Nat and Fin: peano naturals and finite numbers

Version on this page:0.0.1
LTS Haskell 12.22:0.0.1
Stackage Nightly 2018-12-15:0.0.1
Latest on Hackage:0.0.1

See all snapshots fin appears in

BSD3 licensed by Oleg Grenrus
Maintained by Oleg.Grenrus

Module documentation for 0.0.1

There are no documented modules for this package.

This package provides two simple types, and some tools to work with them. Also on type level as DataKinds.

-- Peano naturals
data Nat = Z | S Nat

-- Finite naturals
data Fin (n :: Nat) where
    Z :: Fin ('S n)
    S :: Fin n -> Fin ('Nat.S n)

vec implements length-indexed (sized) lists using this package for indexes.

The Data.Fin.Enum module let's work generically with enumerations.

See Hasochism: the pleasure and pain of dependently typed haskell programming by Sam Lindley and Conor McBride for answers to how and why. Read APLicative Programming with Naperian Functors by Jeremy Gibbons for (not so) different ones.

Similar packages


Revision history for boring


  • GHC-8.4.1 / base-4.11 support


  • First version. Released on an unsuspecting world.
Depends on 3 packages:
Used by 2 packages:
comments powered byDisqus