Ahem. What I should have said is that the list of alternatives always covers all cases that can occur. For example in data Foo = Red | Green | Blue ...case x of Red -> True other -> ...(case x of Green -> ... Blue -> ... ) ... The inner case is considered exhaustive because Red can't occur. Any Red alternative in the inner case will be considered dead, and removed. Simon | -----Original Message----- | From: glasgow-haskell-users-admin@haskell.org [mailto:glasgow-haskell-users-admin@haskell.org] | On Behalf Of David Sabel | Sent: 28 July 2003 21:43 | To: glasgow-haskell-users@haskell.org | Subject: Re: case-identity | | > In Core, the list of alternatives is always exhaustive. | | Ok, thanks. | So I assume the "dead alternative elimination" is no longer done in | the simplifier? | | ( | The dead alternative elimination is defined as: | | case x of ===> case x of | P1 -> E1 P1 -> E1 | ... ... | ci a1 ... an -> Ei Pn -> En | ... [without ci a1 ... an -> Ei] | Pn -> En | | if x is not of constructor c_i | ) | | David | | _______________________________________________ | Glasgow-haskell-users mailing list | Glasgow-haskell-users@haskell.org | http://www.haskell.org/mailman/listinfo/glasgow-haskell-users