Isaac _______________________________________________ Haskell-prime mailing list Haskell-prime@haskell.org http://www.haskell.org/mailman/listinfo/haskell-prime
Haskell98's monomorphism restriction is too confusing! See my mistaken
GHC bug report <http://hackage.haskell.org/trac/ghc/ticket/1503>.
Whether a binding is monomorphic depends not just on syntax, but on the
amount of type constraints on the right-hand side of a binding - and I
didn't realize, because this issue usually doesn't come up (usually
types are already monomorphic or are at least typeclass qualified, or at
least don't have to be monomorphic to prevent a type error). Although
this finally convinces me that we should dump H98 m-r in favor of the
very straightforward "monomorphic pattern bindings", if we don't, at
least I believe that Report Section 4.5.5, Rule 1 needs a reword. It
uses "(un) restricted" to mean "restricted (to be monomorphic) IN SOME
CASES". Maybe a word like "suspicious" would be less misleading than
"restricted" there?
