[Python-Dev] A grammatical oddity: trailing commas in argument lists -- continuation

Terry Reedy tjreedy at udel.edu
Mon Dec 13 22:21:20 CET 2010

On 12/13/2010 2:17 PM, Antoine Pitrou wrote:
> On Mon, 13 Dec 2010 14:09:02 -0500
> Alexander Belopolsky<alexander.belopolsky at gmail.com>  wrote:
>> On Mon, Dec 13, 2010 at 11:54 AM, Guido van Rossum<guido at python.org>  wrote:
>>> I'm at least +0 on
>>> allowing trailing commas in the situation the OP mentioned.
>> FWIW, I am also about +0.5 on allowing trailing comma.  Note that in a
>> similar situation,  the C standardization committee has erred on the
>> side of consistency:
>> """
>> A new feature of C99: a common extension in many implementations
>> allows a trailing comma after the list of enumeration constants. The
>> Committee decided to adopt this feature as an innocuous extension that
>> mirrors the trailing commas allowed in initializers.
>> """ http://www.open-std.org/jtc1/sc22/wg14/www/C99RationaleV5.10.pdf
>> Similarly, I find allowing trailing comma in keyword only arguments
>> lists to be an innocuous extension that mirrors the trailing commas
>> allowed in the positional arguments lists.
> +1 from me as well. Special cases are hard to remember.

Same here. A strong +1 for a consistent rule (always or never allowed) 
with a +1 for always given others use case of one param/arg per line.

So I think the issues should be reopened.

Terry Jan Reedy

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