Jonathan Cast wrote:
It's weird. ML-derived languages are functional languages at the value level (and have regular lambda-bound variables in consequence), but are logical languages at the type level (and have logical variables in consequence). So ordinary lambda-bound variables, like in ML-style functors (parametrized modules) act more like type constants than like type variables.
Thanks - the above seems to be a promising avenue of thought to arrive at clarity regarding case distinctions at the type level, and I can see here the basis for a good argument of why there would actually be no inconsistency regarding the use of capitals for module type members and lowercase for the class parameters. Perhaps this is also the root of the difference between associated type synonyms and class params.
Ie at the type level, uppercase == functional variable (aka "constant") and lowercase == logic variable...
The type level now seems to me to be quite significantly more complicated than the value level due to the mixing of functional and logic programming, not to mention that at the type level "variables" in an outer scope become "constants" in an inner scope as far as pattern matching is concerned whereas for value patterns variables are always fresh and never scoped (over other patterns).
Therefore I've decided to deal with the issue of case at each level separately since it seems immediately clear that the case distinction at the value level, as in Haskell/OCaml/Moby, is obviously good due to the "foolproof" nature of value patterns you pointed out, whereas at the type level it may also be good but I'll need a few more months to think about it... ;-)
Cheers, Brian. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
