Proposal: require spaces around the dot operator

John Meacham john at
Fri Feb 10 03:40:02 CET 2012

There is also '~' which has no use in expressions right now.

I am still undecided on the utility of TLDR, bogarting already contested
syntax seems premature.

I question the value of looking too much like other languages, in some sense
it hurts us, new programmers are constantly trying to define classes
first thing because they have the same name as a somewhat related thing
from whatever language they are coming from.
Even though they are rarely the correct solution for anything you would
encounter in basic haskels programming.
I don't know whether using '.' will exacerbate this or not, but it is far from
clear that it is a good thing.


On Thu, Feb 9, 2012 at 6:27 PM, Daniel Peebles <pumpkingod at> wrote:
> I'm very happy to see all the work you're putting into the record
> discussion, but I'm struggling to see why people are fighting so hard to get
> the dot character in particular for field access. It seems like a huge
> amount of work and discussion for a tiny bit of syntactic convenience that
> we've only come to expect because of exposure to other very different
> languages.
> Is there some fundamental reason we couldn't settle for something like # (a
> valid operator, but we've already shown we're willing to throw that away in
> the MagicHash extension) or @ (only allowed in patterns for now)? Or we
> could even keep (#) as a valid operator and just have it mean category/lens
> composition.
> Thanks,
> Dan
> On Thu, Feb 9, 2012 at 9:11 PM, Greg Weber <greg at> wrote:
>> Similar to proposal #20, which wants to remove it, but immediately
>> less drastic, even though the long-term goal is the same.
>> This helps clear the way for the usage of the unspaced dot as a record
>> field selector as shown in proposal #129.
>> After this proposal shows clear signs of moving forward I will add a
>> proposal to support a unicode dot for function composition.
>> After that we can all have a lively discussion about how to fully
>> replace the ascii dot with an ascii alternative such as <~ or <<<
>> After that we can make the dot operator illegal by default.
>> This has already been discussed as part of a records solution on the
>> ghc-users mail list and documented here:
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