Merge pull request #1142 from nouiz/err_msg3

theano/compile/sharedvalue.py

@@ -182,6 +182,8 @@ def shared(value, name=None, strict=False, allow_downcast=None, **kwargs):
     """
 
     try:
+        if isinstance(value, Variable):
+            raise TypeError(" Shared variable constructor needs numeric values and not symbolic variables.")
 
         for ctor in reversed(shared.constructors):
             try:

theano/compile/tests/test_shared.py

 import numpy
 import unittest
+
 import theano
 from theano.tensor import Tensor, TensorType
-
 from theano.compile.sharedvalue import *
 
 
@@ -305,3 +305,7 @@ class Test_SharedVariable(unittest.TestCase):
 
         b = shared(numpy.zeros((5, 5), dtype='float32'))
         self.assertRaises(TypeError, f, b, numpy.random.rand(5, 5))
+
+    def test_err_symbolic_variable(self):
+        self.assertRaises(TypeError, shared, theano.tensor.ones((2, 3)))
+        shared(numpy.ones((2, 4)))