Append returning None

Asked Oct 22 '16 at 12:26

Active Oct 22 '16 at 12:43

Viewed 45 times

Was having trouble figuring out why self.Curr returns None. I now learned that append edits a list and returns None. However, my goal was for PrevList / prev to remain unchanged and have self.Curr be the new appended list. Can anyone explain what is going on and suggest how I can assign self.Curr to the new appended list while keeping PrevList / prev unchanged?

class AssignmentNode:
    def __init__(self,asmt,prev):
        self.Asmt = asmt
        self.PrevList = prev

        self.Curr = prev.append(asmt)

AssignmentNode("A",[])

I even tried...

c = prev.append(asmt)
self.Curr = c

...but that did not work either.

asked Oct 22 '16 at 12:26

NoPayn

1

Either `self.Curr = prev + [asmt]` or `c = prev.copy()` followed by `c.append(asmt)` and `self.Curr = c` – Julien Oct 22 '16 at 12:29
By the way, @JulienBernu - I use PhraseExpress to easily reproduce canned posts. You can also use something like AutoHotkey or other macro/text expander languages/programs. – TigerhawkT3 Oct 22 '16 at 12:34
1

@TigerhawkT3: found a better one. – Martijn Pieters Oct 22 '16 at 12:44
@MartijnPieters - That certainly is a better one. :) – TigerhawkT3 Oct 22 '16 at 12:44

Append returning None

0 Answers0