[Tutor] Re: Python information

[alan.gauld@bt.com]

> COBOL programmers? Never did get it. But that's another story. :-)

:-)

But they're all using COBOL PLUS OVBJECTS now I guess!

> My experience is that most people who have trouble with 
> objects do so because they try to make them much more 
> complicated than they really are.

Actually I find a different prolem arises. Experienced 
programmers tend to try to relate objects to their 
prior knowledge. Thus they think an object is a C struct 
with fields which are function pointers. Then they think 
about messaging as simply a function call. Then they 
think of inheritance as a code reuse mechanism. And 
finally they think of class heirarchies as abstract 
data types.

All of the above analogies are accurate to at least 
some level. But all of them are fundamentally misleading 
when trying to think in terms of objects as a 
fundamental unit of code in their own right.

Its one reason that I have come to the conclusion that 
teaching a C programmer OOP using C++ or Java is a 
mistake - its better to teach something radically 
different in syntax terms like Smalltalk or Lisp 
(or more arguably Python). Then the tendency to 
relate to previous knowledge is reduced. Smalltalk 
is particularly effective because even the way you 
write the code is different (in a class browser rather 
than a file editor)

Alan g.
Author of the 'Learning to Program' web site
http://www.freenetpages.co.uk/hp/alan.gauld

PS
The curious can look/learn about smalltalk at the 
ObjectArts web site( http://www.object-arts.com/ ), 
home of the excellent Dolphin smalltalk or alternativel 
try the Squeak project at http://www.squeak.org...