small refactoring.

theano/tensor/basic.py

@@ -373,6 +373,11 @@ def get_constant_value(v):
         if isinstance(v.owner.op, Subtensor) and v.ndim==0:
             if isinstance(v.owner.inputs[0], TensorConstant):
                 return v.owner.inputs[0].data[v.owner.op.idx_list[0]]
+
+            # The index list 'idx_list' should have length one
+            # since joining scalar variables results in a 1D vector.
+            assert len(v.owner.op.idx_list) == 1
+
             #Needed to make better graph in this test.
             #theano/tensor/tests/test_sharedvar.py:test_shared_options.test_specify_shape_partial
             if (v.owner.inputs[0].owner and
@@ -382,9 +387,6 @@ def get_constant_value(v):
                 # used in the sub-tensor).
                 all(var.ndim==0 for var in v.owner.inputs[0].owner.inputs)):
 
-                # The index list 'idx_list' should have length one
-                # since joining scalar variables results in a 1D vector.
-                assert len(v.owner.op.idx_list) == 1
                 # Note the '+ 1' is because the first argument to Join is the
                 # axis.
                 ret = v.owner.inputs[0].owner.inputs[v.owner.op.idx_list[0]+1]
@@ -398,9 +400,6 @@ def get_constant_value(v):
                 # We put this check in case there is change in the future
                 all(var.ndim==0 for var in v.owner.inputs[0].owner.inputs)):
 
-                # The index list 'idx_list' should have length one
-                # since joining scalar variables results in a 1D vector.
-                assert len(v.owner.op.idx_list) == 1
                 ret = v.owner.inputs[0].owner.inputs[v.owner.op.idx_list[0]]
                 ret = get_constant_value(ret)
                 #MakeVector can cast implicitly its input in some case.