[Python-ideas] Another attempt at a sum() alternative: the concatenation protocol

[Masklinn]

On 16 juil. 2013, at 14:25, Oscar Benjamin <oscar.j.benjamin at gmail.com> wrote:
> On 16 July 2013 13:28, Joshua Landau <joshua at landau.ws> wrote:
>> On 16 July 2013 11:21, Oscar Benjamin <oscar.j.benjamin at gmail.com> wrote:
>>> On 16 July 2013 07:50, Nick Coghlan <ncoghlan at gmail.com> wrote:
>>> 
>>> If people are using sum() to concatenate lists then this should be
>>> taken not as evidence that a new solution needs to be found but as
>>> evidence that chain is not sufficiently well-known. The obvious
>>> solution to that is not to implement a new protocol but to make the
>>> existing solution more well known i.e. move chain.from_iterable to
>>> builtins and rename it (the obvious choice being concat).
>> 
>> You could wait for PEP 448, which will let you use [*sublist for
>> sublist in list_to_be_flattened].
> 
> Well that does look good. How exactly does it unroll? Does the *
> translate as yield from but without the weird comprehension turning
> into a generator function behaviour?

For a listcomp, surely it translates into a .extend of the accumulator?