playframework/Play20 — comment on commit 3d6d9a83b4b69f24bb6b5e02fdb63b0288add211
File: framework/src/play/src/main/scala/play/api/libs/json/Json.scala line 10
By pk11:

there is a

def as[K, V](implicit fjs: Reads[collection.immutable.Map[K, V]]): collection.immutable.Map[K, V] = fjs.reads(this)

in JsValue that converts from as[K,V] to Map[K,V]