He was referring to Haskell's syntax for derived instances - http://www.haskell.org/tutorial/stdclasses.html#sect8.4 http://www.haskell.org/tutorial/stdclasses.

He was referring to Haskell's syntax for derived instances - http://www.haskell.org/tutorial/stdclasses.html#sect8.4 http://www.haskell.org/tutorial/stdclasses.html#sect8.4