remove global dependence and depends functions

theano/gof/sched.py

@@ -10,32 +10,19 @@ def memodict(f):
     return memodict().__getitem__
 ## end of http://code.activestate.com/recipes/578231/ }}}
 
-@memodict
-def depends((a, b)):
+def make_depends():
+    @memodict
+    def depends((a, b)):
         """ Returns True if a depends on b """
         return (any(bout in a.inputs for bout in b.outputs)
                  or any(depends((ainp.owner, b)) for ainp in a.inputs
                                                   if ainp.owner))
-
-def dependence(a, b):
-    """ A cmp function for nodes in a graph - does a depend on b?
-
-    Returns positive number if a depends on b
-    Returns negative number if b depends on a
-    Returns 0 otherwise
-    """
-    if depends((a, b)): return  1
-    if depends((b, a)): return -1
-    return 0
+    return depends
 
 def make_dependence_cmp():
     """ Create a comparator to represent the dependence of nodes in a graph """
-    @memodict
-    def depends((a, b)):
-        """ Returns True if a depends on b """
-        return (any(bout in a.inputs for bout in b.outputs)
-                 or any(depends((ainp.owner, b)) for ainp in a.inputs
-                                                  if ainp.owner))
+
+    depends = make_depends()
 
     def dependence(a, b):
         """ A cmp function for nodes in a graph - does a depend on b?

theano/gof/tests/test_sched.py

-from theano.gof.sched import (dependence, sort_apply_nodes, reverse_dict,
-        _toposort, posort)
+from theano.gof.sched import (make_dependence_cmp, sort_apply_nodes,
+        reverse_dict, _toposort, posort)
 
 import theano
 from theano import tensor
 from theano.gof.graph import io_toposort
 
 def test_dependence():
+    dependence = make_dependence_cmp()
+
     x = tensor.matrix('x')
     y = tensor.dot(x*2, x+1)
     nodes = io_toposort([x], [y])