defn READ [& [strng]]
@@ -12,6 +10,7 @@
     (reader/read-string strng)))
 
 ;; eval
+(declare EVAL)
 (defn eval-ast [ast env]
   (cond
     (symbol? ast) (or (get env ast)
diff --git a/clojure/src/step3_env.clj b/clojure/src/step3_env.clj
index c0c4e8e..449bf79 100644
--- a/clojure/src/step3_env.clj
+++ b/clojure/src/step3_env.clj
@@ -1,10 +1,9 @@
 (ns step3-env
     (:require [clojure.repl]
-              [types]
               [readline]
-              [reader]))
-
-(declare EVAL)
+              [reader]
+              [printer]
+              [env]))
 
 ;; read
 (defn READ [& [strng]]
@@ -12,9 +11,10 @@
     (reader/read-string strng)))
 
 ;; eval
+(declare EVAL)
 (defn eval-ast [ast env]
   (cond
-    (symbol? ast) (types/env-get env ast)
+    (symbol? ast) (env/env-get env ast)
    
     (seq? ast)    (doall (map #(EVAL % env) ast))
 
@@ -34,12 +34,12 @@
     (let [[a0 a1 a2 a3] ast]
       (condp = a0
         'def!
-        (types/env-set env a1 (EVAL a2 env))
+        (env/env-set env a1 (EVAL a2 env))
 
         'let*
-        (let [let-env (types/env env)]
+        (let [let-env (env/env env)]
           (doseq [[b e] (partition 2 a1)]
-            (types/env-set let-env b (EVAL e let-env)))
+            (env/env-set let-env b (EVAL e let-env)))
           (EVAL a2 let-env))
 
         ;; apply
@@ -52,12 +52,12 @@
 (defn PRINT [exp] (pr-str exp))
 
 ;; repl
-(def repl-env (types/env))
+(def repl-env (env/env))
 (defn rep
   [strng]
   (PRINT (EVAL (READ strng), repl-env)))
 
-(defn _ref [k,v] (types/env-set repl-env k v))
+(defn _ref [k,v] (env/env-set repl-env k v))
 (_ref '+ +)
 (_ref '- -)
 (_ref '* *)
diff --git a/clojure/src/step4_if_fn_do.clj b/clojure/src/step4_if_fn_do.clj
index 4171848..b36f482 100644
--- a/clojure/src/step4_if_fn_do.clj
+++ b/clojure/src/step4_if_fn_do.clj
@@ -1,10 +1,10 @@
 (ns step4-if-fn-do
     (:require [clojure.repl]
-              [types]
               [readline]
-              [reader]))
-
-(declare EVAL)
+              [reader]
+              [printer]
+              [env]
+              [core]))
 
 ;; read
 (defn READ [& [strng]]
@@ -12,9 +12,10 @@
     (reader/read-string strng)))
 
 ;; eval
+(declare EVAL)
 (defn eval-ast [ast env]
   (cond
-    (symbol? ast) (types/env-get env ast)
+    (symbol? ast) (env/env-get env ast)
    
     (seq? ast)    (doall (map #(EVAL % env) ast))
 
@@ -34,12 +35,12 @@
     (let [[a0 a1 a2 a3] ast]
       (condp = a0
         'def!
-        (types/env-set env a1 (EVAL a2 env))
+        (env/env-set env a1 (EVAL a2 env))
 
         'let*
-        (let [let-env (types/env env)]
+        (let [let-env (env/env env)]
           (doseq [[b e] (partition 2 a1)]
-            (types/env-set let-env b (EVAL e let-env)))
+            (env/env-set let-env b (EVAL e let-env)))
           (EVAL a2 let-env))
 
         'do
@@ -55,7 +56,7 @@
 
         'fn*
         (fn [& args]
-          (EVAL a2 (types/env env a1 args)))
+          (EVAL a2 (env/env env a1 args)))
 
         ;; apply
         (let [el (eval-ast ast env)
@@ -67,15 +68,15 @@
 (defn PRINT [exp] (pr-str exp))
 
 ;; repl
-(def repl-env (types/env))
+(def repl-env (env/env))
 (defn rep
   [strng]
   (PRINT (EVAL (READ strng), repl-env)))
 
-(defn _ref [k,v] (types/env-set repl-env k v))
+(defn _ref [k,v] (env/env-set repl-env k v))
 
 ;; Import types related functions
-(doseq [[k v] types/types_ns] (_ref k v))
+(doseq [[k v] core/core_ns] (_ref k v))
 
 ;; Defined using the language itself
 (rep "(def! not (fn* [a] (if a false true)))")
diff --git a/clojure/src/step5_tco.clj b/clojure/src/step5_tco.clj
index 2ed07b4..7739029 100644
--- a/clojure/src/step5_tco.clj
+++ b/clojure/src/step5_tco.clj
@@ -1,10 +1,10 @@
 (ns step5-tco
     (:require [clojure.repl]
-              [types]
               [readline]
-              [reader]))
-
-(declare EVAL)
+              [reader]
+              [printer]
+              [env]
+              [core]))
 
 ;; read
 (defn READ [& [strng]]
@@ -12,9 +12,10 @@
     (reader/read-string strng)))
 
 ;; eval
+(declare EVAL)
 (defn eval-ast [ast env]
   (cond
-    (symbol? ast) (types/env-get env ast)
+    (symbol? ast) (env/env-get env ast)
    
     (seq? ast)    (doall (map #(EVAL % env) ast))
 
@@ -36,12 +37,12 @@
       (let [[a0 a1 a2 a3] ast]
         (condp = a0
           'def!
-          (types/env-set env a1 (EVAL a2 env))
+          (env/env-set env a1 (EVAL a2 env))
   
           'let*
-          (let [let-env (types/env env)]
+          (let [let-env (env/env env)]
             (doseq [[b e] (partition 2 a1)]
-              (types/env-set let-env b (EVAL e let-env)))
+              (env/env-set let-env b (EVAL e let-env)))
             (EVAL a2 let-env))
   
           'do
@@ -61,7 +62,7 @@
             :environment env
             :parameters a1}
           (fn [& args]
-            (EVAL a2 (types/env env a1 args)))
+            (EVAL a2 (env/env env a1 args)))
   
           ;; apply
           (let [el (eval-ast ast env)
@@ -69,22 +70,22 @@
                    args (rest el)
                    {:keys [expression environment parameters]} (meta f)]
             (if expression
-              (recur expression (types/env environment parameters args))
+              (recur expression (env/env environment parameters args))
               (apply f args))))))))
 
 ;; print
 (defn PRINT [exp] (pr-str exp))
 
 ;; repl
-(def repl-env (types/env))
+(def repl-env (env/env))
 (defn rep
   [strng]
   (PRINT (EVAL (READ strng), repl-env)))
 
-(defn _ref [k,v] (types/env-set repl-env k v))
+(defn _ref [k,v] (env/env-set repl-env k v))
 
 ;; Import types related functions
-(doseq [[k v] types/types_ns] (_ref k v))
+(doseq [[k v] core/core_ns] (_ref k v))
 
 ;; Defined using the language itself
 (rep "(def! not (fn* [a] (if a false true)))")
diff --git a/clojure/src/step6_file.clj b/clojure/src/step6_file.clj
index 2eb4e3d..a65b741 100644
--- a/clojure/src/step6_file.clj
+++ b/clojure/src/step6_file.clj
@@ -1,10 +1,10 @@
 (ns step6-file
     (:require [clojure.repl]
-              [types]
               [readline]
-              [reader]))
-
-(declare EVAL)
+              [reader]
+              [printer]
+              [env]
+              [core]))
 
 ;; read
 (defn READ [& [strng]]
@@ -12,9 +12,10 @@
     (reader/read-string strng)))
 
 ;; eval
+(declare EVAL)
 (defn eval-ast [ast env]
   (cond
-    (symbol? ast) (types/env-get env ast)
+    (symbol? ast) (env/env-get env ast)
    
     (seq? ast)    (doall (map #(EVAL % env) ast))
 
@@ -36,12 +37,12 @@
       (let [[a0 a1 a2 a3] ast]
         (condp = a0
           'def!
-          (types/env-set env a1 (EVAL a2 env))
+          (env/env-set env a1 (EVAL a2 env))
   
           'let*
-          (let [let-env (types/env env)]
+          (let [let-env (env/env env)]
             (doseq [[b e] (partition 2 a1)]
-              (types/env-set let-env b (EVAL e let-env)))
+              (env/env-set let-env b (EVAL e let-env)))
             (EVAL a2 let-env))
   
           'do
@@ -61,7 +62,7 @@
             :environment env
             :parameters a1}
           (fn [& args]
-            (EVAL a2 (types/env env a1 args)))
+            (EVAL a2 (env/env env a1 args)))
   
           ;; apply
           (let [el (eval-ast ast env)
@@ -69,22 +70,22 @@
                    args (rest el)
                    {:keys [expression environment parameters]} (meta f)]
             (if expression
-              (recur expression (types/env environment parameters args))
+              (recur expression (env/env environment parameters args))
               (apply f args))))))))
 
 ;; print
 (defn PRINT [exp] (pr-str exp))
 
 ;; repl
-(def repl-env (types/env))
+(def repl-env (env/env))
 (defn rep
   [strng]
-  (PRINT (EVAL (READ strng), repl-env)))
+  (PRINT (EVAL (READ strng) repl-env)))
 
-(defn _ref [k,v] (types/env-set repl-env k v))
+(defn _ref [k,v] (env/env-set repl-env k v))
 
 ;; Import types related functions
-(doseq [[k v] types/types_ns] (_ref k v))
+(doseq [[k v] core/core_ns] (_ref k v))
 
 ;; Defined using the language itself
 (_ref 'read-string reader/read-string)
diff --git a/clojure/src/step7_quote.clj b/clojure/src/step7_quote.clj
index 398b7d2..e68a4cc 100644
--- a/clojure/src/step7_quote.clj
+++ b/clojure/src/step7_quote.clj
@@ -1,10 +1,10 @@
 (ns step7-quote
     (:require [clojure.repl]
-              [types]
               [readline]
-              [reader]))
-
-(declare EVAL)
+              [reader]
+              [printer]
+              [env]
+              [core]))
 
 ;; read
 (defn READ [& [strng]]
@@ -12,6 +12,7 @@
     (reader/read-string strng)))
 
 ;; eval
+(declare EVAL)
 (defn is-pair [x]
   (and (sequential? x) (> (count x) 0)))
 
@@ -31,7 +32,7 @@
 
 (defn eval-ast [ast env]
   (cond
-    (symbol? ast) (types/env-get env ast)
+    (symbol? ast) (env/env-get env ast)
    
     (seq? ast)    (doall (map #(EVAL % env) ast))
 
@@ -53,12 +54,12 @@
       (let [[a0 a1 a2 a3] ast]
         (condp = a0
           'def!
-          (types/env-set env a1 (EVAL a2 env))
+          (env/env-set env a1 (EVAL a2 env))
   
           'let*
-          (let [let-env (types/env env)]
+          (let [let-env (env/env env)]
             (doseq [[b e] (partition 2 a1)]
-              (types/env-set let-env b (EVAL e let-env)))
+              (env/env-set let-env b (EVAL e let-env)))
             (EVAL a2 let-env))
 
           'quote
@@ -84,7 +85,7 @@
             :environment env
             :parameters a1}
           (fn [& args]
-            (EVAL a2 (types/env env a1 args)))
+            (EVAL a2 (env/env env a1 args)))
   
           ;; apply
           (let [el (eval-ast ast env)
@@ -92,22 +93,22 @@
                    args (rest el)
                    {:keys [expression environment parameters]} (meta f)]
             (if expression
-              (recur expression (types/env environment parameters args))
+              (recur expression (env/env environment parameters args))
               (apply f args))))))))
 
 ;; print
 (defn PRINT [exp] (pr-str exp))
 
 ;; repl
-(def repl-env (types/env))
+(def repl-env (env/env))
 (defn rep
   [strng]
   (PRINT (EVAL (READ strng) repl-env)))
 
-(defn _ref [k,v] (types/env-set repl-env k v))
+(defn _ref [k,v] (env/env-set repl-env k v))
 
 ;; Import types related functions
-(doseq [[k v] types/types_ns] (_ref k v))
+(doseq [[k v] core/core_ns] (_ref k v))
 
 ;; Defined using the language itself
 (_ref 'read-string reader/read-string)
diff --git a/clojure/src/step8_macros.clj b/clojure/src/step8_macros.clj
index 6b696e7..ed5638b 100644
--- a/clojure/src/step8_macros.clj
+++ b/clojure/src/step8_macros.clj
@@ -1,11 +1,11 @@
 (ns step8-macros
     (:refer-clojure :exclude [macroexpand])
     (:require [clojure.repl]
-              [types]
               [readline]
-              [reader]))
-
-(declare EVAL)
+              [reader]
+              [printer]
+              [env]
+              [core]))
 
 ;; read
 (defn READ [& [strng]]
@@ -13,6 +13,7 @@
     (reader/read-string strng)))
 
 ;; eval
+(declare EVAL)
 (defn is-pair [x]
   (and (sequential? x) (> (count x) 0)))
 
@@ -33,19 +34,19 @@
 (defn is-macro-call [ast env]
   (and (seq? ast)
        (symbol? (first ast))
-       (types/env-find env (first ast))
-       (:ismacro (meta (types/env-get env (first ast))))))
+       (env/env-find env (first ast))
+       (:ismacro (meta (env/env-get env (first ast))))))
 
 (defn macroexpand [ast env]
   (loop [ast ast]
     (if (is-macro-call ast env)
-      (let [mac (types/env-get env (first ast))]
+      (let [mac (env/env-get env (first ast))]
         (recur (apply mac (rest ast))))
       ast)))
 
 (defn eval-ast [ast env]
   (cond
-    (symbol? ast) (types/env-get env ast)
+    (symbol? ast) (env/env-get env ast)
    
     (seq? ast)    (doall (map #(EVAL % env) ast))
 
@@ -71,12 +72,12 @@
           (let [[a0 a1 a2 a3] ast]
             (condp = a0
               'def!
-              (types/env-set env a1 (EVAL a2 env))
+              (env/env-set env a1 (EVAL a2 env))
       
               'let*
-              (let [let-env (types/env env)]
+              (let [let-env (env/env env)]
                 (doseq [[b e] (partition 2 a1)]
-                  (types/env-set let-env b (EVAL e let-env)))
+                  (env/env-set let-env b (EVAL e let-env)))
                 (EVAL a2 let-env))
     
               'quote
@@ -88,7 +89,7 @@
               'defmacro!
               (let [func (with-meta (EVAL a2 env)
                                     {:ismacro true})]
-                (types/env-set env a1 func))
+                (env/env-set env a1 func))
     
               'macroexpand
               (macroexpand a1 env)
@@ -110,7 +111,7 @@
                 :environment env
                 :parameters a1}
               (fn [& args]
-                (EVAL a2 (types/env env a1 args)))
+                (EVAL a2 (env/env env a1 args)))
       
               ;; apply
               (let [el (eval-ast ast env)
@@ -118,22 +119,22 @@
                        args (rest el)
                        {:keys [expression environment parameters]} (meta f)]
                 (if expression
-                  (recur expression (types/env environment parameters args))
+                  (recur expression (env/env environment parameters args))
                   (apply f args))))))))))
 
 ;; print
 (defn PRINT [exp] (pr-str exp))
 
 ;; repl
-(def repl-env (types/env))
+(def repl-env (env/env))
 (defn rep
   [strng]
   (PRINT (EVAL (READ strng) repl-env)))
 
-(defn _ref [k,v] (types/env-set repl-env k v))
+(defn _ref [k,v] (env/env-set repl-env k v))
 
 ;; Import types related functions
-(doseq [[k v] types/types_ns] (_ref k v))
+(doseq [[k v] core/core_ns] (_ref k v))
 
 ;; Defined using the language itself
 (_ref 'read-string reader/read-string)
diff --git a/clojure/src/step9_interop.clj b/clojure/src/step9_interop.clj
index d78aed7..da37574 100644
--- a/clojure/src/step9_interop.clj
+++ b/clojure/src/step9_interop.clj
@@ -1,11 +1,11 @@
 (ns step9-interop
     (:refer-clojure :exclude [macroexpand])
     (:require [clojure.repl]
-              [types]
               [readline]
-              [reader]))
-
-(declare EVAL)
+              [reader]
+              [printer]
+              [env]
+              [core]))
 
 ;; read
 (defn READ [& [strng]]
@@ -13,6 +13,7 @@
     (reader/read-string strng)))
 
 ;; eval
+(declare EVAL)
 (defn is-pair [x]
   (and (sequential? x) (> (count x) 0)))
 
@@ -33,19 +34,19 @@
 (defn is-macro-call [ast env]
   (and (seq? ast)
        (symbol? (first ast))
-       (types/env-find env (first ast))
-       (:ismacro (meta (types/env-get env (first ast))))))
+       (env/env-find env (first ast))
+       (:ismacro (meta (env/env-get env (first ast))))))
 
 (defn macroexpand [ast env]
   (loop [ast ast]
     (if (is-macro-call ast env)
-      (let [mac (types/env-get env (first ast))]
+      (let [mac (env/env-get env (first ast))]
         (recur (apply mac (rest ast))))
       ast)))
 
 (defn eval-ast [ast env]
   (cond
-    (symbol? ast) (types/env-get env ast)
+    (symbol? ast) (env/env-get env ast)
    
     (seq? ast)    (doall (map #(EVAL % env) ast))
 
@@ -71,12 +72,12 @@
           (let [[a0 a1 a2 a3] ast]
             (condp = a0
               'def!
-              (types/env-set env a1 (EVAL a2 env))
+              (env/env-set env a1 (EVAL a2 env))
       
               'let*
-              (let [let-env (types/env env)]
+              (let [let-env (env/env env)]
                 (doseq [[b e] (partition 2 a1)]
-                  (types/env-set let-env b (EVAL e let-env)))
+                  (env/env-set let-env b (EVAL e let-env)))
                 (EVAL a2 let-env))
     
               'quote
@@ -88,7 +89,7 @@
               'defmacro!
               (let [func (with-meta (EVAL a2 env)
                                     {:ismacro true})]
-                (types/env-set env a1 func))
+                (env/env-set env a1 func))
     
               'macroexpand
               (macroexpand a1 env)
@@ -113,7 +114,7 @@
                 :environment env
                 :parameters a1}
               (fn [& args]
-                (EVAL a2 (types/env env a1 args)))
+                (EVAL a2 (env/env env a1 args)))
       
               ;; apply
               (let [el (eval-ast ast env)
@@ -121,22 +122,22 @@
                        args (rest el)
                        {:keys [expression environment parameters]} (meta f)]
                 (if expression
-                  (recur expression (types/env environment parameters args))
+                  (recur expression (env/env environment parameters args))
                   (apply f args))))))))))
 
 ;; print
 (defn PRINT [exp] (pr-str exp))
 
 ;; repl
-(def repl-env (types/env))
+(def repl-env (env/env))
 (defn rep
   [strng]
   (PRINT (EVAL (READ strng) repl-env)))
 
-(defn _ref [k,v] (types/env-set repl-env k v))
+(defn _ref [k,v] (env/env-set repl-env k v))
 
 ;; Import types related functions
-(doseq [[k v] types/types_ns] (_ref k v))
+(doseq [[k v] core/core_ns] (_ref k v))
 
 ;; Defined using the language itself
 (_ref 'read-string reader/read-string)
diff --git a/clojure/src/stepA_more.clj b/clojure/src/stepA_more.clj
index d5d80bf..77b8cd7 100644
--- a/clojure/src/stepA_more.clj
+++ b/clojure/src/stepA_more.clj
@@ -1,11 +1,11 @@
 (ns stepA-more
     (:refer-clojure :exclude [macroexpand])
     (:require [clojure.repl]
-              [types]
               [readline]
-              [reader]))
-
-(declare EVAL)
+              [reader]
+              [printer]
+              [env]
+              [core]))
 
 ;; read
 (defn READ [& [strng]]
@@ -13,6 +13,7 @@
     (reader/read-string strng)))
 
 ;; eval
+(declare EVAL)
 (defn is-pair [x]
   (and (sequential? x) (> (count x) 0)))
 
@@ -33,19 +34,19 @@
 (defn is-macro-call [ast env]
   (and (seq? ast)
        (symbol? (first ast))
-       (types/env-find env (first ast))
-       (:ismacro (meta (types/env-get env (first ast))))))
+       (env/env-find env (first ast))
+       (:ismacro (meta (env/env-get env (first ast))))))
 
 (defn macroexpand [ast env]
   (loop [ast ast]
     (if (is-macro-call ast env)
-      (let [mac (types/env-get env (first ast))]
+      (let [mac (env/env-get env (first ast))]
         (recur (apply mac (rest ast))))
       ast)))
 
 (defn eval-ast [ast env]
   (cond
-    (symbol? ast) (types/env-get env ast)
+    (symbol? ast) (env/env-get env ast)
    
     (seq? ast)    (doall (map #(EVAL % env) ast))
 
@@ -71,12 +72,12 @@
           (let [[a0 a1 a2 a3] ast]
             (condp = a0
               'def!
-              (types/env-set env a1 (EVAL a2 env))
+              (env/env-set env a1 (EVAL a2 env))
       
               'let*
-              (let [let-env (types/env env)]
+              (let [let-env (env/env env)]
                 (doseq [[b e] (partition 2 a1)]
-                  (types/env-set let-env b (EVAL e let-env)))
+                  (env/env-set let-env b (EVAL e let-env)))
                 (EVAL a2 let-env))
     
               'quote
@@ -88,7 +89,7 @@
               'defmacro!
               (let [func (with-meta (EVAL a2 env)
                                     {:ismacro true})]
-                (types/env-set env a1 func))
+                (env/env-set env a1 func))
     
               'macroexpand
               (macroexpand a1 env)
@@ -101,13 +102,13 @@
                 (try
                   (EVAL a1 env)
                   (catch clojure.lang.ExceptionInfo ei
-                    (EVAL (nth a2 2) (types/env env
-                                                [(nth a2 1)]
-                                                [(:data (ex-data ei))])))
+                    (EVAL (nth a2 2) (env/env env
+                                              [(nth a2 1)]
+                                              [(:data (ex-data ei))])))
                   (catch Throwable t
-                    (EVAL (nth a2 2) (types/env env
-                                                [(nth a2 1)]
-                                                [(.getMessage t)]))))
+                    (EVAL (nth a2 2) (env/env env
+                                              [(nth a2 1)]
+                                              [(.getMessage t)]))))
                 (EVAL a1 env))
     
               'do
@@ -127,7 +128,7 @@
                 :environment env
                 :parameters a1}
               (fn [& args]
-                (EVAL a2 (types/env env a1 args)))
+                (EVAL a2 (env/env env a1 args)))
       
               ;; apply
               (let [el (eval-ast ast env)
@@ -135,22 +136,22 @@
                        args (rest el)
                        {:keys [expression environment parameters]} (meta f)]
                 (if expression
-                  (recur expression (types/env environment parameters args))
+                  (recur expression (env/env environment parameters args))
                   (apply f args))))))))))
 
 ;; print
 (defn PRINT [exp] (pr-str exp))
 
 ;; repl
-(def repl-env (types/env))
+(def repl-env (env/env))
 (defn rep
   [strng]
   (PRINT (EVAL (READ strng) repl-env)))
 
-(defn _ref [k,v] (types/env-set repl-env k v))
+(defn _ref [k,v] (env/env-set repl-env k v))
 
 ;; Import types related functions
-(doseq [[k v] types/types_ns] (_ref k v))
+(doseq [[k v] core/core_ns] (_ref k v))
 
 ;; Defined using the language itself
 (_ref 'readline readline/readline)
diff --git a/clojure/src/types.clj b/clojure/src/types.clj
deleted file mode 100644
index 922cf79..0000000
--- a/clojure/src/types.clj
+++ /dev/null
@@ -1,71 +0,0 @@
-(ns types)
-
-;; Custom printing
-
-(defmethod clojure.core/print-method clojure.lang.Atom [a writer]
-  (.write writer "(atom ")
-  (.write writer (pr-str @a))
-  (.write writer ")"))
-
-;; Errors/exceptions
-(defn mal_throw [obj]
-  (throw (ex-info "mal exception" {:data obj})))
-
-
-;; Atoms
-(defn atom? [atm]
-  (= (type atm) clojure.lang.Atom))
-
-
-;; 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)
-
-(def types_ns
-  [['pr-str pr-str] ['str str] ['prn prn] ['println println]
-   ['with-meta with-meta] ['meta meta] ['= =]
-   ['nil? nil?] ['true? true?] ['false? false?] ['symbol? symbol?]
-   ['> >] ['>= >=] ['< <] ['<= <=] ['+ +] ['- -] ['* *] ['/ /]
-   ['hash-map hash-map] ['map? map?]
-   ['assoc assoc] ['dissoc dissoc] ['get get]
-   ['contains? contains?] ['keys keys] ['vals vals]
-   ['throw mal_throw]
-   ['list list] ['list? seq?] ['vector vector] ['vector? vector?]
-   ['atom atom] ['atom? atom?] ['deref deref]
-   ['reset! reset!] ['swap! swap!]
-   ['sequential? sequential?] ['cons cons] ['nth nth]
-   ['empty? empty?] ['count count] ['concat concat]
-   ['conj conj] ['first first] ['rest rest]
-   ['apply apply] ['map #(doall (map %1 %2))]])