How to write a Play JSON writes converter for a case class with a single nullable member

Question

In Play 2.3, I have a case class with a single optional double member:

case class SomeClass(foo: Option[Double])

I need a JSON write conver

Answer 1

The easy way is:

import play.api.libs.json.Json

implicit val fmt = Json.format[SomeClass]

Which uses a macro to auto-generate the json format for you. Beats implementing writes directly.