Re: Proposal: Add conspicuously missing Functor instances for tuples

I can sympathize with your sentiment. Normally, if there's a datatype whose instance I don't want to use, I just make my own replacement. However, it's hard to do that with tuples given their special syntactic treatment. It might be worth looking into adding RebindableSyntax for tuples [1] to address scenarios like this. Ryan S. ----- [1] https://ghc.haskell.org/trac/ghc/ticket/7845 On Mon, Jan 18, 2016 at 4:22 PM, Henning Thielemann wrote:

On Mon, 18 Jan 2016, John Wiegley wrote:

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> Henning Thielemann writes:

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I would never use such an instance. Can I be warned if I accidentally use it anyway?

I don't know why "I wouldn't use it" should extend to "it shouldn't exist".

Because I cannot turn it off and I cannot get warning. It is inserted by GHC whenever it matches, even if I made a mistake when programming.