# Aeson Combinators

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[**Low overhead**](#performance) 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**.

I wrote a [blob post](https://turbomack.github.io/posts/2020-02-21-value-space-decoding-for-aeson.html)
describing what this library attempts to solve.

## Performance

`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.

## License

(c) 2020 Marek Fajkus
BSD-3-Clause