| > Another possiblity would be to make the ConCls class look like this
| > class ConCls c where
| > name :: String
| > arity :: Int
| > ...etc...
| >
| > Now we'd have to give an explicit type argument at the call site:
| >
| > show {| Constr c t |} (Con x) = (name {| c |}) ++ show x
| >
| > I quite like the thought of being able to supply explicit type
| > arguments.... but I don't konw how to speak about the order of type
| > parameters. What order does map takes its two type parameters in?
|
| Sorry, this seems like a non-sequitur to me?
|
| 'map' has type '(a->b) -> [a] -> [b]'; supplying explicit
| type parameters would mean giving values to 'a' and 'b'. If
| I wanted to propose notation for this, I would suggest, e.g.,
| (map :: (String -> Int) -> [String] -> [Int]) length
| ["Hello", "World"]
|
| 'name' (above) has type 'String'; the '{| c |}' is not
| providing a type parameter in the same sense.
Yes it is. 'name' would have type
forall c. ConCls c => String
It requires a type argument, just like map.
Simon
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