# JSON Decode Exploration [![Build Status](https://travis-ci.org/zwilias/json-decode-exploration.svg?branch=master)](https://travis-ci.org/zwilias/json-decode-exploration)

I should really write some elevator-pitch style examples to include here. Oh
well.

Made with ❤️  and released under BSD3. My eternal thanks to
[@michaeljones](https://github.com/michaeljones) for his invaluable feedback and
continued discovery of edge-cases and bugs!

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## Changelog

### 4.3.0

#### Added

- `Json.Decode.Exploration`:
    - `isObject` and `isArray`: ascertainments about structure without using
      contained values

#### Changed

- `Json.Decode.Exploration.Pipeline`:
    - `optional` and `optionalAt` now use `isObject` to prevent marking unused
      contained values as having been used.

### 4.2.1

#### Changed

- `Json.Decode.Exploration.Pipeline.optional` and `optionalAt` now error when
  used on something that is not an object. The clue is that each field in the
  path is optional in the existential sense - if it simply does not exist, we
  dutifully use the provided fallback. However, if a field exists but does not
  point to an object, we now error out instead.
- as a side effect, both of the above now correctly mark empty objects as having
  been used, rather than giving a warning when using `optional` on an empty
  object.
  
### 4.2.0

#### Added

- `Json.Decode.Exploration.check`: verify the value of a field while decoding
- `Json.Decode.Exploration.Pipeline`:
    - `checked` and `checkedAt`: verify values during decoding
    - `ignored` and `ignoredAt`: completely ignore values during decoding

#### Changed

Increased test coverage of `Json.Decode.Exploration.Pipeline`.

### 4.1.2

#### Fixed

`BadField` errors weren't properly traced through the stack.

#### Changed

Increase test coverage of `Json.Decode.Exploration`.