29 Jun
2015
29 Jun
'15
11:44 a.m.
On Jun 28, 2015, at 7:11 PM, Kosyrev Serge <_deepfire@feelingofgreen.ru> wrote:
Sadly, even this doesn't fly, because:
The first argument of a tuple should have kind '*', but 'a' has kind 'CatName'.
..which doesn't really change even if I replace the tuple with a product type within the CatEntry itself.
Basically GHC refuses to constrain the kind of constructor argument types beyond the granularity provided by '*'.
And so I wonder if this is one restriction among those that you aim to remove.. : -)
No -- this restriction leads to the best definition for tuples, in my opinion. Instead, you probably want a promoted tuple: put a ' before the open-parenthesis, and see if that works for you. Richard