BSD3 licensed by Chris Done
Maintained by chrisdone@gmail.com

Module documentation for 0.3.2

labels

Declare and access tuple fields with labels

This package is experimental, exploring the design space opened up by the implemented and to-be-implemented work on extensible records in GHC.

Note: You need GHC 8.0.1.

Basic examples

The haddock docs are here.

Enable these extensions:

  • In GHCi: :set -XOverloadedLabels -XTypeOperators -XDataKinds -XFlexibleContexts

  • In a module: {-# LANGUAGE OverloadedLabels, TypeOperators, DataKinds, FlexibleContexts #-}

Let’s use GHCi:

> import Labels
> :set -XOverloadedLabels -XTypeOperators -XDataKinds -XFlexibleContexts

Changes

0.3.1:
* Export Labels class.

0.3.1:
* Add Subset class.

0.3.0:
* Put labels in its own class.
* Change type of labels to take a Proxy.

0.2.0:
* Add "reflect" and "labels" functions.
* Drop support for GHC <8.

0.1.2:
* Add docs for "project" function.

0.1.1:
* Add "project" function.

0.1.0:
* Drop the convenience accessor #foo. Must use get #foo

0.0.0:
* First version
Depends on 2 packages:
Used by 1 package:
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