Unknown option -XPatternSig used in warning

Ian Lynagh igloo at earth.li
Wed Sep 19 21:39:03 EDT 2007


Hi Wolfram,

On Wed, Sep 19, 2007 at 01:45:00PM -0000, kahl at cas.mcmaster.ca wrote:
> 
> By the way, some of my LANGUAGE pragmas are getting quite long,
> and last time I tried I was not allowed to have a line break in there.

What version of GHC are you using? This works in 6.6:

    {-# LANGUAGE MultiParamTypeClasses,
                 OverlappingInstances #-}

    module Q where

    class Foo a b where
        foo :: a -> b

    instance Foo Int Bool
    instance Foo Int a

    x :: Int -> Bool
    x = foo

> Are there any plans to allow line breaks,
> or multiple LANGUAGE pragmas?

This also works:

    {-# LANGUAGE MultiParamTypeClasses #-}
    {-# LANGUAGE OverlappingInstances #-}

    module Q where

    class Foo a b where
        foo :: a -> b

    instance Foo Int Bool
    instance Foo Int a

    x :: Int -> Bool
    x = foo


Thanks
Ian



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