From: Tim Vieira <tim.f.vieira@gmail.com>
Date: Wed, 31 Jul 2013 13:30:21 +0000 (-0400)
Subject: Interning is back! However, charts are never deleted.
X-Git-Url: https://hydra-www.ietfng.org/gitweb/?a=commitdiff_plain;h=aea53c07aac61fb04cbe5abe0519c0987a617a32;p=dyna2

Interning is back! However, charts are never deleted.

Fix dict= aggregator, didn't handle the null.
---

diff --git a/src/Dyna/Backend/Python/aggregator.py b/src/Dyna/Backend/Python/aggregator.py
index 20b0b54..b68b870 100644
--- a/src/Dyna/Backend/Python/aggregator.py
+++ b/src/Dyna/Backend/Python/aggregator.py
@@ -43,6 +43,8 @@ class BAggregator(Counter, Aggregator):
         self[val] -= 1
     def fromkeys(self, *_):
         assert False, "This method should never be called."
+    def empty(self):
+        return not any(m > 0 for m in self.itervalues())
 
 
 class ColonEquals(BAggregator):
@@ -91,8 +93,9 @@ class DictEquals(BAggregator):
         self[val, vs] -= 1
 
     def fold(self):
-        from stdlib import todyna
-        return todyna([b + (('$val', v),) for (v, b), cnt in self.iteritems() if cnt > 0])
+        if not self.empty():
+            from stdlib import todyna
+            return todyna([b + (('$val', v),) for (v, b), cnt in self.iteritems() if cnt > 0])
 
 
 class majority_equals(BAggregator):
diff --git a/src/Dyna/Backend/Python/interpreter.py b/src/Dyna/Backend/Python/interpreter.py
index 211636a..5208920 100644
--- a/src/Dyna/Backend/Python/interpreter.py
+++ b/src/Dyna/Backend/Python/interpreter.py
@@ -583,16 +583,25 @@ class Interpreter(object):
 
         self.recompute_coarse()
 
+        self._agenda()
+
         # if there are no more rules defining a functor; clear some of the state
         if not self.rule_by_head[rule.head_fn]:
             if rule.head_fn in self.chart:
-                del self.chart[rule.head_fn]      # delete the chart.
+                # clear aggregators
+                chart = self.chart[rule.head_fn]
+                chart.agg_name = None
+                for item in chart.intern.values():
+                    item.aggregator = None
+                # make sure chart is cleared out
+                for item in chart.intern.values():
+                    assert item.value is None
+                    assert item not in self.error
             if rule.head_fn in self.agg_name:
                 del self.agg_name[rule.head_fn]
             if rule.head_fn in self.pstate[2]:
                 del self.pstate[2][rule.head_fn]  # remove fn aggr def from parser state
 
-        self._agenda()
         return self.changed
 
     def recompute_gbc_memo(self, fn, visited=None):
diff --git a/src/Dyna/Backend/Python/term.py b/src/Dyna/Backend/Python/term.py
index b31d7f3..c158cff 100644
--- a/src/Dyna/Backend/Python/term.py
+++ b/src/Dyna/Backend/Python/term.py
@@ -14,13 +14,7 @@ class Term(object):
         self.aggregator = None
 
     def __eq__(self, other):
-        try:
-            return (self.fn, self.args) == (other.fn, other.args)
-        except AttributeError:
-            return False
-
-    def __hash__(self):
-        return hash((self.fn, self.args))
+        return self is other
 
     def __cmp__(self, other):
         try:
@@ -36,7 +30,18 @@ class Term(object):
         return '%s(%s)' % (fn, ','.join(map(_repr, self.args)))
 
 
-class Cons(Term):
+class NoIntern(Term):
+    "Mix-in which adds hash and equality method for terms which aren't interned."
+    def __eq__(self, other):
+        try:
+            return (self.fn, self.args) == (other.fn, other.args)
+        except AttributeError:
+            return False
+    def __hash__(self):
+        return hash((self.fn, self.args))
+
+
+class Cons(NoIntern, Term):
 
     def __init__(self, head, tail):
         if not (isinstance(tail, Cons) or tail is Nil):
@@ -50,12 +55,6 @@ class Cons(Term):
     def __repr__(self):
         return '[%s]' % (', '.join(map(_repr, self.aslist)))
 
-#    def __contains__(self, x):
-#        if x in self.aslist:
-#            return true
-#        else:
-#            return false
-
     def like_chart(self):
         for a in self.aslist:
             if not isinstance(a, Term):
@@ -66,23 +65,8 @@ class Cons(Term):
     def __iter__(self):
         return iter(self.aslist)
 
-#    def __eq__(self, other):
-#        try:
-#            return self.aslist == other.aslist
-#        except AttributeError:
-#            return False
 
-#    def __hash__(self):
-#        return hash(tuple(self.aslist))
-
-#    def __cmp__(self, other):
-#        try:
-#            return cmp(self.aslist, other.aslist)
-#        except AttributeError:
-#            return
-
-
-class Error(Term):
+class Error(NoIntern, Term):
     def __init__(self):
         Term.__init__(self, '$error/0', ())
 
@@ -106,23 +90,11 @@ class _Nil(Term):
     def __iter__(self):
         return iter([])
 
-#    def __eq__(self, other):
-#        try:
-#            return self.aslist == other.aslist
-#        except AttributeError:
-#            return False
-
-#    def __cmp__(self, other):
-#        try:
-#            return cmp(self.aslist, other.aslist)
-#        except AttributeError:
-#            return 1
-
 
 Nil = _Nil()
 
 
-class MapsTo(Term):
+class MapsTo(NoIntern, Term):
     def __init__(self, k, v):
         super(MapsTo, self).__init__('->/2', (k, v))
     def __repr__(self):