To make it referentially transparent you might want to consider adding 'por', parallel or, instead. It's like (||), but symmetric in its treatment of bottom. -- Lennart On Sep 10, 2006, at 00:21 , Ashley Yakeley wrote:
Is it possible to write nondet?
nondet :: a -> a -> a
nondet _|_ _|_ = _|_ nondet _|_ q = q nondet p _|_ = p nondet p q = p or q
nondet evaluates its arguments in parallel, and returns the first one of them to evaluate. It's thus a bit different from the "par" of GPH. This isn't referentially transparent, of course, but maybe it could be written in the IO monad:
nondet p q = unsafePerformIO (getnondet p q)
getnondet :: a -> a -> IO a
-- Ashley Yakeley, Seattle WA
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