# persistent-instances

Small `persistent` instance helpers for useful types, split into public sublibraries, so users can depend on only the pieces they need. (e.g. if you only use `uuid`, you won't need to depend on vector dependencies).

These are useful but there are no official instances defined for them.

Warning: these are orphan instances, be careful when using them in public libraries.

A future alternative to orphans would be defining a library specific `newtype` wrapper.

## Available sublibraries

- `persistent-instances:uuid`
  Exposes `Database.Persist.UUID`, contains instances for `UUID` in library `uuid`.

- `persistent-instances:postgresql-vector`
  Exposes `Database.Persist.Postgresql.Vector`, contains instances for `Data.Vector.Unboxed.Sized` in `vector-sized`, suitable for `pg_vector` extension.

## Usage

Add one or both sublibraries to `build-depends`:

```cabal
build-depends:
    persistent-instances:uuid
```

```cabal
build-depends:
    persistent-instances:postgresql-vector
```

Then import the corresponding module:

```haskell
import Database.Persist.UUID
```

```haskell
import Database.Persist.Postgresql.Vector
```