"Data blocks" syntax specification draft

[Ian Kelly]

On Wed, May 23, 2018 at 12:49 AM, Steven D'Aprano
<steve+comp.lang.python at pearwood.info> wrote:
> On Tue, 22 May 2018 09:43:55 -0600, Ian Kelly wrote:
>
>> In other words, the rule is not really as simple as "commas make
>> tuples". I stand by what I wrote.
>
> Being pedantic is great, but if you're going to be pedantic, it pays to
> be *absolutely correctly* pedantic *wink*
>
> Chris is right to say "commas make tuples", and never implied that making
> tuples is *all* that commas do. That would be an absurd thing for him to
> say. Fortunately he didn't :-)
>
> If your comment had been posed as an addition to Chris' comment ("By the
> by, commas also do this that and the other...") then it would have been
> unobjectionable. But by posing it as a correction ("Although, if the rule
> were really as simple ...") you left yourself wide-open to be criticised
> in turn for failing to be pedantic *enough*.

I don't understand why you read that as a correction and not as an
addition. I never said that Chris was *wrong*. I read my comment as
implying that he was correct, and also that there was more to it.
Maybe you are the one who is being overly pedantic.

> Of course commas can be used elsewhere, just as the use of "if" in if
> statements doesn't prevent us from using that same token in the ternary
> if operator.
>
> In the context of the discussion (namely, the mistaken belief that tuples
> are created by parentheses, which we can often leave out) pointing out
> that commas are *also* used as separators in import statements, lists,
> dicts, function parameter lists etc adds noise but no insight to the
> understanding of tuples.

Then you misunderstood my post. My point was not that commas are also
used for other purposes, but that there are other special cases beyond
the empty tuple where commas alone are insufficient and parentheses
are required to create a tuple.