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.

1 files changed, 7 insertions, 9 deletions

diff --git a/python/step1_read_print.py b/python/step1_read_print.py
index 165dfa3..0315cf0 100644
--- a/python/step1_read_print.py
+++ b/python/step1_read_print.py
@@ -1,21 +1,19 @@
 import sys, traceback
 import mal_readline
-from mal_types import (pr_str, sequential_Q, symbol_Q, coll_Q, list_Q,
-                       vector_Q, hash_map_Q, new_symbol, new_function,
-                       new_list, new_vector, new_hash_map, Env, types_ns)
-from reader import (read_str, Blank)
+import mal_types as types
+import reader, printer
 
 # read
 def READ(str):
-    return read_str(str)
+    return reader.read_str(str)
 
 # eval
 def EVAL(ast, env):
-    #print("EVAL %s" % ast)
-    return ast
+        #print("EVAL %s" % ast)
+        return ast
 
 def PRINT(exp):
-    return pr_str(exp)
+    return printer._pr_str(exp)
 
 # repl
 def REP(str):
@@ -27,6 +25,6 @@ while True:
         if line == None: break
         if line == "": continue
         print(REP(line))
-    except Blank: continue
+    except reader.Blank: continue
     except Exception as e:
         print "".join(traceback.format_exception(*sys.exc_info()))