generic-data: Utilities for GHC.Generics

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This package provides common functions on generic types. See README.

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Dependencies base (>=4.9 && <5), contravariant, show-combinators [details]
License MIT
Copyright 2018 Li-yao Xia
Author Li-yao Xia
Category Other
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Source repo head: git clone
Uploaded by lyxia at Sun May 27 20:56:06 UTC 2018
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Status Docs available [build log]
Last success reported on 2018-05-27 [all 1 reports]
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For package maintainers and hackage trustees

Readme for generic-data-

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Generic data types in Haskell Build Status

Utilities for GHC.Generics.

Generic deriving for standard classes

Supported classes that GHC currently can't derive: Semigroup, Monoid, Applicative, Alternative, Eq1, Ord1, Show1.

Other classes from base are also supported, even though GHC can already derive them:

  • Eq, Ord, Enum, Bounded, Show (standard);
  • Functor, Foldable, Traversable (via extensions, DeriveFunctor, etc.).

To derive type classes defined elsewhere, it might be worth taking a look at one-liner.

Type metadata

Extract type names, constructor names, number and arities of constructors, etc..

Related links

generic-data aims to subsume the following packages, which may still be useful for old versions of GHC and base not supported by generic-data.

  • semigroups: generic Semigroup, Monoid.
  • transformers-compat: generic Eq1, Ord1, Show1, Read1.
  • generic-deriving: doesn't derive the classes in base (defines clones of these classes as a toy example); has Template Haskell code to derive Generic.

Here are other relevant links.

  • deriving-compat: deriving with Template Haskell.
  • one-liner: another approach to using GHC.Generics to derive instances of many type classes, including but not restricted to the above classes (this is done in one-liner-instances).
  • singletons: generic-data borrows code from this package to implement defunctionalization.

All contributions are welcome. Open an issue or a pull request on Github!