Hey <@U4DB4PJ72> Like Alberto suggested if you’re...

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[simon.vergauwen]

Hey @melatonina

Like Alberto suggested if you’re working concretely with Either it’s easier to just use Either.fx. In case you want to write polymorphic code using the typeclasses, it requires a slightly different syntax. Since depending on which typeclass you use, Monad, MonadThrow, Async, Concurrent etc you get a more or less powerful DSL enabled.

Either.monad<Exception>().fx.monad {
  !mapN(fa, fb) { a, b -> a + b }
}

IO.concurrent().fx.concurrent {
  // Concurrent & parallel DSL
  !parMapN(fa, fb) { a, b -> a + b } 
}

Since we already know what the most powerful powers are for Either or IO we can already hide that additional boilerplate for you.

We achieve these different powers by using different receivers in the DSL. MonadSyntax for Either & ConcurrentSyntax for IO in this example.