On 12/07, Ivan Evstegneev wrote: > Hello, > > When I have worked in Python shell (IDLE) I found this issue: > > >>>x = ([1, 2], [3, 4], [5, 6]) > >>>L = [] > >>>for I in x: > L.extend(i) > > >>>L > [1,2,3,4,5,6] > > But when I try to make comprehension using above expression, I get this: > > >>>x = ([1, 2], [3, 4], [5, 6]) > >>>L = [] > >>> [L.extend(i) for i in x] > [None, None, None]
Yes. per the doc, list.extend() returns None. > > But this works fine within function: > > >>> def myfunc(): > x = ([1, 2], [3, 4], [5, 6]) > L = [] > [L.extend(i) for i in x] > print(L) > > >>>myfunc() > [1, 2, 3, 4, 5, 6] This is also so true, as you are print the var 'L'. > > The question is why I'm getting empty list while working with comprehension > in interactive console? You are also getting [None]*3 in comprenhension inside a function. -- Shiyao Ma http://introo.me -- https://mail.python.org/mailman/listinfo/python-list
