Added try statement to switch sink optimizations not to raise constant checking errors

theano/tensor/opt.py

@@ -1194,16 +1194,22 @@ def local_mul_switch_sink(node):
     for idx , i in enumerate(node.inputs):
         if i.owner and i.owner.op == T.switch:
             switch = i.owner
-            if get_constant_value(switch.inputs[1]) == 0.:
-                listmul = node.inputs[:idx] + node.inputs[idx+1:]
-                fct = [T.switch(switch.inputs[0],0,T.mul(*(listmul + [switch.inputs[2]])))]
-                fct[0].values_eq_approx = fct[0].type.values_eq_approx_remove_nan
-                return fct
-            if get_constant_value(switch.inputs[2]) == 0.:
-                listmul = node.inputs[:idx] + node.inputs[idx+1:]
-                fct = [T.switch(switch.inputs[0],T.mul(*(listmul + [switch.inputs[1]])),0)]
-                fct[0].values_eq_approx = fct[0].type.values_eq_approx_remove_nan
-                return fct
+            try:
+                if get_constant_value(switch.inputs[1]) == 0.:
+                    listmul = node.inputs[:idx] + node.inputs[idx+1:]
+                    fct = [T.switch(switch.inputs[0],0,T.mul(*(listmul + [switch.inputs[2]])))]
+                    fct[0].values_eq_approx = fct[0].type.values_eq_approx_remove_nan
+                    return fct
+            except TypeError:
+               pass 
+            try:
+                if get_constant_value(switch.inputs[2]) == 0.:
+                    listmul = node.inputs[:idx] + node.inputs[idx+1:]
+                    fct = [T.switch(switch.inputs[0],T.mul(*(listmul + [switch.inputs[1]])),0)]
+                    fct[0].values_eq_approx = fct[0].type.values_eq_approx_remove_nan
+                    return fct
+            except TypeError:
+                pass
     return False
 
 @register_canonicalize
@@ -1224,14 +1230,20 @@ def local_div_switch_sink(node):
     op = node.op
     if node.inputs[0].owner and node.inputs[0].owner.op == T.switch:
         switch = node.inputs[0].owner
-        if get_constant_value(switch.inputs[1]) == 0.:
-            fct = [T.switch(switch.inputs[0],0,op(switch.inputs[2],node.inputs[1]))]
-            fct[0].values_eq_approx = fct[0].type.values_eq_approx_remove_nan
-            return fct
-        if get_constant_value(switch.inputs[2]) == 0.:
-            fct = [T.switch(switch.inputs[0],op(switch.inputs[1],node.inputs[1]),0)]
-            fct[0].values_eq_approx = fct[0].type.values_eq_approx_remove_nan
-            return fct
+        try:
+            if get_constant_value(switch.inputs[1]) == 0.:
+                fct = [T.switch(switch.inputs[0],0,op(switch.inputs[2],node.inputs[1]))]
+                fct[0].values_eq_approx = fct[0].type.values_eq_approx_remove_nan
+                return fct
+        except TypeError:
+            pass
+        try:
+            if get_constant_value(switch.inputs[2]) == 0.:
+                fct = [T.switch(switch.inputs[0],op(switch.inputs[1],node.inputs[1]),0)]
+                fct[0].values_eq_approx = fct[0].type.values_eq_approx_remove_nan
+                return fct
+        except TypeError:
+            pass
     return False