new Smalltalk programmer's thoughts

Wolfgang Helbig helbig at Lehre.BA-Stuttgart.DE
Sat May 6 07:21:23 UTC 2006

Hi Stef,
you thought:
>...that we should change if this is important.
>So Smalltalk should not be a prison or a dusty museum

It shouldn't and it isn't.

But the changes I'd need in this case are reaching too far. They'd include:
- Upper bounds of integer intervals are exclusive and lower bounds inclusive
- Index ranges start at zero
- The positions of Positionable Streams would take the same values as
  the indexed variables of their underlying collections.

With theses changes predicates involving indexes and positions get more elegant.
This in turn lessens the burden you face when formulating specifications of 
methods and reasoning about methods to prove that they meet the specification.

This in turn is the only technique I know of that saves you from "off by one"
errors in particular and "bugs" in general.

So the changes *are* important.

And hard to implement in Smalltalk.

Or, viewed as biological species, Squeak and even Smalltalk-80 evolved to a 
level where they lost the flexibility to meet the "new" challenge of switching 
from the dark art of medieval metaphors to the scientific technique of logical 

By the way, at
I posted another "challenge". It is quite harmless. :-)


Weniger, aber besser.

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