type system in erlang?

[Kostis Sagonas]

Bob Smart replied to my question: 

 > > The basic problem with type systems is that there is no single one
 > > that will satisfy all wishes.  What sort of type system would you
 > > want to see?
 > 
 > The sensible definition of the type of a value is "everything the
 > compiler knows about a value at the time the compilation is done".

I do not get how this answers my question...  This basically equates
the ideal type system with whatever type analysis the compiler performs
at some given point.  So the current type system of the BEAM compiler,
which keeps no type information about values (other than "it's an
Erlang term"), is a satisfactory one.  Probably not what you had in
mind.

I can of course see that you probably wanted to write "could know"
rather than "knows" in your answer, but it is precisely this
information that I am after (and this is the reason why I wrote the
statement before the question).

Cheers,
Kostis