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1. urlEncodeAsFormStable :: ToForm a => a -> ByteString

   http-api-data	Web.FormUrlEncoded

   This is a convenience function for encoding a datatype that has instance of ToForm directly to a application/x-www-form-urlencoded ByteString. This is effectively urlEncodeFormStable . toForm.

   >>> urlEncodeAsFormStable Person {name = "Dennis", age = 22}
   "age=22&name=Dennis"
   

2. urlEncodeForm :: Form -> ByteString

   http-api-data	Web.FormUrlEncoded

   Encode a Form to an application/x-www-form-urlencoded ByteString. _NOTE:_ this encoding is unstable and may result in different key order (but not values). For a stable encoding see urlEncodeFormStable.

3. urlEncodeFormStable :: Form -> ByteString

   http-api-data	Web.FormUrlEncoded

   Encode a Form to an application/x-www-form-urlencoded ByteString. For an unstable (but faster) encoding see urlEncodeForm. Key-value pairs get encoded to key=value and separated by &:

   >>> urlEncodeFormStable [("name", "Julian"), ("lastname", "Arni")]
   "lastname=Arni&name=Julian"
   

   Keys with empty values get encoded to just key (without the = sign):

   >>> urlEncodeFormStable [("is_test", "")]
   "is_test"
   

   Empty keys are allowed too:

   >>> urlEncodeFormStable [("", "foobar")]
   "=foobar"
   

   However, if both key and value are empty, the key-value pair is ignored. (This prevents urlDecodeForm . urlEncodeFormStable from being a true isomorphism).

   >>> urlEncodeFormStable [("", "")]
   ""
   

   Everything is escaped with escapeURIString isUnreserved:

   >>> urlEncodeFormStable [("fullname", "Andres Löh")]
   "fullname=Andres%20L%C3%B6h"
   

4. class FromForm a

   http-api-data	Web.Internal.FormUrlEncoded

   Parse Form into a value. An example type and instance:

   data Person = Person
   { name :: String
   , age  :: Int }
   
   instance FromForm Person where
   fromForm f = Person
   <$> parseUnique "name" f
   <*> parseUnique "age"  f
   

   Instead of manually writing FromForm instances you can use a default generic implementation of fromForm. To do that, simply add deriving Generic clause to your datatype and declare a FromForm instance for your datatype without giving definition for fromForm. For instance, the previous example can be simplified into this:

   data Person = Person
   { name :: String
   , age  :: Int
   } deriving (Generic)
   
   instance FromForm Person
   

   The default implementation of fromForm is genericFromForm. It only works for records and it will use parseQueryParam for each field's value.

5. class FromFormKey k

   http-api-data	Web.Internal.FormUrlEncoded

   Typeclass for types that can be parsed from keys of a Form. This is the reverse of ToFormKey.

6. class GFromForm (t :: k) (f :: Type -> Type)

   http-api-data	Web.Internal.FormUrlEncoded

   No documentation available.

7. class GToForm (t :: k) (f :: Type -> Type)

   http-api-data	Web.Internal.FormUrlEncoded

   No documentation available.

8. class ToForm a

   http-api-data	Web.Internal.FormUrlEncoded

   Convert a value into Form. An example type and instance:

   {-# LANGUAGE OverloadedLists #-}
   
   data Person = Person
   { name :: String
   , age  :: Int }
   
   instance ToForm Person where
   toForm person =
   [ ("name", toQueryParam (name person))
   , ("age", toQueryParam (age person)) ]
   

   Instead of manually writing ToForm instances you can use a default generic implementation of toForm. To do that, simply add deriving Generic clause to your datatype and declare a ToForm instance for your datatype without giving definition for toForm. For instance, the previous example can be simplified into this:

   data Person = Person
   { name :: String
   , age  :: Int
   } deriving (Generic)
   
   instance ToForm Person
   

   The default implementation of toForm is genericToForm.

9. class ToFormKey k

   http-api-data	Web.Internal.FormUrlEncoded

   Typeclass for types that can be used as keys in a Form-like container (like Map).

10. defaultFormOptions :: FormOptions

    http-api-data	Web.Internal.FormUrlEncoded

    Default encoding FormOptions.

    FormOptions
    { fieldLabelModifier = id
    }
    

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