For generic decoding, `Decode (Foo a)` needs a `Decode a` constraint,
but it *doesn't* need a `Generic a` constraint.

Adding in this unnecessary constraint creates needless problems like,
"there isn't an instance for `Generic String _`."

PureScript isn't happy with eta-reduced typeclass instances on recursive
types. We have to make the function application explicit.

…y (Container A)`.

The generated code will include an `Eq a =>` constraint.

* Sum types where every constructor has zero arguments. Aeson has
special handling for these.

For generic decoding, `Decode (Foo a)` needs a `Decode a` constraint,
but it *doesn't* need a `Generic a` constraint.

Adding in this unnecessary constraint creates needless problems like,
"there isn't an instance for `Generic String _`."

…xy (Container A)`.

The generated code will include an `Ord a =>` constraint.

It turns out you can't eta-reduce typeclass instances for
recursively-defined typeclasses in PureScript. That is:

`show = genericShow`

...has to be replaced with:

`show x = genericShow`

...to work reliably.

See: purescript/purescript#2975

That is, `(genericShow <*> mkSumType) (Proxy @(Foo A))` will generate:

```
instance showFoo :: Show a => Show (Foo a) where
  show = genericShow
```

...whereas before it would have missed out the `Show a` constraint.

Eq1

fix build of `RoundTrip` test

format tweaks

remove deprecated `Generics` library

WIP fixing tests

copy unit tests from IOHK fork

fixing tests

clean-up

fix Newtype, Lens imports

fixing tests

fix

remove duplicate tests

improve `CodeGenSwitches`

work-in-progress `purescript-argonaut-aeson-generic` instances

https://pursuit.purescript.org/packages/purescript-argonaut-aeson-generic/0.4.1

fix argonaut-aeson-generic support

improve ordering of printed instances

fix spaces

prisms and lenses

more test fixing

fix `Maybe(..)` import

fix line printing

fix Newtype imports

fix explicit aliased imports

fix `Lens'` and `Newtype` imports

fix example

fix RoundTrip test

lint

disable certain warnings

type parameters in `example`

`spago` compiles example successfully

`DecodeJsonField` eskimor@c55622e is not
supported yet

We want the result to be the same as https://github.com/eskimor/purescript-bridge/blob/ee0582aed3e5b62ea25b1079dee2c31b949381e7/example/src/Types.purs#L88-L93

latest `haskell-flake`

also uses https://github.com/thomashoneyman/purescript-overlay