While waiting for the gurus to bestow upon me fragments of their wisdom, I've stumbled further on my path to enligthenment: ketil@ii.uib.no (Ketil Z. Malde) writes:
E.g. how much [space] for [...] a data type with only nullary data constructors -- should I use Word8s instead?
From my superficial testing
data Alphabet = A | B | C | D is no worse than using Word8. Is this a correct observation? Would it change if I somehow managed to get things to work with Word8# instead, or will the compiler automatically unbox things when I stuff them in tuples, lists or arrays anyway? The GHC docs seem to discourage using unboxed types. (BTW, it took me a while to discover that Word8 hides in PrelWord. I may have missed some obvious place to look, but perhaps it could be better documented?)
I realize I can use profiling to determine heap use,
Actually, I can't. Binaries created with ghc -prof -auto-all segmentation fault on startup. This is GHC 5.02.1 installed from an RPM on a RH7.2 box. -kzm -- If I haven't seen further, it is by standing in the footprints of giants