`InnerResponse` is now a type param instead of member, allowing better error messages through `cask.internal.Conversion`:

```
Cannot return java.io.ByteArrayInputStream as a cask.model.Response[cask.endpoints.JsonData]
```

10 files changed, 25 insertions, 28 deletions

diff --git a/cask/src/cask/endpoints/FormEndpoint.scala b/cask/src/cask/endpoints/FormEndpoint.scala
index 436bed4..264c169 100644
--- a/cask/src/cask/endpoints/FormEndpoint.scala
+++ b/cask/src/cask/endpoints/FormEndpoint.scala
@@ -43,8 +43,8 @@ object FormReader{
     def read(ctx: Request, label: String, input: Seq[FormEntry]) = input.map(_.asInstanceOf[FormFile])
   }
 }
-class postForm(val path: String, override val subpath: Boolean = false) extends Endpoint {
-  type InnerReturned = Response.Raw
+class postForm(val path: String, override val subpath: Boolean = false)
+  extends Endpoint[Response.Raw] {
 
   val methods = Seq("post")
   type Input = Seq[FormEntry]
diff --git a/cask/src/cask/endpoints/JsonEndpoint.scala b/cask/src/cask/endpoints/JsonEndpoint.scala
index 3b3b095..2e3373f 100644
--- a/cask/src/cask/endpoints/JsonEndpoint.scala
+++ b/cask/src/cask/endpoints/JsonEndpoint.scala
@@ -39,8 +39,8 @@ object JsonData extends DataCompanion[JsonData]{
   }
 }
 
-class postJson(val path: String, override val subpath: Boolean = false) extends Endpoint{
-  type InnerReturned = Response[JsonData]
+class postJson(val path: String, override val subpath: Boolean = false)
+  extends Endpoint[Response[JsonData]]{
   val methods = Seq("post")
   type Input = ujson.Value
   type InputParser[T] = JsReader[T]
@@ -79,8 +79,8 @@ class postJson(val path: String, override val subpath: Boolean = false) extends
   def wrapPathSegment(s: String): Input = ujson.Str(s)
 }
 
-class getJson(val path: String, override val subpath: Boolean = false) extends Endpoint{
-  type InnerReturned = Response[JsonData]
+class getJson(val path: String, override val subpath: Boolean = false)
+  extends Endpoint[Response[JsonData]]{
   val methods = Seq("get")
   type Input = Seq[String]
   type InputParser[T] = QueryParamReader[T]
diff --git a/cask/src/cask/endpoints/StaticEndpoints.scala b/cask/src/cask/endpoints/StaticEndpoints.scala
index 401f845..bf99d09 100644
--- a/cask/src/cask/endpoints/StaticEndpoints.scala
+++ b/cask/src/cask/endpoints/StaticEndpoints.scala
@@ -3,8 +3,7 @@ package cask.endpoints
 import cask.main.Endpoint
 import cask.model.Request
 
-class staticFiles(val path: String) extends Endpoint{
-  type InnerReturned = String
+class staticFiles(val path: String) extends Endpoint[String]{
   val methods = Seq("get")
   type Input = Seq[String]
   type InputParser[T] = QueryParamReader[T]
@@ -22,8 +21,8 @@ class staticFiles(val path: String) extends Endpoint{
   def wrapPathSegment(s: String): Input = Seq(s)
 }
 
-class staticResources(val path: String, resourceRoot: ClassLoader = getClass.getClassLoader) extends Endpoint{
-  type InnerReturned = String
+class staticResources(val path: String, resourceRoot: ClassLoader = getClass.getClassLoader)
+  extends Endpoint[String]{
   val methods = Seq("get")
   type Input = Seq[String]
   type InputParser[T] = QueryParamReader[T]
diff --git a/cask/src/cask/endpoints/WebEndpoints.scala b/cask/src/cask/endpoints/WebEndpoints.scala
index 7cac4f5..b52b290 100644
--- a/cask/src/cask/endpoints/WebEndpoints.scala
+++ b/cask/src/cask/endpoints/WebEndpoints.scala
@@ -7,8 +7,7 @@ import cask.model.{Request, Response}
 import collection.JavaConverters._
 
 
-trait WebEndpoint extends Endpoint{
-  type InnerReturned = Response.Raw
+trait WebEndpoint extends Endpoint[Response.Raw]{
   type Input = Seq[String]
   type InputParser[T] = QueryParamReader[T]
   def wrapFunction(ctx: Request,
diff --git a/cask/src/cask/endpoints/WebSocketEndpoint.scala b/cask/src/cask/endpoints/WebSocketEndpoint.scala
index 5f35832..ca2854f 100644
--- a/cask/src/cask/endpoints/WebSocketEndpoint.scala
+++ b/cask/src/cask/endpoints/WebSocketEndpoint.scala
@@ -13,8 +13,8 @@ object WebsocketResult{
   implicit class Listener(val value: WebSocketConnectionCallback) extends WebsocketResult
 }
 
-class websocket(val path: String, override val subpath: Boolean = false) extends cask.main.BaseEndpoint{
-  type InnerReturned = WebsocketResult
+class websocket(val path: String, override val subpath: Boolean = false)
+  extends cask.main.BaseEndpoint[WebsocketResult]{
   val methods = Seq("websocket")
   type Input = Seq[String]
   type InputParser[T] = QueryParamReader[T]
diff --git a/cask/src/cask/internal/Conversion.scala b/cask/src/cask/internal/Conversion.scala
index e6a5a47..8d8ee3a 100644
--- a/cask/src/cask/internal/Conversion.scala
+++ b/cask/src/cask/internal/Conversion.scala
@@ -2,8 +2,8 @@ package cask.internal
 
 import scala.annotation.implicitNotFound
 
-@implicitNotFound("Cannot return ${T} as a ${V} response")
+@implicitNotFound("Cannot return ${T} as a ${V}")
 class Conversion[T, V](val f: T => V)
 object Conversion{
-  def create[T, V](implicit f: T => V) = new Conversion(f)
+  implicit def create[T, V](implicit f: T => V) = new Conversion(f)
 }
diff --git a/cask/src/cask/main/Decorators.scala b/cask/src/cask/main/Decorators.scala
index 28d44f5..e395d5b 100644
--- a/cask/src/cask/main/Decorators.scala
+++ b/cask/src/cask/main/Decorators.scala
@@ -9,7 +9,7 @@ import cask.model.{Request, Response}
   * Annotates a Cask endpoint that returns a HTTP [[Response]]; similar to a
   * [[Decorator]] but with additional metadata and capabilities.
   */
-trait Endpoint extends BaseEndpoint {
+trait Endpoint[InnerReturned] extends BaseEndpoint[InnerReturned] {
   type OuterReturned = Router.Result[Response.Raw]
 }
 
@@ -17,7 +17,7 @@ trait Endpoint extends BaseEndpoint {
   * An [[Endpoint]] that may return something else than a HTTP response, e.g.
   * a websocket endpoint which may instead return a websocket event handler
   */
-trait BaseEndpoint extends BaseDecorator{
+trait BaseEndpoint[InnerReturned] extends BaseDecorator[InnerReturned]{
   /**
     * What is the path that this particular endpoint matches?
     */
@@ -55,10 +55,9 @@ trait BaseEndpoint extends BaseDecorator{
 /**
   * A [[Decorator]] that may deal with values other than HTTP [[Response]]s
   */
-trait BaseDecorator{
+trait BaseDecorator[InnerReturned]{
   type Input
   type InputParser[T] <: ArgReader[Input, T, Request]
-  type InnerReturned
   type Delegate = Map[String, Input] => Router.Result[InnerReturned]
   type OuterReturned <: Router.Result[Any]
   def wrapFunction(ctx: Request, delegate: Delegate): OuterReturned
@@ -76,10 +75,9 @@ trait BaseDecorator{
   * to `wrapFunction`, which takes a `Map` representing any additional argument
   * lists (if any).
   */
-trait Decorator extends BaseDecorator{
+trait Decorator extends BaseDecorator[Response.Raw]{
   type OuterReturned = Router.Result[Response.Raw]
   type Input = Any
-  type InnerReturned = Response.Raw
   type InputParser[T] = NoOpParser[Input, T]
 }
 
diff --git a/cask/src/cask/main/Main.scala b/cask/src/cask/main/Main.scala
index 7128006..c3a4ace 100644
--- a/cask/src/cask/main/Main.scala
+++ b/cask/src/cask/main/Main.scala
@@ -94,7 +94,8 @@ abstract class BaseMain{
                 case head :: rest =>
                   head.wrapFunction(
                     ctx,
-                    args => rec(rest, args :: bindings).asInstanceOf[Router.Result[head.InnerReturned]]
+                    args => rec(rest, args :: bindings)
+                      .asInstanceOf[cask.internal.Router.Result[cask.model.Response.Raw]]
                   )
 
                 case Nil =>
diff --git a/cask/src/cask/main/Routes.scala b/cask/src/cask/main/Routes.scala
index a4660a9..5b02542 100644
--- a/cask/src/cask/main/Routes.scala
+++ b/cask/src/cask/main/Routes.scala
@@ -8,7 +8,7 @@ import language.experimental.macros
 
 object Routes{
   case class EndpointMetadata[T](decorators: Seq[Decorator],
-                                 endpoint: BaseEndpoint,
+                                 endpoint: BaseEndpoint[_],
                                  entryPoint: EntryPoint[T, _])
   case class RoutesEndpointsMetadata[T](value: EndpointMetadata[T]*)
   object RoutesEndpointsMetadata{
@@ -19,15 +19,15 @@ object Routes{
 
       val routeParts = for{
         m <- c.weakTypeOf[T].members
-        val annotations = m.annotations.filter(_.tree.tpe <:< c.weakTypeOf[BaseDecorator]).reverse
+        val annotations = m.annotations.filter(_.tree.tpe <:< c.weakTypeOf[BaseDecorator[_]]).reverse
         if annotations.nonEmpty
       } yield {
-        if(!(annotations.head.tree.tpe <:< weakTypeOf[BaseEndpoint])) c.abort(
+        if(!(annotations.head.tree.tpe <:< weakTypeOf[BaseEndpoint[_]])) c.abort(
           annotations.head.tree.pos,
           s"Last annotation applied to a function must be an instance of Endpoint, " +
           s"not ${annotations.head.tree.tpe}"
         )
-        val allEndpoints = annotations.filter(_.tree.tpe <:< weakTypeOf[BaseEndpoint])
+        val allEndpoints = annotations.filter(_.tree.tpe <:< weakTypeOf[BaseEndpoint[_]])
         if(allEndpoints.length > 1) c.abort(
           annotations.head.tree.pos,
           s"You can only apply one Endpoint annotation to a function, not " +
diff --git a/cask/src/cask/package.scala b/cask/src/cask/package.scala
index 51aaaf6..c3909ec 100644
--- a/cask/src/cask/package.scala
+++ b/cask/src/cask/package.scala
@@ -38,6 +38,6 @@ package object cask {
   val Routes = main.Routes
   type Main = main.Main
   type Decorator = main.Decorator
-  type Endpoint = main.Endpoint
+  type Endpoint[InnerReturned] = main.Endpoint[InnerReturned]
 
 }