parametric-functor: A known-parametric Functor typeclass

[ apache, data, library ] [ Propose Tags ]

As Oleg Grenrus argued in 2019, Functors should be parametric, and in particular should:

  • Satisfy fmap coerce = coerce

  • Have a ∀ a b. Coercible a b ⇒ Coercible (f a) (f b) super-constraint

Until this change gets adopted in base, this package can be used for a variant of Functor which satisfies these requirements.


Maintainer's Corner

Package maintainers

For package maintainers and hackage trustees


  • No Candidates
Versions [RSS],
Change log
Dependencies base (>=4.12 && <5), transformers (>=0.2 && <1.0) [details]
License Apache-2.0
Copyright Copyright 2024 Shea Levy Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
Author Shea Levy
Category Data
Home page
Bug tracker
Source repo head: git clone
Uploaded by shlevy at 2024-01-15T14:51:35Z
Distributions NixOS:
Reverse Dependencies 2 direct, 0 indirect [details]
Downloads 75 total (5 in the last 30 days)
Rating (no votes yet) [estimated by Bayesian average]
Your Rating
  • λ
  • λ
  • λ
Status Docs available [build log]
Last success reported on 2024-01-15 [all 1 reports]