[Haskell-cafe] Haskell for non-mathematicians (was: Specify array or list size?)

[karczma at info.unicaen.fr]

Bulat Ziganshin discusses with SS: 

> SS> Types is a very important concept and I think that should be
> SS> emphasized in the first lecture. If one goes through types _and_
> SS> values from the very beginning a strongly typed language will be of
> SS> the same aid to beginners as it is to experts. 
> 
> imvho, exposing types to non-professionals is like exposing light
> theory to a kid which just want to draw a picture. values are just
> enough to these peoples

No, I am sorry, I disagree rather strongly. I taught programming to
fresh undergraduates, and a little bit, occasionally to secondary school
folk. We used Scheme. I taught also some programming to biology students,
using Python. (Biology students are very resistant to all kind of mathe-
matical reasoning...)
So, as you see, we used dynamically typed languages. 

First bugs the students/pupils see, after having mastered the syntax are
type errors. Presented as such. "sin expects a float". or " ... of type
<number>". Hiding the typing at this level is a crime, it prevents them
from understanding what is the essence of their bugs.
I was OBLIGED to discuss types quite early, and everybody was satisfied.
I am afraid that your claim is not based on experience. 


Jerzy Karczmarczuk