[Scheme-reports] Mutable Pairs

[Anton van Straaten]

Somebody, probably Brian, apparently wrote:
>> Take data abstraction.  Scheme lets you define abstract data types.
>> It also lets you not define abstract data types.  The students who
>> learn to do the former spend less time debugging.  This is a
>> learning experience.  If Scheme forced you to define abstract data
>> types, programs would arguably be safer, but students would learn
>> less.

Unless Scheme is only intended to be a teaching language, it doesn't 
seem necessary to have training features as a permanent feature of the 
language, particularly when it has a pervasive effect on the language 
semantics, as is the case with mutable pairs.

The PLT/Racket teaching dialect approach seems relevant here.

Anton