alastair at reid-consulting-uk.ltd.uk
Tue Sep 10 12:16:07 EDT 2002
> Another conflict between the FFI spec and the current library
> implementation: the spec says
> "The function bitSize returns 0 for types that don't have a
> fixed bitsize (e.g. Integer)."
> whereas the current ghc implementation defines bitSize of Integer as
> a runtime error.
I think both are unfortunate - we should just admit that not every
type has a bitsize and return a Maybe. But that doesn't seem likely
It isn't clear which is the lesser of the two evils:
- returning 0 is easy to catch but equally easy to carelessly forget
- raising an exception is harder to catch but has the huge advantage
that the failure is close to the broken code.
(Does NHC support non-deterministic exceptions? Dead easy to add if
Hugs is silent on the issue because we never implemented Bits Integer.
I think I prefer the GHC semantics.
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