aeson-combinators: Aeson combinators for dead simple JSON decoding

[ bsd3, json, library, text, web ] [ Propose Tags ]

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

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Dependencies aeson, base (>=4 && <5), bytestring, containers, fail, scientific, text, time, time-compat, unordered-containers, uuid-types, vector, void [details]
License BSD-3-Clause
Copyright (c) 2020 Marek Fajkus
Author Marek Fajkus <>
Maintainer Marek Fajkus <>
Category Text, Web, JSON
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Source repo head: git clone
Uploaded by MarekFajkus at 2021-03-13T22:15:15Z
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Downloads 1735 total (10 in the last 30 days)
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Status Docs available [build log]
Last success reported on 2021-03-13 [all 1 reports]

Readme for aeson-combinators-

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Aeson Combinators

Build Status Build Status built with nix

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.


Decoder a type is a function Value -> Parser a the same as parseJSON 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.

Simple benchmark shows that implementation using aeson-combinators performs better than equivalent derived instance and on par (actually even slightly better though with difference in noise range) with manually implemented instance.


(c) 2020 Marek Fajkus BSD-3-Clause