### Description
There were several places in the codebase where we would either implement a generic container, or express the need for one. This PR extracts / creates all relevant containers, and adapts the relevant parts of the code to make use of said new generic containers. More specifically, it introduces the following modules:
- `Data.Set.Extended`, for new functions on `Data.Set`
- `Data.HashMap.Strict.Multi`, for hash maps that accept multiple values
- `Data.HashMap.Strict.NonEmpty`, for hash maps that can never be constructed as empty
- `Data.Trie`, for a generic implementation of a prefix tree
This PR makes use of those new containers in the following parts of the code:
- `Hasura.GraphQL.Execute.RemoteJoin.Types`
- `Hasura.RQL.Types.Endpoint*`
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3828
GitOrigin-RevId: e6c1b971bcb3f5ab66bc91d0fa4d0e9df7a0c6c6
TL;DR
---
We go from this:
```haskell
(|
withRecordInconsistency
( (|
modifyErrA
( do
(info, dependencies) <- liftEitherA -< buildRelInfo relDef
recordDependencies -< (metadataObject, schemaObject, dependencies)
returnA -< info
)
|) (addTableContext @b table . addRelationshipContext)
)
|) metadataObject
```
to this:
```haskell
withRecordInconsistencyM metadataObject $ do
modifyErr (addTableContext @b table . addRelationshipContext) $ do
(info, dependencies) <- liftEither $ buildRelInfo relDef
recordDependenciesM metadataObject schemaObject dependencies
return info
```
Background
---
We use Haskell's `Arrows` language extension to gain some syntactic sugar when working with `Arrow`s. `Arrow`s are a programming abstraction comparable to `Monad`s.
Unfortunately the syntactic sugar provided by this language extension is not very sweet.
This PR shows how we can sometimes avoid using `Arrow`s altogether, without loss of functionality or correctness. It is a demo of a technique that can be used to cut down the amount of `Arrows`-based code in our codebase by about half.
Approach
---
Although _in general_ not every `Monad` is an `Arrow`, specific `Arrow` instantiations are exactly as powerful as their `Monad` equivalents. Otherwise they wouldn't be very equivalent, would they?
Just like `liftEither` interprets the `Either e` monad into an arbitrary monad implementing `MonadError e`, we add `interpA` which interprets certain concrete monads such as `Writer w` into specific arrows, e.g. ones satisfying `ArrowWriter w`. This means that the part of the code that only uses such interpretable effects can be written _monadically_, and then used in _arrow_ constructions down the line.
This approach cannot be used for arrow effects which do not have a monadic equivalent. In our codebase, the only instance of this is `ArrowCache m`, implemented by the `Rule m` arrow. So code written with `ArrowCache m` in the context cannot be rewritten monadically using this technique.
See also
---
- #1827
- #2210
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3543
Co-authored-by: jkachmar <8461423+jkachmar@users.noreply.github.com>
GitOrigin-RevId: eb79619c95f7a571bce99bc144ce42ee65d08505
## Description
Hopefully this is relatively self-explanatory: this change splits the helper functions we've used to extend QuickCheck from the orphan instances and generators that we have defined for unit tests. These have now been placed in `Test.QuickCheck.Extended` and `Hasura.QuickCheck.Instances`, respectively.
This change also adds some documentation to the functions defined in `Test.QuickCheck.Extended` in the spirit of similar functions defined by `Test.QuickCheck`, itself.
### Motivation
We should adhere to the existing convention of constructing "extension modules" for common libraries separately from the code that takes advantage of these.
Alone, this wouldn't be a reason to split up `Hasura.Generators`, but we should **also** follow a convention of defining **all** orphan instances in modules whose names clearly indicate that they exist solely for the purpose of exporting these orphan instances (e.g. `Hasura.QuickCheck.Instances`).
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3747
GitOrigin-RevId: fb856a790b4a39163f81481d4f900fafb1797ea6
