[racket-dev] [plt] Push #21108: master branch updated

On Fri, Sep 17, 2010 at 11:52 AM, Robby Findler
<robby at eecs.northwestern.edu> wrote:
> On Fri, Sep 17, 2010 at 11:50 AM, Casey Klein
> <clklein at eecs.northwestern.edu> wrote:
>> On Fri, Sep 17, 2010 at 11:39 AM,  <robby at racket-lang.org> wrote:
>>> robby has updated `master' from c6fc7137ee to ce211ac364.
>>>  http://git.racket-lang.org/plt/c6fc7137ee..ce211ac364
>>>
>>> =====[ 1 Commits ]======================================================
>>>
>>> Directory summary:
>>>  10.1% collects/redex/private/
>>>  83.2% collects/redex/tests/bmps-macosx/
>>>   6.6% collects/redex/tests/
>>>
>>> ~~~~~~~~~~
>>>
>>> ce211ac Robby Findler <robby at racket-lang.org> 2010-09-17 11:39
>>> :
>>> | adjusted metafunction application rendering so that ellipses do not
>>> | get commas put in front of them
>>> :
>>
>> FWIW, if I were typesetting this example by hand, I would have done it
>> the old way
>>
>>   rdups[| x_1, x_2, ..., x_1, x_3, ... |]
>>
>> not the new way
>>
>>   rdups[| x_1, x_2 ..., x_1, x_3 ... |]
>>
>> but maybe I'm alone in that preference.
>
> I had thought that for a while, but some examples I'm working with
> today get really confusing when you do that and just seem ugly. The
> ellipses really isn't a separate item in the argument list; it is an
> operator on the thing that comes before and the lack of a paren
> emphasizes this properly.
>
> IMO.
>

In that case, maybe there should be a parameter? (I'll be the one to
add it if you want.)

This rendering seems like a departure from convention. The first two
books I pulled off my shelf (_Semantics of Programming Languages_ and
_Invitation to Discrete Mathematics_) do it the old way.