User:Zzo38/Proposal for additional kinds
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(Difference between revisions)
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==New kinds== | ==New kinds== | ||
## -- New name for (#) kind (although (#) is available for compatibility) | ## -- New name for (#) kind (although (#) is available for compatibility) | ||
| - | + | & -- Kind for classes | |
+ -- Kind for type-level natural numbers | + -- Kind for type-level natural numbers | ||
$ -- Means make up a kind from a Template Haskell code | $ -- Means make up a kind from a Template Haskell code | ||
| Line 9: | Line 9: | ||
==Kind of classes== | ==Kind of classes== | ||
Example: | Example: | ||
| - | + | * -> & -- Kind of Eq class. | |
| - | + | (* -> *) -> & -- Kind of Monad class. | |
| - | * -> | + | (* -> &) -> & -- Class of classes. |
| - | + | + -> * -> & -- Infinite series of classes, selected by a natural number. | |
| - | + -> | + | |
| - | + | ||
| - | + | ||
==Natural number kind== | ==Natural number kind== | ||
Revision as of 01:48, 5 September 2011
This document is proposal about additional kinds.
1 New kinds
## -- New name for (#) kind (although (#) is available for compatibility) & -- Kind for classes + -- Kind for type-level natural numbers $ -- Means make up a kind from a Template Haskell code
2 Kind of classes
Example:
* -> & -- Kind of Eq class. (* -> *) -> & -- Kind of Monad class. (* -> &) -> & -- Class of classes. + -> * -> & -- Infinite series of classes, selected by a natural number.
3 Natural number kind
If a type requires a parameter, it can be a + kind, meaning numbers.
There should be some way to specify a type taking natural numbers by defining it for zero and them for a successor, so that it applies for all natural numbers.
It also means a type of kind + -> + -> + can be a type of adding numbers or other stuff like that, too.
