Aeson combinators for dead simple JSON decoding

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BSD-3-Clause licensed and maintained by Marek Fajkus
This version can be pinned in stack with:aeson-combinators-,2669

Module documentation for

Aeson Combinators

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Low overhead value space Decoder on top of Aeson’s Parser for combinator style decoding.

This library is compatible with GHC as well as recent versions of GHCJS.

Encoding to JSON is currently not supported but might be added in the future version.

I wrote a blob post describing what this library attempts to solve.


Decoder a type is a function Value -> Parser a the same as fromJSON member function of FromJSON class. This means there should be near zero overhead. Aeson types and functions are reused where possible. Similarly Encoder a type follow toJSON from ToJSON type class.


(c) 2020 Marek Fajkus BSD-3-Clause


Revision history for aeson-combinators – 2020-10-24

  • Encode module for encoding – 2020-10-11

  • Combinators for dealing with failure
  • oneOf function
  • parseMaybe and parseEither
  • Documentation improvements – 2020-03-08

  • Add README to extra source files – 2020-03-08

  • GHCJS compatibility – 2020-03-01

  • Fixes and improvements in documentation
  • Add source-repository to cabal file – 2020-02-29

  • First version. Released on an unsuspecting world.