On Fri, Nov 5, 2021 at 6:23 AM <2qdxy4rzwzuui...@potatochowder.com> wrote: > > On 2021-11-04 at 14:36:48 -0400, > David Lowry-Duda <da...@lowryduda.com> wrote: > > > > x_increment, y_increment = (scale * i for i in srcpages.xobj_box[2:]) > > > > > > (scale * i for i in srcpages.xobj_box[2:]) is a generator, a single > > > object, it should not be possible to unpack it into 2 variables. > > > > If you know the exact number of values in the generator, you can do > > this. Here is an oversimplified example. > > > > l = [0, 1, 2, 3, 4, 5] > > a, b = (elem * 10 for elem in l[:4]) > > print(a, b) # prints 40 50 > > > > This is very fragile code and I would recommend against using it. > > How is that any more fragile than any other operation that destructs (or > doesn't) a tuple? >
The only part that's fragile, in my opinion, is (from the initial post) that it's using removal syntax to slice off some, which is fragile against the original input length: x_increment, y_increment = (scale * i for i in srcpages.xobj_box[2:]) But since it says "box", I would start by assuming that it has four elements. (They might be x1,y1,x2,y2 or x,y,w,h but it'll almost always be four.) So it's not TOO fragile, when working with boxes, but it is a little less clear that thing[2:] will always give exactly two results. ChrisA -- https://mail.python.org/mailman/listinfo/python-list
