Hi,
Am Montag, den 01.11.2010, 22:28 +0000 schrieb Andrew Coppin:
> The other day, I accidentally came up with this:
>
> {-# LANGUAGE RankNTypes #-}
>
> type Either x y = forall r. (x -> r) -> (y -> r) -> r
>
> left :: x -> Either x y
> left x f g = f x
>
> right :: y -> Either x y
> right y f g = g y
>
> This is one example; it seems that just about any algebraic type can
> be encoded this way. I presume that somebody else has thought of this
> before. Does it have a name?that reminds me very much of a similar sounding mail to this list by me¹. Is there a name for this meme already? :-) Greetings, Joachim ¹ http://www.mail-archive.com/haskell-cafe@haskell.org/msg21500.html -- Joachim Breitner e-Mail: m...@joachim-breitner.de Homepage: http://www.joachim-breitner.de ICQ#: 74513189 Jabber-ID: nome...@joachim-breitner.de
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