On Wed, May 8, 2019 at 4:31 AM Eli the Bearded <*@eli.users.panix.com> wrote: > > In comp.lang.python, Paul Rubin <no.email@nospam.invalid> wrote: > > Thanks for posting this. I'm learning python and am very familiar with > this "game". > > > #!/usr/bin/python3 > > from itertools import chain > > > > def adjacents(cell): # generate coordinates of cell neighbors > > x, y = cell # a cell is just an x,y coordinate pair > > return ((x+i,y+j) for i in [-1,0,1] for j in [-1,0,1] if i or j) > > This line confuses me. How do you expect "if i or j" to work there?
It means that if either i or j has a non-zero value, this will yield something. With three possible values for i and three for j, it would normally create nine results; but that condition means it will create eight, skipping the (0, 0) option. Since the function is meant to give you all the neighbors of a cell, it makes sense that it shouldn't return the cell itself. ChrisA -- https://mail.python.org/mailman/listinfo/python-list
