Use Callable abc where appropriate.

theano/compat/__init__.py

@@ -5,6 +5,7 @@
 from theano.compat.six import PY3, b, BytesIO, next
 from theano.compat.six.moves import configparser
 from theano.compat.six.moves import reload_module as reload
+import collections
 
 __all__ = ['PY3', 'b', 'BytesIO', 'next', 'configparser', 'reload']
 
@@ -77,7 +78,7 @@ __all__ += ['cmp', 'operator_div', 'partial', 'defaultdict', 'deque',
 class DefaultOrderedDict(OrderedDict):
     def __init__(self, default_factory=None, *a, **kw):
         if (default_factory is not None and
-                not callable(default_factory)):
+                not isinstance(default_factory, collections.Callable)):
             raise TypeError('first argument must be callable')
         OrderedDict.__init__(self, *a, **kw)
         self.default_factory = default_factory

theano/compile/ops.py

@@ -13,6 +13,7 @@ from theano.compat.six.moves import xrange
 
 
 import numpy
+import collections
 
 
 def register_view_op_c_code(type, code, version=()):
@@ -569,7 +570,7 @@ def as_op(itypes, otypes, infer_shape=None):
     itypes = list(itypes)
     otypes = list(otypes)
 
-    if infer_shape is not None and not callable(infer_shape):
+    if infer_shape is not None and not isinstance(infer_shape, collections.Callable):
         raise TypeError("infer_shape needs to be a callable")
 
     def make_op(fn):

theano/configparser.py

@@ -14,6 +14,7 @@ from theano.compat.six import StringIO
 
 import theano
 from theano.compat import configparser as ConfigParser
+import collections
 
 _logger = logging.getLogger('theano.configparser')
 
@@ -265,7 +266,7 @@ def AddConfigVar(name, doc, configparam, root=config, in_c_key=True):
         configparam.in_c_key = in_c_key
         # Trigger a read of the value from config files and env vars
         # This allow to filter wrong value from the user.
-        if not callable(configparam.default):
+        if not isinstance(configparam.default, collections.Callable):
             configparam.__get__()
         else:
             # We do not want to evaluate now the default value
@@ -309,7 +310,7 @@ class ConfigParam(object):
                     for v in self.default():
                         val_str = v
                         self.__set__(None, val_str)
-                elif callable(self.default):
+                elif isinstance(self.default, collections.Callable):
                     val_str = self.default()
                 else:
                     val_str = self.default
@@ -365,7 +366,7 @@ class TypedParam(ConfigParam):
 
         def filter(val):
             cast_val = mytype(val)
-            if callable(is_valid):
+            if isinstance(is_valid, collections.Callable):
                 if is_valid(cast_val):
                     return cast_val
                 else:

theano/printing.py

@@ -12,6 +12,7 @@ import warnings
 import hashlib
 
 import numpy as np
+import collections
 
 try:
     import pydot as pd
@@ -210,7 +211,7 @@ N.B.:
 def _print_fn(op, xin):
     for attr in op.attrs:
         temp = getattr(xin, attr)
-        if callable(temp):
+        if isinstance(temp, collections.Callable):
             pmsg = temp()
         else:
             pmsg = temp

theano/sandbox/symbolic_module.py

@@ -2,6 +2,7 @@ from __future__ import print_function
 import copy, inspect
 import theano
 import theano.tensor as T
+import collections
 
 #import klass
 
@@ -36,7 +37,7 @@ class InitGraph(type):
             # print '  adding class attribute', key
             if isinstance(val, theano.Variable) and val.name is None:
                 val.name = key
-            if callable(val):
+            if isinstance(val, collections.Callable):
                 setattr(cls, key, staticmethod(val))
             else:
                 setattr(cls, key, val)
@@ -317,7 +318,7 @@ if 0:
                 except Exception:
                     kres = klass.KlassVariable(val)
                 setattr(SymMod, key, kres)
-            elif callable(val) and getattr(val, '__is_symbolic'):
+            elif isinstance(val, collections.Callable) and getattr(val, '__is_symbolic'):
                 setattr(SymMod, key, val)
 
         return SymMod()

theano/scalar/basic.py

@@ -33,6 +33,7 @@ from theano.gradient import DisconnectedType
 from theano.gradient import grad_undefined
 
 from theano.printing import pprint
+import collections
 
 builtin_complex = complex
 builtin_int = int
@@ -837,7 +838,7 @@ class ScalarOp(Op):
     def __init__(self, output_types_preference=None, name=None):
         self.name = name
         if output_types_preference is not None:
-            if not callable(output_types_preference):
+            if not isinstance(output_types_preference, collections.Callable):
                 raise TypeError(
                     "Expected a callable for the 'output_types_preference' argument to %s. (got: %s)" %
                     (self.__class__, output_types_preference))