Move Op from parameter to member in smithy4s.Service #567
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Similarly to what happened with `cats.Parallel`, the Operation type of `smithy4s.Service` can be moved from type-parameter to type-member, which helps implicit search.
| implicit val serviceInstance: Service[Alg, Op] = this | ||
| val service = this | ||
| trait Service[Alg[_[_, _, _, _, _]]] extends FunctorK5[Alg] with Service.Provider[Alg] { | ||
| type Operation[E, I, O, SI, SO] |
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allows for a long name :D (not that it was not allowed of course, just that the long version in the type parameter as just so annoying
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sooo why didn't CI fail on any of the last commits? |
The CI, as currently configured, doesn't run unless the PR is targeting main (afaik) |
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we should probably change that, then :) |
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This reverts commit 768ca6e.
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Problem was that PR trigger was using the |
| trait Service[Alg[_[_, _, _, _, _]], Op[_, _, _, _, _]] extends FunctorK5[Alg] with Service.Provider[Alg, Op] { | ||
| implicit val serviceInstance: Service[Alg, Op] = this | ||
| val service = this | ||
| trait Service[Alg[_[_, _, _, _, _]]] extends FunctorK5[Alg] with Service.Provider[Alg] { |
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Most of the changes derive from this line : the Op is moved from type-parameter to type-member.
| type Endpoint[I, E, O, SI, SO] = smithy4s.Endpoint[Operation, I, E, O, SI, SO] | ||
| type Interpreter[F[_, _, _, _, _]] = PolyFunction5[Operation, F] | ||
| type FunctorInterpreter[F[_]] = PolyFunction5[Operation, kinds.Kind1[F]#toKind5] | ||
| type BiFunctorInterpreter[F[_, _]] = PolyFunction5[Operation, kinds.Kind2[F]#toKind5] |
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the type aliases above are path-dependant (by virtue of depending on the Operation abstract type member) , it means we can ascribe service.Endpoint, service.Interpreter, etc etc. This allows to simplify up a number of verbose ascriptions here and there.
| service, | ||
| service.toPolyFunction[Kind1[F]#toKind5](impl), |
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the implementation was prematurely turned into a polymorphic function
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| def apply[Alg[_[_, _, _, _, _]]](implicit ev: Service[Alg]): ev.type = ev | ||
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| type Aux[Alg[_[_, _, _, _, _]], Op[_, _, _, _, _]] = Service[Alg]{ type Operation[I, E, O, SI, SO] = Op[I, E, O, SI, SO] } |
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the Aux pattern allows to "recover" the type parameter that was moved, in locations where it matters
Similarly to what happened with
cats.Parallel, the Operation type ofsmithy4s.Servicecan be moved from type-parameter to type-member. This simplifies type signatures for a number of public methods, and helps implicit search in some cases.