On Thu, Aug 10, 2017 at 7:28 AM, Steve D'Aprano <steve+pyt...@pearwood.info> wrote:
> Every few years, the following syntax comes up for discussion, with some > people > saying it isn't obvious what it would do, and others disagreeing and saying > that it is obvious. So I thought I'd do an informal survey. > > What would you expect this syntax to return? > > [x + 1 for x in (0, 1, 2, 999, 3, 4) while x < 5] > >>> [1, 2, 3, 4] > > > For comparison, what would you expect this to return? (Without actually > trying > it, thank you.) > > [x + 1 for x in (0, 1, 2, 999, 3, 4) if x < 5] > > >>> [1, 2, 3, 4, 5] > > How about these? > > [x + y for x in (0, 1, 2, 999, 3, 4) while x < 5 for y in (100, 200)] > I'd expect this to throw a syntax error. > > [x + y for x in (0, 1, 2, 999, 3, 4) if x < 5 for y in (100, 200)] > Syntax error again. > > > > Thanks for your comments! > > > > -- > Steve > “Cheer up,” they said, “things could be worse.” So I cheered up, and sure > enough, things got worse. > > -- > https://mail.python.org/mailman/listinfo/python-list > -- https://mail.python.org/mailman/listinfo/python-list
