Given a class Foo:

> class Foo f where

>     bar :: f -> Bool

>     baz :: f -> Char -> Int

does the record type Foo'

>  data Foo' = Foo' {

>      bar' :: Bool,

>      baz' :: Char -> Int

>      }

>  

>  instance Foo Foo' where

>      bar = bar'

>      baz = baz'

where the fields of the record Foo' are just implementations of the functions of Foo have any special name?

In some sense it's a canonical instance of Foo; we could trivially write a universal

> toFoo' :: Foo f => f -> Foo'

function.

I ran across this pattern and wondered whether it was useful enough to have received a name.  It vaguely resembles a typeclass dictionary or a vtable in an OOP language.

--Eric