Proposal to solve the `EitherT` problem.

Bardur Arantsson spam at
Wed Aug 14 19:01:54 CEST 2013

On 2013-08-14 17:43, Gabriel Gonzalez wrote:
> I echo Edward's sentiments.  If you disagree with Edward's design
> choices then you should vote with your code instead of your +1's by
> building and actively maintaining libraries that uphold your design
> principles.
> I see all these hypothetical arguments that `Either` might cause
> somebody to accidentally use its monad instance once, ever, but let's
> consult the facts:
> * Nobody here has even lifted a finger to write up a library with this
> hypothetical alternative to the `Either` without the `Monad` instance. 
> This signals to me that the people arguing for removing the `Monad`
> instance don't actually care about this as much about this as they say
> they do.
> * Nobody has ever come onto Haskell cafe, Stack Overflow, or /r/haskell
> and asked: "Where can I find an `Either` without the `Monad` instance?" 
> This signals to me that most Haskell programmers don't actually want
> this "feature" as much as you say they do.
> * Lots of Haskell programmers use Either and EitherT fluently for error
> handling without any confusion or programming mistakes.  My `errors`
> library is proof of that:
> The reason Edward's libraries are popular and so widely used is because
> they solve an *actual* need, not a hypothetical need.

+1 all the way.

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