# User:Zzo38/Proposal for additional kinds

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< User:Zzo38(Difference between revisions)

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It also means a type of kind <tt>+ -> + -> +</tt> can be a type of adding numbers or other stuff like that, too. | It also means a type of kind <tt>+ -> + -> +</tt> can be a type of adding numbers or other stuff like that, too. | ||

+ | |||

+ | ==See also== | ||

+ | * [http://hackage.haskell.org/trac/ghc/wiki/KindFact KindFact] | ||

[[Category:Proposals]] | [[Category:Proposals]] |

## Revision as of 01:50, 5 September 2011

This document is proposal about additional kinds.

## Contents |

## 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.