Hello, {-# LANGUAGE OverlappingInstances, FlexibleInstances #-} import Data.Binary
instance Binary [String] where get = undefined put = undefined works fine here on GHC 6.12.3. That being said, it would be safer perhaps to add a newtype around [String] so you can avoid the orphan instance as well, i.e. import Data.Binary newtype MyType = MyType [String] instance Binary MyType where get = undefined put = undefined Cheers, Jasper On Wed, Jan 5, 2011 at 9:24 AM, Magicloud Magiclouds <magicloud.magiclo...@gmail.com> wrote: > Hi, > I am using Data.Binary which defined "instance Binary a => Binary > [a]". Now I need to define "instance Binary [String]" to make > something special for string list. > How to make it work? I looked into the chapter of > overlappinginstances, nothing works. > -- > 竹密岂妨流水过 > 山高哪阻野云飞 > > _______________________________________________ > Haskell-Cafe mailing list > Haskell-Cafe@haskell.org > http://www.haskell.org/mailman/listinfo/haskell-cafe > _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe