On 15 July 2005 11:24, Henning Thielemann wrote:
On Fri, 15 Jul 2005, Simon Marlow wrote:
On 15 July 2005 09:48, Henning Thielemann wrote:
The limit in Haskell is that most compilers don't conform to the Haskell 98 report which allows mutually recursive modules. But I think the compilers should allow them instead of forcing users to put many type and class definitions into one module.
I hope you weren't including GHC in "most compilers" :-) GHC's implementation of mutually recursive modules is conformant with Haskell 98 (see Section 5.7).
But there are unresolved problems with class definitions. http://www.haskell.org/pipermail/haskell-cafe/2005-May/009873.html
Is this covered by the statement "Modules may be mutually recursive."? http://www.haskell.org/onlinereport/modules.html
Ok, mututal recursion between classes in separate modules isn't currently supported (I'd forgotten about that). But it's a bit harsh to say that because of this missing feature GHC doesn't support mutually recursive modules - we've been using mutually recursive modules in GHC itself for nearly a decade! Cheers, Simon