Python from Wise Guy's Viewpoint

[Andreas Rossberg]

Pascal Costanza wrote:
> 
> Can you show me an example of a program that does't make sense anymore 
> when you strip off the static type information?

Here is a very trivial example, in SML:

	20 * 30

Multiplication, as well as literals, are overloaded. Depending on 
whether you type this expression as Int8.int (8-bit integers) or 
IntInf.int (infinite precision integer) the result is either 600 or an 
overflow exception.

So the program does not make sense without type information, because it 
does not have an unambiguous (i.e. no) semantics.

I'm ready to admit that it may be a dubious example of a typing feature. 
But it is simple, and clearly sufficient to disprove your repeated claim 
that static types don't add expressiveness to a language. If you did not 
have them for the example above, you needed some other feature to 
express the disambiguation.

	- Andreas

-- 
Andreas Rossberg, rossberg at ps.uni-sb.de

"Computer games don't affect kids; I mean if Pac Man affected us
  as kids, we would all be running around in darkened rooms, munching
  magic pills, and listening to repetitive electronic music."
  - Kristian Wilson, Nintendo Inc.