Move syntax type bounds to methods #8
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ideally as a cats-accustomed user of this library, I'd like to have the following set of syntax permutations available to me:
I tested the code on this branch with this app: import cats.effect.{ExitCode, IO, IOApp}
import errata.*
import errata.instances.*
object catsInteroperability extends IOApp{
val error: Throwable = new Throwable("Boom!")
val either: Either[Throwable, Unit] = Left(error)
/*use only namespaced syntax, compiles, IDE happy*/
// def run(args: List[String]): IO[ExitCode] = {
// import errata.syntax.namespaced.*
// error.withErrata.raise[IO, Throwable, Unit] *>
// either.withErrata.liftTo[IO, Throwable] as
// ExitCode.Success
// }
/*use only non-namespaced syntax, compiles, IDE happy*/
// def run(args: List[String]): IO[ExitCode] = {
// import errata.syntax.all.*
// error.raise[IO, Throwable, Unit] as
// ExitCode.Success
// }
/*use both namespaced and non-namespaced syntax. compiles. IDE unhappy with liftTo*/
def run(args: List[String]): IO[ExitCode] = {
import errata.syntax.all.*
import errata.syntax.namespaced.*
error.raise[IO, Throwable, Unit] *>
either.withErrata.liftTo[IO, Throwable] as
ExitCode.Success
}
}observations:
I also tried doing the equivalent with the version on main. I might be missing something, but I couldn't even get the first example working. Ie, I had to manually specify everything, plus I couldn't mix and match name spaced and non name spaced syntax: import cats.effect.{ExitCode, IO, IOApp}
import errata.instances.*
object catsInteroperability extends IOApp{
val error: Throwable = new Throwable("Boom!")
val either: Either[Throwable, Unit] = Left(error)
def run(args: List[String]): IO[ExitCode] = {
import errata.syntax.namespaced.*
RaiseSyntax[IO, Throwable, Throwable](error.withErrata).raise[Unit] *>
EitherLiftSyntax[IO, Throwable, Throwable, Unit](either.withErrata).liftTo as
ExitCode.Success
}
} |
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Better discoverability, but it demands type parameters from the user
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Hey @ShahOdin! Sorry it took me so long to get back to you on this one. I tried making both syntaxes work simultaneously, but it looks like it's going to be rather complicated. I will open a separate ticket and work on it. Meanwhile in this PR the type bounds are moved into methods. The amended commit minimises the type parameters required from the user. The new variance stuff you introduces also makes some type parameters unnecessary. |
Better discoverability, but it demands type parameters from the user