Merge pull request #22 from slamdata/phantom-responsetype

Use phantom type instead of Proxy for ResponseType

Author: jdegoes

bower.json

@@ -24,7 +24,6 @@
     "purescript-dom": "~0.1.2",
     "purescript-foreign": "~0.4.2",
     "purescript-integers": "~0.0.1",
-    "purescript-nullable": "~0.1.1",
-    "purescript-proxy": "~0.1.0"
+    "purescript-nullable": "~0.1.1"
   }
 }

docs/Network.HTTP.Affjax.Response.md

@@ -5,30 +5,32 @@
 #### `ResponseType`
 
 ``` purescript
-data ResponseType
+data ResponseType a
 ```
 
 Valid response types for an AJAX request. This is used to determine the
-`ResponseContent` type for a request.
+`ResponseContent` type for a request. The `a` type variable is a phantom
+type used to associate the `ResponseType` with a particular instance of
+`Respondable`.
 
 #### `eqResponseType`
 
 ``` purescript
-instance eqResponseType :: Eq ResponseType
+instance eqResponseType :: Eq (ResponseType a)
 ```
 
 
 #### `showResponseType`
 
 ``` purescript
-instance showResponseType :: Show ResponseType
+instance showResponseType :: Show (ResponseType a)
 ```
 
 
 #### `responseTypeToString`
 
 ``` purescript
-responseTypeToString :: ResponseType -> String
+responseTypeToString :: forall a. ResponseType a -> String
 ```
 
 
@@ -45,7 +47,7 @@ Type representing content types that be received from an XHR request
 
 ``` purescript
 class Respondable a where
-  responseType :: Proxy a -> ResponseType
+  responseType :: ResponseType a
   fromResponse :: ResponseContent -> F a
 ```
 

src/Network/HTTP/Affjax.purs

@@ -27,7 +27,6 @@ import Network.HTTP.Method (Method(..), methodToString)
 import Network.HTTP.RequestHeader (RequestHeader(), requestHeaderName, requestHeaderValue)
 import Network.HTTP.ResponseHeader (ResponseHeader(), responseHeader)
 import Network.HTTP.StatusCode (StatusCode())
-import Type.Proxy (Proxy(..))
 
 -- | The effect type for AJAX requests made with Affjax.
 foreign import data AJAX :: !
@@ -130,7 +129,7 @@ affjax' req eb cb =
          , url: req.url
          , headers: (\h -> { field: requestHeaderName h, value: requestHeaderValue h }) <$> req.headers
          , content: toNullable (toRequest <$> req.content)
-         , responseType: responseTypeToString $ responseType (Proxy :: Proxy b)
+         , responseType: responseTypeToString (responseType :: ResponseType b)
          , username: toNullable req.username
          , password: toNullable req.password
          }

src/Network/HTTP/Affjax/Response.purs

@@ -14,15 +14,17 @@ import Type.Proxy (Proxy())
 import qualified Data.ArrayBuffer.Types as A
 
 -- | Valid response types for an AJAX request. This is used to determine the
--- | `ResponseContent` type for a request.
-data ResponseType
+-- | `ResponseContent` type for a request. The `a` type variable is a phantom
+-- | type used to associate the `ResponseType` with a particular instance of
+-- | `Respondable`.
+data ResponseType a
   = ArrayBufferResponse
   | BlobResponse
   | DocumentResponse
   | JSONResponse
   | StringResponse
 
-instance eqResponseType :: Eq ResponseType where
+instance eqResponseType :: Eq (ResponseType a) where
   (==) ArrayBufferResponse ArrayBufferResponse = true
   (==) BlobResponse        BlobResponse        = true
   (==) DocumentResponse    DocumentResponse    = true
@@ -31,14 +33,14 @@ instance eqResponseType :: Eq ResponseType where
   (==) _ _ = false
   (/=) x y = not (x == y)
 
-instance showResponseType :: Show ResponseType where
+instance showResponseType :: Show (ResponseType a) where
   show ArrayBufferResponse = "ArrayBufferResponse"
   show BlobResponse = "BlobResponse"
   show DocumentResponse = "DocumentResponse"
   show JSONResponse = "JSONResponse"
   show StringResponse = "StringResponse"
 
-responseTypeToString :: ResponseType -> String
+responseTypeToString :: forall a. (ResponseType a) -> String
 responseTypeToString ArrayBufferResponse = "arraybuffer"
 responseTypeToString BlobResponse = "blob"
 responseTypeToString DocumentResponse = "document"
@@ -50,25 +52,25 @@ responseTypeToString StringResponse = "text"
 type ResponseContent = Foreign
 
 class Respondable a where
-  responseType :: Proxy a -> ResponseType
+  responseType :: ResponseType a
   fromResponse :: ResponseContent -> F a
 
 instance responsableBlob :: Respondable Blob where
-  responseType _ = BlobResponse
+  responseType = BlobResponse
   fromResponse = unsafeReadTagged "Blob"
 
 instance responsableDocument :: Respondable Document where
-  responseType _ = DocumentResponse
+  responseType = DocumentResponse
   fromResponse = unsafeReadTagged "Document"
 
 instance responsableJSON :: Respondable Foreign where
-  responseType _ = JSONResponse
+  responseType = JSONResponse
   fromResponse = Right
 
 instance responsableString :: Respondable String where
-  responseType _ = StringResponse
+  responseType = StringResponse
   fromResponse = readString
 
 instance responsableUnit :: Respondable Unit where
-  responseType _ = StringResponse
+  responseType = StringResponse
   fromResponse = const (Right unit)