added scalar upcasting to ScalarMixedOp

scalar.py

@@ -176,6 +176,7 @@ class Scalar(ResultBase):
 
 
 class ScalarMixedOp(GuardedOp):
+    """Olivier: document this stuff! -JB"""
 
     nin = -1
     nout = 1
@@ -185,7 +186,8 @@ class ScalarMixedOp(GuardedOp):
             if len(inputs) != self.nin:
                 raise TypeError("Wrong number of inputs for %s (got %i, expected %i)" \
                                     % (self.__class__.__name__, len(inputs), self.nin))
-
+        
+        inputs = [as_scalar(input) for input in inputs]
         i_dtypes = [getattr(input, 'dtype', None) for input in inputs]
         o_dtypes = utils.from_return_values(self.propagate_dtypes(*i_dtypes))