Convert python literals to theano constants before handing them off to Subtensor.

theano/tensor/var.py

@@ -4,7 +4,8 @@ import numpy
 
 import theano
 from theano.compat import all, PY3
-from theano.scalar import ComplexError, IntegerDivisionError
+from theano.scalar import (ComplexError, IntegerDivisionError,
+                           ScalarConstant, int64)
 from theano.gof import Constant, Variable
 from theano.gof.utils import hashtype
 from theano.tensor.utils import hash_from_ndarray
@@ -348,6 +349,19 @@ class _tensor_py_operators:
     def __getitem__(self, args):
         if not isinstance(args, tuple):
             args = args,
+        # Convert python literals to theano constants
+        def conv(a):
+            if a is None:
+                return a
+            elif isinstance(a, slice):
+                return slice(conv(a.start),
+                             conv(a.stop),
+                             conv(a.step))
+            elif isinstance(a, (int, long, numpy.integer)):
+                return ScalarConstant(int64, a)
+            else:
+                return a
+        args = tuple(map(conv, args))
         # Determine if advanced indexing is needed or not
         # The logic is already in Subtensor.convert: if it succeeds,
         # standard indexing is used; if it fails with