[Q] Type checking...

[Gordon McMillan]

Olivier Deckmyn asks:
> 
> Abstract : [Q]How to check the type of an instance before(after?)
> sending it to a method...

The builtin function "isinstance".

If class A has method frobnicate(), your code will be much more 
general if you do
 class B:
   def DoSomething(self, thing):
     try:
       thing.frobnicate()
     except:
       ...

This lets your users implement the A interface without having to 
actually be an A.


- Gordon