Re: [Haskell-cafe] [] == []

On Tue, Mar 10, 2015 at 2:03 PM, Brandon Allbery wrote:

On Mon, Mar 9, 2015 at 10:33 PM, Rustom Mody wrote:

...

My impression is that earlier [] == [] used to give a type error. Now it gives True.

So 1. Which instance of == is being used? 2. Is there some option controlling this behavior?

The instance being used is (), and it's controlled by -XExtendedDefaultRules.

https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/interactive-...

Thats what I first thought Tried starting ghci with -XNoExtendedDefaultRules but it does not turn it off