I am encoding a http request to a remote server as a function which takes an id and yields a Task[JValue].
I would like to convert that function into a Process1, to simplify my program (By simplify, i mean use Processes as building blocks as much as possible)
I would like to convert the function
reqDoc(id:A):Task[B]
(where A is the type of the Id, and B is the type of the response) into
reqDoc:Process1[A,B]
I don't think you want a Process1
, I think that if you were creating a Process1
out of this you would be creating a Process1[A, Task[B]]
which isn't what you want.
I think you want to create a Channel
that you can attach a Process
to that would give you a new Process
. A Channel
is just an alias for a Process
that produces effectful functions.
type Channel[+F[_],-I,O] = Process[F, I => F[O]]
Since you have one function, you are just going to create a process which produces an infinite stream of the same function, which constant
// a String => Task[Int] that we'll make a channel from
val length: String => Task[Int] = (x => Task.delay(x.length))
// a channel is just a source of functions:
val lengthChannel = Process.constant(length)
Now given a Process that produces Strings (here we'll produce just one):
val source: Process[Task,String] = Process.emit("asdf")
We can create a process by running our source through our channel
val lengths = source through lengthChannel
and we can run our process and get the length of "asdf"
scala> lengths.runLog.run
res5: scala.collection.immutable.IndexedSeq[Int] = Vector(4)