> >  I suppose the following problem concerns "weak" types, but i don't see
> >  the reason (I have no assignment at all in this definitions !)
> 
> This is an excerpt from the ``expert'' part of the Caml FAQ
> 
> that explains the problem, its solution in Caml, and why it is considered a
> good solution.

yes, but it doesn't say much on the history of the problem. The Paulson
book does, but doesn't mention Caml. What I wonder is when Caml
adopted value polymorphism, what system was used before that and whether
the INRIA researchers did seek for (perhaps alternative) solutions
themselves. In the Standard ML community, the standard reference to this
problem is a paper of Andrew Wright (1995)... 

Simon

----------------------- Simon Helsen ------------------------ 
--       Wilhelm-Schickard-Institut fuer Informatik        --
--           Arbeitsbereich Programmierung (PU)            --
--            Universitaet Tuebingen, Germany              --
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