Reads for recursive search paths

gistfile1.scala

// Reads for recursive path
def recursiveSearchReads[T : Reads](path: JsPath) = Reads[Seq[T]] { json =>
  path.apply(json).map(_.validate[T]).foldLeft[JsResult[Seq[T]]](JsSuccess(Nil)) {
    case (JsError(a), JsError(b)) => JsError(a ++ b)
    case (err: JsError, _) => err
    case (_, err: JsError) => err
    case (JsSuccess(ts, _), JsSuccess(t, _)) => JsSuccess(ts :+ t)
  }.repath(path)
}

// Reads for recursive path of arrays, flattened
def recursiveSearchReadsFlatten[T : Reads](path: JsPath) = Reads[Seq[T]] { json =>
  path.apply(json).map(_.validate[Seq[T]]).reduceLeft[JsResult[Seq[T]]] {
    case (JsError(a), JsError(b)) => JsError(a ++ b)
    case (err: JsError, _) => err
    case (_, err: JsError) => err
    case (JsSuccess(a, _), JsSuccess(b, _)) => JsSuccess(a ++ b)
  }.repath(path)
}

Reads for recursive paths... perhaps we should add these methods to JsPath, currently, you can't:

(__ \\ "foo").read[Seq[Foo]]

But with this you can:

recursiveSearchReads[Foo](__ \\ "foo")

Something else that would be good is a simple way to Seq[JsResult[T]] => JsResult[Seq[T]], in case the above was not powerful enough for you, you could use that method to implement the above in far less code.

Actually we don't have it because nobody asked for it IMHO :D

The equivalent of Future.sequence for JsResult would be cool too.
I thought I had written it somewhere but I don't find it anymore!

I also believe some Reads based on JsZipper would be far more powerful...