[Haskell] Re: Global Variables and IO initializers

MR K P SCHUPKE k.schupke at imperial.ac.uk
Fri Nov 5 14:06:55 EST 2004

>Eiffel can dispense with global variables not least because objects contain
>mutable state. And the methods cann access this state inside their object
>without taking it as an argument.

All of which you can do in Haskell (including the objects) with no additional
extensions, see:


Which is a draft paper by Oleg, Ralf and myself.

We can even do pure functional objects (don't think thats in the paper
yet) of course if the object does IO it must be in the IO monad or
if it has _mutable_ state it must be in the ST monad.


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