Proposal: Applicative => Monad: Is there any consensus?

Sittampalam, Ganesh ganesh.sittampalam at
Fri Feb 4 10:53:16 CET 2011

John Smith wrote:
> On 04/02/2011 09:50, Sittampalam, Ganesh wrote:
>> John Smith wrote:
>>> On 03/02/2011 16:42, Sittampalam, Ganesh wrote:
>>>>    (1) renaming fmap ->   map
>>>>    (2) adding join to Monad
>>>>    (3) removing (>>) from Monad
>>>>    (4) moving fail to MonadFail (this is a language change)
>>>>    (5) adding Applicative as a superclass of Monad
>>>>    .. and maybe anything else I missed
>>> This proposal (as in the patches attached to the ticket) is only
>>> (5). The wiki page is much broader than this.
>> The ticket is rather confusing, in that it says "The proposal is
>> detailed in  the wiki". I see the followup comment that the attached
>> patches "only implement the new Applicative =>  Monad hierarchy, but
>> do not change any names (as proposed on the wiki page)", but that
>> doesn't indicate the status of the other things one way or the other.
>> Also, the relevant attached patch seems to at least add join to
>> Monad:
>> na d_hierarchy.dpatch 
> Ticket descriptions are immutable, so I couldn't update it when the
> patch and wiki diverged. There is a section in the Wiki page
> dedicated to describing the proposed patch.  

OK, I see. Might be worth adding a note to that effect to the top of the
wiki page.

BTW I said when you first proposed this that I'm opposed until we have
language support that makes it easier to add new superclasses
non-disruptively, and that remains the case.


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