stable name.
-[Alastair Reid is to blame for this!]
-
-These days, (Glasgow) Haskell seems to have a bit of everything from
-other languages: strict operations, mutable variables, sequencing,
-pointers, etc. About the only thing left is LISP's ability to test
-for pointer equality. So, let's add it in!
-
-\begin{verbatim}
-reallyUnsafePtrEquality :: a -> a -> Int#
-\end{verbatim}
-
-which tests any two closures (of the same type) to see if they're the
-same. (Returns $0$ for @False@, $\neq 0$ for @True@ - to avoid
-difficulties of trying to box up the result.)
-
-NB This is {\em really unsafe\/} because even something as trivial as
-a garbage collection might change the answer by removing indirections.
-Still, no-one's forcing you to use it. If you're worried about little
-things like loss of referential transparency, you might like to wrap
-it all up in a monad-like thing as John O'Donnell and John Hughes did
-for non-determinism (1989 (Fraserburgh) Glasgow FP Workshop
-Proceedings?)
-
-I'm thinking of using it to speed up a critical equality test in some
-graphics stuff in a context where the possibility of saying that
-denotationally equal things aren't isn't a problem (as long as it
-doesn't happen too often.) ADR
-
-To Will: Jim said this was already in, but I can't see it so I'm
-adding it. Up to you whether you add it. (Note that this could have
-been readily implemented using a @veryDangerousCCall@ before they were
-removed...)
-
-
-- HWL: The first 4 Int# in all par... annotations denote:
-- name, granularity info, size of result, degree of parallelism
-- Same structure as _seq_ i.e. returns Int#
projects / ghc-hetmet.git / blobdiff