Typeclass instances on companion objects rather than package (#4)

ninny/src/io/github/kag0/ninny/Auto.scala

@@ -1,3 +1,19 @@
 package io.github.kag0.ninny
 
+import shapeless.{LabelledGeneric, Lazy}
+
+trait AutoToJson {
+  implicit def lgToJson[A, Head](implicit
+      generic: LabelledGeneric.Aux[A, Head],
+      headToJson: Lazy[ToSomeJsonObject[Head]]
+  ) = ToJsonAuto.labelledGenericToJson[A, Head].toJson
+}
+
+trait AutoFromJson {
+  implicit def lgFromJson[A, Head](implicit
+      generic: LabelledGeneric.Aux[A, Head],
+      headFromJson: Lazy[FromJson[Head]]
+  ) = FromJsonAuto.labelledGenericFromJson[A, Head].fromJson
+}
+
 object Auto extends AutoToJson with AutoFromJson

ninny/src/io/github/kag0/ninny/FromJson.scala

@@ -13,7 +13,7 @@ trait FromJson[A] {
   def map[B](f: A => B): FromJson[B] = from(_).map(f)
 }
 
-object FromJson {
+object FromJson extends FromJsonInstances {
   def apply[A: FromJson]: FromJson[A] = implicitly[FromJson[A]]
   def fromSome[A](read: JsonValue => Try[A]): FromJson[A] = {
     case Some(json) => read(json)

ninny/src/io/github/kag0/ninny/FromJsonInstances.scala

@@ -110,11 +110,10 @@ trait FromJsonInstances {
     FromJson.fromSome(
       _.to[String].flatMap(s => Try(ZonedDateTime.parse(s)))
     )
+  implicit val hNilFromJson: FromJson[HNil] = _ => Success(HNil)
 
   import shapeless.::
 
-  implicit val hNilFromJson: FromJson[HNil] = _ => Success(HNil)
-
   implicit def recordFromJson[Key <: Symbol, Head, Tail <: HList](implicit
       witness: Witness.Aux[Key],
       headFromJson: Lazy[FromJson[Head]],
@@ -131,18 +130,14 @@ trait FromJsonInstances {
       } yield field[Key](head) :: tail
     }
   }
-
-  implicit def labelledGenericFromJson[A, Head](implicit
-      generic: LabelledGeneric.Aux[A, Head],
-      headFromJson: Lazy[FromJson[Head]]
-  ) = new FromJsonAuto[A](headFromJson.value.from(_).map(generic.from))
 }
+object FromJsonInstances extends FromJsonInstances
 
 class FromJsonAuto[A](val fromJson: FromJson[A]) extends AnyVal
+object FromJsonAuto {
 
-trait AutoFromJson {
-  implicit def lgFromJson[A, Head](implicit
+  implicit def labelledGenericFromJson[A, Head](implicit
       generic: LabelledGeneric.Aux[A, Head],
       headFromJson: Lazy[FromJson[Head]]
-  ) = labelledGenericFromJson[A, Head].fromJson
+  ) = new FromJsonAuto[A](headFromJson.value.from(_).map(generic.from))
 }

ninny/src/io/github/kag0/ninny/ToJson.scala

@@ -8,6 +8,8 @@ trait ToJsonValue[A, +Json <: JsonValue] {
   def contramap[B](f: B => A): ToJsonValue[B, Json] = b => to(f(b))
 }
 
+object ToJsonValue extends ToJsonInstances
+
 object ToJson {
   def apply[A: ToJson]: ToJson[A] = implicitly[ToJson[A]]
 

ninny/src/io/github/kag0/ninny/ToJsonInstances.scala

@@ -71,18 +71,14 @@ trait ToJsonInstances {
       }
     }
   }
-
-  implicit def labelledGenericToJson[A, Head](implicit
-      generic: LabelledGeneric.Aux[A, Head],
-      headToJson: Lazy[ToSomeJsonObject[Head]]
-  ) = new ToJsonAuto[A](a => headToJson.value.toSome(generic.to(a)))
 }
+object ToJsonInstances extends ToJsonInstances
 
 class ToJsonAuto[A](val toJson: ToSomeJsonObject[A]) extends AnyVal
+object ToJsonAuto {
 
-trait AutoToJson {
-  implicit def lgToJson[A, Head](implicit
+  implicit def labelledGenericToJson[A, Head](implicit
       generic: LabelledGeneric.Aux[A, Head],
       headToJson: Lazy[ToSomeJsonObject[Head]]
-  ) = labelledGenericToJson[A, Head].toJson
+  ) = new ToJsonAuto[A](a => headToJson.value.toSome(generic.to(a)))
 }

ninny/src/io/github/kag0/ninny/package.scala

@@ -4,7 +4,7 @@ import io.github.kag0.ninny.ast.{JsonArray, JsonObject, JsonValue}
 import scala.language.dynamics
 import scala.util.Try
 
-package object ninny extends ToJsonInstances with FromJsonInstances {
+package object ninny {
 
   type ToJson[A]           = ToJsonValue[A, JsonValue]
   type ToJsonObject[A]     = ToJsonValue[A, JsonObject]