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Newtype for DSums representing JSON objects where one field determines the "type" of the object, and all the other data fields are stored under a distinct key. Analogous to the TaggedObject constructor in SumEncoding.

To derive FromJSON and ToJSON instances for JSON like this:

{
  "class": "fighter", -- or "rogue", or "wizard"
  "data": { ... } -- the exact fields differ depending on the value at "class".
}

You would derive the instance like this:

newtype Character = Character (DSum CharacterClass Identity)
  deriving (FromJSON, ToJSON)
  via (TaggedObject "Character" "class" "data" CharacterClass Identity)

Since: 0.1.0.0

Newtype for DSums representing JSON objects where one field determines the "type" of the object, and all the other data fields are stored at the same level.

To derive FromJSON and ToJSON instances for JSON like this:

{
  "class": "wizard", -- or "fighter", or "rogue"
  -- These fields will differ depending on the value at "class".
  "frogsLegs": 42,
  "eyesOfNewt": 9001
}

You would derive the instance like this:

newtype Character = Character (DSum CharacterClass Identity)
  deriving (FromJSON, ToJSON)
  via (TaggedObjectInline "Character" "class" CharacterClass Identity)

Since: 0.1.0.0

Newtype for DSums representing JSON objects where the object has exactly one key, and the name of that key one field determines the "type" of the object. All the other data fields are stored in the corresponding value. Analogous to the ObjectWithSingleField constructor in SumEncoding.

To derive FromJSON and ToJSON instances for JSON like this:

{
  "wizard": { -- or "fighter", or "rogue"
    -- The contents of this object will differ depending on the key.
    "frogsLegs": 42,
    "eyesOfNewt": 9001
  }
}

You would derive the instance like this:

newtype Character = Character (DSum CharacterClass Identity)
  deriving (FromJSON, ToJSON)
  via (ObjectWithSingleField "Character" CharacterClass Identity)

If the FromJSONKey/ToJSONKey instances for Some tag encode to something other than a JSON string, then a two-element array will be parsed/generated instead, like in TwoElemArray.

Since: 0.1.0.0

Newtype for DSums representing serialisation to/from a two-element array. The tag is stored in the first elemnt, and the serialised value is stored in the second. Analogous to the TwoElemArray constructor in SumEncoding.

To derive FromJSON and ToJSON instances for JSON like this:

[
  "wizard", -- or "fighter", or "rogue"
  -- The contents of this object will differ depending on the previous element.
  {
    "frogsLegs": 42,
    "eyesOfNewt": 9001
  }
]

You would derive the instance like this:

newtype Character = Character (DSum CharacterClass Identity)
  deriving (FromJSON, ToJSON)
  via (TwoElemArray "Character" CharacterClass Identity)

Since: 0.1.0.0