rpython: complete the eval_ast merge, add DEBUG-EVAL

impls/rpython/env.py

@@ -21,20 +21,17 @@ def __init__(self, outer=None, binds=None, exprs=None):
                 else:
                     self.data[bind.value] = exprs[i]
 
-    def find(self, key):
-        assert isinstance(key, MalSym)
-        if key.value in self.data: return self
-        elif self.outer:           return self.outer.find(key)
-        else:                      return None
-
     def set(self, key, value):
         assert isinstance(key, MalSym)
         assert isinstance(value, MalType)
         self.data[key.value] = value
         return value
 
     def get(self, key):
-        assert isinstance(key, MalSym)
-        env = self.find(key)
-        if not env: throw_str("'" + str(key.value) + "' not found")
-        return env.data[key.value]
+        assert isinstance(key, unicode)
+        env = self
+        while key not in env.data:
+            env = env.outer
+            if env is None:
+                return None
+        return env.data[key]

impls/rpython/step2_eval.py

@@ -11,18 +11,14 @@ def READ(str):
     return reader.read_str(str)
 
 # eval
-def eval_ast(ast, env):
+def EVAL(ast, env):
+    # print(u"EVAL " + printer._pr_str(ast))
     if types._symbol_Q(ast):
         assert isinstance(ast, MalSym)
         if ast.value in env:
             return env[ast.value]
         else:
-            raise Exception(u"'" + ast.value + u"' not found")
-    elif types._list_Q(ast):
-        res = []
-        for a in ast.values:
-            res.append(EVAL(a, env))
-        return MalList(res)
+            raise Exception("'" + ast.value + "' not found")
     elif types._vector_Q(ast):
         res = []
         for a in ast.values:
@@ -33,20 +29,18 @@ def eval_ast(ast, env):
         for k in ast.dct.keys():
             new_dct[k] = EVAL(ast.dct[k], env)
         return MalHashMap(new_dct)
-    else:
+    elif not types._list_Q(ast):
         return ast  # primitive value, return unchanged
-
-def EVAL(ast, env):
-        #print("EVAL %s" % printer._pr_str(ast))
-        if not types._list_Q(ast):
-            return eval_ast(ast, env)
-
+    else:
         # apply list
         if len(ast) == 0: return ast
-        el = eval_ast(ast, env)
-        f = el.values[0]
+        a0 = ast[0]
+        f = EVAL(a0, env)
+        args = []
+        for i in range(1, len(ast)):
+            args.append(EVAL(ast[i], env))
         if isinstance(f, MalFunc):
-            return f.apply(el.values[1:])
+            return f.apply(args)
         else:
             raise Exception("%s is not callable" % f)
 
@@ -55,7 +49,7 @@ def PRINT(exp):
     return printer._pr_str(exp)
 
 # repl
-repl_env = {} 
+repl_env = {}
 def REP(str, env):
     return PRINT(EVAL(READ(str), env))
 

impls/rpython/step3_env.py

@@ -2,7 +2,7 @@
 import mal_readline
 import mal_types as types
 from mal_types import (MalSym, MalInt, MalStr,
-                       _symbol, _keywordu,
+                       nil, false, _symbol, _keywordu, throw_str,
                        MalList, _list, MalVector, MalHashMap, MalFunc)
 import reader, printer
 from env import Env
@@ -12,15 +12,11 @@ def READ(str):
     return reader.read_str(str)
 
 # eval
-def eval_ast(ast, env):
+def EVAL(ast, env):
+    if env.get(u"DEBUG-EVAL") not in (None, nil, false):
+        print(u"EVAL " + printer._pr_str(ast))
     if types._symbol_Q(ast):
-        assert isinstance(ast, MalSym)
-        return env.get(ast)
-    elif types._list_Q(ast):
-        res = []
-        for a in ast.values:
-            res.append(EVAL(a, env))
-        return MalList(res)
+        return env.get(ast.value) or throw_str("'" + ast.value + "' not found")
     elif types._vector_Q(ast):
         res = []
         for a in ast.values:
@@ -31,35 +27,34 @@ def eval_ast(ast, env):
         for k in ast.dct.keys():
             new_dct[k] = EVAL(ast.dct[k], env)
         return MalHashMap(new_dct)
-    else:
+    elif not types._list_Q(ast):
         return ast  # primitive value, return unchanged
-
-def EVAL(ast, env):
-        #print("EVAL %s" % printer._pr_str(ast))
-        if not types._list_Q(ast):
-            return eval_ast(ast, env)
-
+    else:
         # apply list
         if len(ast) == 0: return ast
         a0 = ast[0]
-        if not isinstance(a0, MalSym):
+        if isinstance(a0, MalSym):
+            a0sym = a0.value
+        else:
             raise Exception("attempt to apply on non-symbol")
 
-        if u"def!" == a0.value:
+        if u"def!" == a0sym:
             a1, a2 = ast[1], ast[2]
             res = EVAL(a2, env)
             return env.set(a1, res)
-        elif u"let*" == a0.value:
+        elif u"let*" == a0sym:
             a1, a2 = ast[1], ast[2]
             let_env = Env(env)
             for i in range(0, len(a1), 2):
                 let_env.set(a1[i], EVAL(a1[i+1], let_env))
             return EVAL(a2, let_env)
         else:
-            el = eval_ast(ast, env)
-            f = el.values[0]
+            f = EVAL(a0, env)
+            args = []
+            for i in range(1, len(ast)):
+                args.append(EVAL(ast[i], env))
             if isinstance(f, MalFunc):
-                return f.apply(el.values[1:])
+                return f.apply(args)
             else:
                 raise Exception("%s is not callable" % f)
 

impls/rpython/step4_if_fn_do.py

@@ -2,7 +2,7 @@
 import mal_readline
 import mal_types as types
 from mal_types import (MalSym, MalInt, MalStr,
-                       nil, true, false, _symbol, _keywordu,
+                       nil, true, false, _symbol, _keywordu, throw_str,
                        MalList, _list, MalVector, MalHashMap, MalFunc)
 import reader, printer
 from env import Env
@@ -13,15 +13,11 @@ def READ(str):
     return reader.read_str(str)
 
 # eval
-def eval_ast(ast, env):
+def EVAL(ast, env):
+    if env.get(u"DEBUG-EVAL") not in (None, nil, false):
+        print(u"EVAL " + printer._pr_str(ast))
     if types._symbol_Q(ast):
-        assert isinstance(ast, MalSym)
-        return env.get(ast)
-    elif types._list_Q(ast):
-        res = []
-        for a in ast.values:
-            res.append(EVAL(a, env))
-        return MalList(res)
+        return env.get(ast.value) or throw_str("'" + ast.value + "' not found")
     elif types._vector_Q(ast):
         res = []
         for a in ast.values:
@@ -32,14 +28,9 @@ def eval_ast(ast, env):
         for k in ast.dct.keys():
             new_dct[k] = EVAL(ast.dct[k], env)
         return MalHashMap(new_dct)
-    else:
+    elif not types._list_Q(ast):
         return ast  # primitive value, return unchanged
-
-def EVAL(ast, env):
-        #print("EVAL %s" % printer._pr_str(ast))
-        if not types._list_Q(ast):
-            return eval_ast(ast, env)
-
+    else:
         # apply list
         if len(ast) == 0: return ast
         a0 = ast[0]
@@ -59,8 +50,11 @@ def EVAL(ast, env):
                 let_env.set(a1[i], EVAL(a1[i+1], let_env))
             return EVAL(a2, let_env)
         elif u"do" == a0sym:
-            el = eval_ast(ast.rest(), env)
-            return el.values[-1]
+            if len(ast) == 0:
+                return nil
+            for i in range(1, len(ast) - 1):
+                EVAL(ast[i], env)
+            return EVAL(ast[-1], env)
         elif u"if" == a0sym:
             a1, a2 = ast[1], ast[2]
             cond = EVAL(a1, env)
@@ -73,10 +67,12 @@ def EVAL(ast, env):
             a1, a2 = ast[1], ast[2]
             return MalFunc(None, a2, env, a1, EVAL)
         else:
-            el = eval_ast(ast, env)
-            f = el.values[0]
+            f = EVAL(a0, env)
+            args = []
+            for i in range(1, len(ast)):
+                args.append(EVAL(ast[i], env))
             if isinstance(f, MalFunc):
-                return f.apply(el.rest())
+                return f.apply(args)
             else:
                 raise Exception("%s is not callable" % f)
 

impls/rpython/step5_tco.py

@@ -2,7 +2,7 @@
 import mal_readline
 import mal_types as types
 from mal_types import (MalSym, MalInt, MalStr,
-                       nil, true, false, _symbol, _keywordu,
+                       nil, true, false, _symbol, _keywordu, throw_str,
                        MalList, _list, MalVector, MalHashMap, MalFunc)
 import reader, printer
 from env import Env
@@ -13,15 +13,12 @@ def READ(str):
     return reader.read_str(str)
 
 # eval
-def eval_ast(ast, env):
+def EVAL(ast, env):
+  while True:
+    if env.get(u"DEBUG-EVAL") not in (None, nil, false):
+        print(u"EVAL " + printer._pr_str(ast))
     if types._symbol_Q(ast):
-        assert isinstance(ast, MalSym)
-        return env.get(ast)
-    elif types._list_Q(ast):
-        res = []
-        for a in ast.values:
-            res.append(EVAL(a, env))
-        return MalList(res)
+        return env.get(ast.value) or throw_str("'" + ast.value + "' not found")
     elif types._vector_Q(ast):
         res = []
         for a in ast.values:
@@ -32,15 +29,9 @@ def eval_ast(ast, env):
         for k in ast.dct.keys():
             new_dct[k] = EVAL(ast.dct[k], env)
         return MalHashMap(new_dct)
-    else:
+    elif not types._list_Q(ast):
         return ast  # primitive value, return unchanged
-
-def EVAL(ast, env):
-    while True:
-        #print("EVAL %s" % printer._pr_str(ast))
-        if not types._list_Q(ast):
-            return eval_ast(ast, env)
-
+    else:
         # apply list
         if len(ast) == 0: return ast
         a0 = ast[0]
@@ -63,8 +54,8 @@ def EVAL(ast, env):
         elif u"do" == a0sym:
             if len(ast) == 0:
                 return nil
-            elif len(ast) > 1:
-                eval_ast(ast.slice2(1, len(ast)-1), env)
+            for i in range(1, len(ast) - 1):
+                EVAL(ast[i], env)
             ast = ast[-1] # Continue loop (TCO)
         elif u"if" == a0sym:
             a1, a2 = ast[1], ast[2]
@@ -78,14 +69,16 @@ def EVAL(ast, env):
             a1, a2 = ast[1], ast[2]
             return MalFunc(None, a2, env, a1, EVAL)
         else:
-            el = eval_ast(ast, env)
-            f = el.values[0]
+            f = EVAL(a0, env)
+            args = []
+            for i in range(1, len(ast)):
+                args.append(EVAL(ast[i], env))
             if isinstance(f, MalFunc):
                 if f.ast:
                     ast = f.ast
-                    env = f.gen_env(el.rest()) # Continue loop (TCO) 
+                    env = f.gen_env(args) # Continue loop (TCO)
                 else:
-                    return f.apply(el.rest())
+                    return f.apply(args)
             else:
                 raise Exception("%s is not callable" % f)