Proposal: require spaces around the dot operator

Ben Millwood haskell at
Sun Feb 12 17:03:16 CET 2012

On Sun, Feb 12, 2012 at 3:51 PM, Ben Millwood <haskell at> wrote:
> On Sun, Feb 12, 2012 at 2:42 AM, Isaac Dupree
> <ml at> wrote:
>> On 02/11/2012 09:21 PM, Roman Leshchinskiy wrote:
>>> On 12/02/2012, at 02:04, Greg Weber wrote:
>>>> I am sorry that I made the huge mistake in referencing future possible
>>>> proposals. If this proposal passes, that has no bearing on whether the
>>>> other proposals would pass, it just makes them possible.
>>>> Please help me fix my error by stopping all discussions of future
>>>> proposals and focusing solely on the one at hand.
>>> But if we don't consider those future proposals, then what is the
>>> justification for this one? It does break existing code so there must be
>>> some fairly compelling arguments for it. I don't think it can be considered
>>> in isolation.
>> Does it help your concern about breaking existing code to make sure this
>> proposal has a LANGUAGE flag? ("-XDotSpaces" or such)
>> (I'm guessing that helps somewhat but not very satisfactorily; the more
>> default and standard it becomes, the more often it tends to break code
>> anyway.)
>> -Isaac
> Anything is allowed to happen if you have a LANGUAGE flag, but we're
> discussing what ought to be standardised.
> I think "existing code breaks" is not a great argument since we can
> just compile it with Haskell98 (or 2010) switches, although updating
> code is going to be a nuisance.
> [...]

On reflection I take this back, it would be a real nuisance to have to
do this. The rest of what I said stands independently of that, of

-1 to spaces around dot. I could be persuaded regarding spaces around
all operators: a quick survey of code I write suggests minimal changes
would be necessary. What about the comma, though? Spaces around that
would be pretty unnatural; it's already not /quite/ a real operator,
but I think that's a shame, and maybe it ought to be. So I'm not
voting on that proposal yet, although my instinct is I don't like it.

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