Do monad transformers apply to getting JSON from services?

Question

I have a Play! 2 for Scala application that needs to retrieve some data in JSON format from an external service.

The Play! framework allows to make HTTP requests asynchr

Answer 1

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edit:

Okay, you can simply use the scalaz.OptionT here:

val x = optionT(Promise { /* api call */ some("""{ "foo": "bar" }""") })
val mapped = x.map(Json.parse).run // run return the resulting Promise[Option[T]]