Hi, On 2015-11-27 at 10:29:09 +0100, Akio Takano wrote: [...]
Thank you for the information. If I understand correctly, this -fwarn-noncanonical-monad-instances warning doesn't address my concern, because it won't warn about a monad that defines neither (>>) nor (*>) explicitly, which I expect to be a common case.
You're right, from what I've seen the majority of Monad instances don't bother to override (>>)/(*>) currently. But do we really want every Applicative/Monad to explicitly define (*>) (and consequently (>>)=(*>)) ? If so, it seems to be unfortunate that we have an overridable default implementation for (*>)/(>>) in place, as that IMO suggests that you're only supposed to override (*>) in those less common cases where it provides a benefit over the default implementation. What's the point of the default implementation otherwise? -- hvr