Documentation

Fields of data types that represent structs, unions, and exceptions should be wrapped inside Field and tagged with the field identifier.

data Foo = Foo (Field 1 Text) (Field 2 (Maybe Int32)) deriving Generic
instance Pinchable Foo

data A = A (Field 1 Int32) | B (Field 2 Text) deriving Generic
instance Pinchable Foo

Fields which hold Maybe values are treated as optional. All fields values must be Pinchable to automatically derive a Pinchable instance for the new data type.

Gets the current value of a field.

let Foo a' _ = {- ... -}
    a = getField a'

Puts a value inside a field.

Foo (putField "Hello") (putField (Just 42))

A lens on Field wrappers for use with the lens library.

person & name . field .~ "new value"

Data types that represent Thrift enums must have one constructor for each enum item accepting an Enumeration object tagged with the corresponding enum value.

data Role = RoleUser (Enumeration 1) | RoleAdmin (Enumeration 2)
  deriving Generic
instance Pinchable Role

Convenience function to construct Enumeration objects.

let role = RoleUser enum

Represents a void result for methods.

This should be used as an element in a response union along with Field tags.

For a method,

void setValue(..) throws
  (1: ValueAlreadyExists alreadyExists,
   2: InternalError internalError)

Something similar to the following can be used.

data SetValueResponse
  = SetValueAlreadyExists (Field 1 ValueAlreadyExists)
  | SetValueInternalError (Field 2 InternalError)
  | SetValueSuccess Void
  deriving (Generic)

instance Pinchable SetValueResponse