Fix metadata on functions.

- Don't use metadata to store ast, env, params data.
- In Clojure, store metadata on the :meta key of the real metadata.
  This also allows using any datatype as metadata.

8 files changed, 32 insertions, 30 deletions

diff --git a/python/core.py b/python/core.py
index 28d9c5e..5e2ef75 100644
--- a/python/core.py
+++ b/python/core.py
@@ -85,7 +85,10 @@ def mapf(f, lst): return List(map(f, lst))
 
 # Metadata functions
 def with_meta(obj, meta):
-    new_obj = copy.copy(obj)
+    if type(obj) == type(lambda x:x):
+        new_obj = obj.__copy__()
+    else:
+        new_obj = copy.copy(obj)
     new_obj.__meta__ = meta
     return new_obj
 
diff --git a/python/mal_types.py b/python/mal_types.py
index 15e4b6b..74409c9 100644
--- a/python/mal_types.py
+++ b/python/mal_types.py
@@ -38,11 +38,16 @@ def _symbol(str): return Symbol(str)
 def _symbol_Q(exp): return type(exp) == Symbol
 
 # Functions
-def _function(Eval, Env, exp, env, params):
-    def f(*args):
-        return Eval(exp, Env(env, params, args))
-    f.__meta__ = {"exp": exp, "env": env, "params": params}
-    return f
+def _function(Eval, Env, ast, env, params):
+    def gen_fn():
+        def fn(*args):
+            return Eval(ast, Env(env, params, args))
+        fn.__meta__ = None
+        fn.__ast__ = ast
+        fn.__gen_env__ = lambda args: Env(env, params, args)
+        fn.__copy__ = gen_fn
+        return fn
+    return gen_fn()
 def _function_Q(f): return type(f) == type(function_Q)
 
 # lists
diff --git a/python/step5_tco.py b/python/step5_tco.py
index 4335a96..d9d34bc 100644
--- a/python/step5_tco.py
+++ b/python/step5_tco.py
@@ -65,10 +65,9 @@ def EVAL(ast, env):
         else:
             el = eval_ast(ast, env)
             f = el[0]
-            if hasattr(f, '__meta__') and f.__meta__.has_key("exp"):
-                m = f.__meta__
-                ast = m['exp']
-                env = Env(m['env'], m['params'], el[1:])
+            if hasattr(f, '__ast__'):
+                ast = f.__ast__
+                env = f.__gen_env__(el[1:])
             else:
                 return f(*el[1:])
 
diff --git a/python/step6_file.py b/python/step6_file.py
index 9e0b8cd..f3847d2 100644
--- a/python/step6_file.py
+++ b/python/step6_file.py
@@ -65,10 +65,9 @@ def EVAL(ast, env):
         else:
             el = eval_ast(ast, env)
             f = el[0]
-            if hasattr(f, '__meta__') and f.__meta__.has_key("exp"):
-                m = f.__meta__
-                ast = m['exp']
-                env = Env(m['env'], m['params'], el[1:])
+            if hasattr(f, '__ast__'):
+                ast = f.__ast__
+                env = f.__gen_env__(el[1:])
             else:
                 return f(*el[1:])
 
diff --git a/python/step7_quote.py b/python/step7_quote.py
index 3ed6965..f57dc0a 100644
--- a/python/step7_quote.py
+++ b/python/step7_quote.py
@@ -87,10 +87,9 @@ def EVAL(ast, env):
         else:
             el = eval_ast(ast, env)
             f = el[0]
-            if hasattr(f, '__meta__') and f.__meta__.has_key("exp"):
-                m = f.__meta__
-                ast = m['exp']
-                env = Env(m['env'], m['params'], el[1:])
+            if hasattr(f, '__ast__'):
+                ast = f.__ast__
+                env = f.__gen_env__(el[1:])
             else:
                 return f(*el[1:])
 
diff --git a/python/step8_macros.py b/python/step8_macros.py
index 6e2bd45..5d9151a 100644
--- a/python/step8_macros.py
+++ b/python/step8_macros.py
@@ -107,10 +107,9 @@ def EVAL(ast, env):
         else:
             el = eval_ast(ast, env)
             f = el[0]
-            if hasattr(f, '__meta__') and f.__meta__.has_key("exp"):
-                m = f.__meta__
-                ast = m['exp']
-                env = Env(m['env'], m['params'], el[1:])
+            if hasattr(f, '__ast__'):
+                ast = f.__ast__
+                env = f.__gen_env__(el[1:])
             else:
                 return f(*el[1:])
 
diff --git a/python/step9_interop.py b/python/step9_interop.py
index 66a8c50..521a3c2 100644
--- a/python/step9_interop.py
+++ b/python/step9_interop.py
@@ -116,10 +116,9 @@ def EVAL(ast, env):
         else:
             el = eval_ast(ast, env)
             f = el[0]
-            if hasattr(f, '__meta__') and f.__meta__.has_key("exp"):
-                m = f.__meta__
-                ast = m['exp']
-                env = Env(m['env'], m['params'], el[1:])
+            if hasattr(f, '__ast__'):
+                ast = f.__ast__
+                env = f.__gen_env__(el[1:])
             else:
                 return f(*el[1:])
 
diff --git a/python/stepA_more.py b/python/stepA_more.py
index 7c6a5da..21c1641 100644
--- a/python/stepA_more.py
+++ b/python/stepA_more.py
@@ -127,10 +127,9 @@ def EVAL(ast, env):
         else:
             el = eval_ast(ast, env)
             f = el[0]
-            if hasattr(f, '__meta__') and f.__meta__.has_key("exp"):
-                m = f.__meta__
-                ast = m['exp']
-                env = Env(m['env'], m['params'], el[1:])
+            if hasattr(f, '__ast__'):
+                ast = f.__ast__
+                env = f.__gen_env__(el[1:])
             else:
                 return f(*el[1:])