From 139ab700f791ef6f4098b48a88895597e13beb9d Mon Sep 17 00:00:00 2001
From: Tim Vieira <tim.f.vieira@gmail.com>
Date: Wed, 10 Jul 2013 19:36:58 -0400
Subject: [PATCH] nonfunctional tweaks to handling of '->'.

---
 src/Dyna/Backend/Python/interpreter.py |  4 +++-
 src/Dyna/Backend/Python/stdlib.py      |  4 ++--
 src/Dyna/Backend/Python/term.py        | 10 +++++++---
 3 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/src/Dyna/Backend/Python/interpreter.py b/src/Dyna/Backend/Python/interpreter.py
index 83a2499..ea2b06e 100644
--- a/src/Dyna/Backend/Python/interpreter.py
+++ b/src/Dyna/Backend/Python/interpreter.py
@@ -78,7 +78,7 @@ from path import path
 
 import load, post
 
-from term import Term, Cons, Nil
+from term import Term, Cons, Nil, MapsTo
 from chart import Chart
 from utils import ip, red, green, blue, magenta, yellow, parse_attrs, \
     ddict, dynac, read_anf, strip_comments, _repr, hide_ugly_filename
@@ -272,6 +272,8 @@ class Interpreter(object):
             return Cons(*args)
         if fn == 'nil/0':
             return Nil
+        if fn == '->/2':
+            return MapsTo(*args)
 
         if fn == '$key/1':
             self.new_fn(fn, '=')
diff --git a/src/Dyna/Backend/Python/stdlib.py b/src/Dyna/Backend/Python/stdlib.py
index 81c62c9..8327652 100644
--- a/src/Dyna/Backend/Python/stdlib.py
+++ b/src/Dyna/Backend/Python/stdlib.py
@@ -1,5 +1,5 @@
 import re
-from term import Term, Cons, Nil
+from term import Term, Cons, Nil, MapsTo
 from collections import Counter
 from utils import pretty, pretty_print
 
@@ -77,7 +77,7 @@ def todyna(x):
         #for k,v in x.items():
         #    c = AList(todyna([k,v]), c)
         #return c
-        return todyna(x.items())
+        return todyna([MapsTo(k,v) for k,v in x.items()])
 
     elif isinstance(x, (list, tuple)):
         c = Nil
diff --git a/src/Dyna/Backend/Python/term.py b/src/Dyna/Backend/Python/term.py
index a9f032b..f8b1e39 100644
--- a/src/Dyna/Backend/Python/term.py
+++ b/src/Dyna/Backend/Python/term.py
@@ -31,9 +31,6 @@ class Term(object):
     def __repr__(self):
         "Pretty print a term. Will retrieve the complete (ground) term."
 
-        if self.fn == '->/2':
-            return '%s -> %s' % self.args
-
         fn = '/'.join(self.fn.split('/')[:-1])  # drop arity from name.
         if not self.args:
             return fn
@@ -134,3 +131,10 @@ class _Nil(Term):
 
 
 Nil = _Nil()
+
+
+class MapsTo(Term):
+    def __init__(self, k, v):
+        super(MapsTo, self).__init__('->/2', (k, v))
+    def __repr__(self):
+        return '%s -> %s' % self.args
-- 
2.50.1