27 Sep
2008
27 Sep
'08
2:43 p.m.
Bulat Ziganshin wrote:
Hello Andrew,
Saturday, September 27, 2008, 9:23:47 PM, you wrote:
Can anybody actually demonstrate concretely how FDs and/or ATs would solve this problem? (I.e., enable you to write a class that any container can be a member of, despite constraints on the element types.)
you may find comprehensive explanation in ghc user manual, it's chapter about FDs use this as motivating example :)
Section 8.6.2, "Functional Dependencies": "There should be more documentation, but there isn't (yet). Yell if you need it." Yeah, that's real helpful. :-P But hey, there's an academic paper... *sigh* Ooo, wait a sec, section 8.6.2.2. That helps... Mmm, OK. Now can somebody explain the "FDs cause problems" part?