[Haskell-cafe] Monad of no `return` Proposal (MRP): Moving `return` out of `Monad`

[Bardur Arantsson]

On 10/06/2015 01:32 PM, Henrik Nilsson wrote:
> Dear all,
> 
[--snip--]
> 
> While we can discuss the extent of additional breakage
> MRP would cause, the fact remains it is a further
> breaking change. A survey of breakage to books as
> Herbert did is certainly valuable  (thanks!), but
> much breakage will (effectively) remain unquantifiable.
> 

This is an argument from FUD. If it's unquantifiable then it can (almost
by definition) neither count for nor against, can it?

> It is also clear from the discussions over the last
> couple of weeks, on the Haskell libraries list as well
> as various other forums and social media, that MRP is
> highly contentions.

Indeed.

> 
> This begs two questions:
> 
>   1. Is the Haskell Libraries list and informal voting process
>      really an appropriate, or even acceptable, way to adopt
>      such far-reaching changes to what effectively amounts to
>      Haskell itself?

I don't think that was ever the idea. (See other the other post by Erik.)

> 
>   2. Why the hurry to push MRP through?
> 

Personally, I don't think there's much need to push the actual
*breaking* change through, but I *do* think that deprecation warnings
should go in as quickly as possible.

[--snip--]
> 
> This brings us to question 2. Now that HaskellPrime is
> being resurrected, why the hurry to push MRP through?
> Surely HaskellPrime is the forum where breaking
> changes like MRP should be discussed, allowing as much
> time as is necessary and allowing for an as wide range
> of perspectives as possible to properly be taken into
> account?

Isn't that what we're trying to do on this very thread?

> 
> The need to "field test" MRP prior to discussing
> it in HaskellPrime has been mentioned. Graham and I
> are very sceptical. In the past, at least in the
> past leading up to Haskell 2010 or so, the community
> at large was not roped in as involuntary field testers.
> 

It seems to me that the community *is* being involved rather than being,
as you say, "involuntary field testers". (Again: see the very existence
of this thread).

Perhaps we should also be discussing what, exactly, is meant by
"community". It seems people have different ideas about that.

(For myself, I would certainly presume that being a member of the
community would include following along on at least a few mailing lists
or reddit or *somewhere* where all things Haskell get discussed.)

> If MRP is pushed through now, with a resurrection of
> HaskellPrime being imminent, Graham and I strongly believe
> that risks coming across to a very large part of the
> Haskell community as preempting proper process by facing
> the new HaskellPrime committee with (yet another) fait
> accompli.
> 
> Therefore, please let us defer further discussion and
> ultimate decision on MRP to the resurrected
> HaskellPrime committee, which is where it properly
> belongs. Otherwise, the Haskell community itself might
> be one of the things that MRP breaks.
> 

As I've certainly mentioned in this thread, the previous committee
didn't actually accomplish very much [1]. I also note that much of what
they *did* get through was actually mostly already field-tested in GHC
beforehand. (So there goes that argument, I guess.)

Regards,

[1] Though what they did accomplish is very much appreciated. Here's the
list linked from the Wiki page:
https://prime.haskell.org/query?state=accepted&milestone=Haskell+2010&order=priority