Andreas Rossberg wrote: > Pascal Costanza wrote: >> >> Consider a simple expression like 'a + b': In a dynamically typed >> language, all I need to have in mind is that the program will attempt >> to add two numbers. In a statically typed language, I additionally >> need to know that there must a guarantee that a and b will always hold >> numbers. > > I'm confused. Are you telling that you just write a+b in your programs > without trying to ensure that a and b are in fact numbers??
Basically, yes. Note that this is a simplistic example. Consider, instead, sending a message to an object, or calling a generic function, without ensuring that there will be applicable methods for all possible cases. When I get a "message not understood" exception, I can then decide whether that kind of object shouldn't be a receiver in the first place, or else whether I should define an appropriate method. I don't want to be forced to decide this upfront, because either I don't want to be bothered, or maybe I simply can't because I don't understand the domain well enough yet, or maybe I want to keep a hook to be able to update the program appropriately while it is running. Pascal -- 3rd European Lisp Workshop July 3 - Nantes, France - co-located with ECOOP 2006 http://lisp-ecoop06.bknr.net/ -- http://mail.python.org/mailman/listinfo/python-list
