[Haskell] Re: ST/STRef vs. IO/IORef

[Till Mossakowski]

Remi Turk wrote:

> In a final attempt to convince someone of I'm not exactly sure
> what, I attached a simple implementation of the ST monad in terms
> of unsafePerformIO + IORef + IOArray.

OK, but you have to reason about this implementation to show that
it is safe (which may be difficult because unsafePerformIO makes
reasoning extremely difficult), while the primitives of ST are
more easily proved to be safe.

-- 
Till Mossakowski               Phone +49-421-218-4683
Dept. of Computer Science      Fax +49-421-218-3054
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