RE: Type family constraints

I’m afraid I don’t understand the question. type instance XIPBinds (GhcPass 'Parsed) = NoExt type instance XIPBinds (GhcPass 'Renamed) = NoExt type instance XIPBinds (GhcPass 'Typechecked) = TcEvBinds it works fine for type instance XIPBinds (GhcPass _) = NoExt You

Re: Type family constraints

Thanks Richard Ryan Scott has also put together a solution[1], which is basically what you proposed. But in terms of trying to clean up the code by removing a straightforward constraint type, I think this solution adds more complexity than it removes. So I will leave it as it is. Alan [1]

Re: Type family constraints

> On Apr 23, 2018, at 6:56 AM, Alan & Kim Zimmerman wrote: > > Is there any way to express that `pass` must be valid for each value of > `Pass` in the following instance head? > No, there isn't. And for good reason: whatever you're trying to do likely requires some