List syntax (was: Re: help from the community?)

Kirsten Chevalier catamorphism at
Fri Feb 2 12:47:52 EST 2007

On 2/2/07, Douglas Philips <dgou at> wrote:
> Hmmm...stated another way:
> I am proposing that the list and tuple syntax change to be consistent
> with the import and export syntax.
> The argument that a trailing comma "means" "the programmer forgot the
> last item" in a list / tuple is
> inconsistent with the deliberately explicit permissiveness of a
> trailing comma in the import / export lists.
> In the import / export lists such a trailing comma does not mean
> "programmer forgot additional thing at the end."

Ok, now I see your point. I agree it does seem inconsistent. I don't
know the reasons for the choice to make the import/export lists work
that way, but I would guess that it's because when people use
import/export lists, they often add/remove items from the lists, and
allowing the trailing comma just makes things easier. On the other
hand, with constant lists and tuples, you're probably not going to
frequently edit the same constant list value. Am I missing something?


Kirsten Chevalier* chevalier at *Often in error, never in doubt
"The world is absurd and beautiful and small" -- Ani DiFranco

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