[Python-ideas] Fwd: Fwd: unpacking generalisations for list comprehension

[Chris Angelico]

On Sun, Oct 16, 2016 at 4:33 AM, אלעזר <elazarg at gmail.com> wrote:
> You are confusing here two distinct roles of the parenthesis: disambiguation
> as in "(1 + 2) * 2", and tuple construction as in (1, 2, 3). This overload
> is the reason that (1) is not a 1-tuple and we must write (1,).

Parentheses do not a tuple make. Commas do.

1, 2, 3, # three-element tuple
1, 2, # two-element tuple
1, # one-element tuple

The only time that a tuple requires parens is when it's the empty tuple, ().

ChrisA