fin: Nat and Fin: peano naturals and finite numbers

[ bsd3, data, dependent-types, library, singletons ] [ Propose Tags ]

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.

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Versions [faq] 0, 0.0.1, 0.0.2, 0.0.3
Change log ChangeLog.md
Dependencies base (>=4.7 && <4.13), bifunctors (>=5.5.3 && <5.6), dec (>=0.0.3 && <0.1), deepseq (>=1.3.0.2 && <1.5), hashable (>=1.2.7.0 && <1.4), nats (>=1.1.2 && <1.2), semigroups (>=0.18.4 && <0.20), void (>=0.7.2 && <0.8) [details]
License BSD-3-Clause
Copyright (c) 2017-2019 Oleg Grenrus
Author Oleg Grenrus <oleg.grenrus@iki.fi>
Maintainer Oleg.Grenrus <oleg.grenrus@iki.fi>
Category Data, Dependent Types, Singletons
Home page https://github.com/phadej/vec
Bug tracker https://github.com/phadej/vec/issues
Source repo head: git clone https://github.com/phadej/vec.git
Uploaded by phadej at Wed Jun 19 21:24:42 UTC 2019
Distributions LTSHaskell:0.0.2, NixOS:0.0.2, Stackage:0.0.2
Downloads 1114 total (113 in the last 30 days)
Rating 2.0 (votes: 1) [estimated by rule of succession]
Your Rating
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Status Hackage Matrix CI
Docs available [build log]
Last success reported on 2019-06-19 [all 1 reports]

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