generic-labels: Generically extract and replace collections of record fields

[ bsd3, data, generics, library, records ] [ Propose Tags ]

Handle various conversion operations between record types, such as projecting out a collection of fields from a record, or plugging in values for a subset of the fields of a larger record.

Works both with built-in Haskell records, as well as explicitly labelled types ( #label := value ) :: ( "label" := Type ) .

Project out a smaller record using project:

  data IBXD x = IBXD { i :: Int, b :: Bool, x :: x, d :: Double }
    deriving stock Generic
  data XI x = XI { x :: x, i :: Int }
    deriving stock Generic
  ibxd_to_xi :: IBXD x -> XI x
  ibxd_to_xi = project

Plug in a subset of fields using inject:

  xi_into_ibxd :: XI x -> IBXD x -> IBXD x
  xi_into_ibxd = inject

Create a record out of two collections of arguments using adapt:

  xi_plus_bd_makes_ibxd :: XI x -> ( "b" := Bool, "d" := Double ) -> IBXD x
  xi_plus_bd_makes_ibxd = adapt

See also the library's readme.


Note: This package has metadata revisions in the cabal description newer than included in the tarball. To unpack the package including the revisions, use 'cabal get'.

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Dependencies base (>=4.14 && <4.17), generic-lens-core (>=2.0 && <2.2) [details]
License BSD-3-Clause
Author Sam Derbyshire
Maintainer Sam Derbyshire
Revised Revision 1 made by sheaf at 2021-02-09T11:28:09Z
Category Data, Generics, Records
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Source repo head: git clone git://
Uploaded by sheaf at 2021-02-09T10:42:17Z
Downloads 184 total (5 in the last 30 days)
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Status Docs available [build log]
Last success reported on 2021-02-09 [all 1 reports]