Question about overloading of binary operators

[Raj Bandyopadhyay]

Hi

Here's a simple class example I've defined

#############################
class myInt(int):
    def __add__(self,other):
       return 0

print 5 + myInt(4)   #prints 9
print myInt(4) + 5   #prints 0
#############################

The Python binary operation function (binary_op1() in 
Objects/abstract.c) states
the rules for binary operations as follows:

 v w   Action
  -------------------------------------------------------------------
  new   new w.op(v,w)[*], v.op(v,w), w.op(v,w)
  new   old v.op(v,w), coerce(v,w), v.op(v,w)
  old   new w.op(v,w), coerce(v,w), v.op(v,w)
  old   old coerce(v,w), v.op(v,w)

  [*] only when v->ob_type != w->ob_type && w->ob_type is a subclass of
      v->ob_type


It seems that my example should fall in case 1, and in both cases, the 
__add__ function of the subclass should be used, returning 0, regardless 
of operand order. However, in one case the subclass's function is used 
and not in the other case. What am I missing here?

Thanks
Raj