List mutation method gotcha - How well known?
Diez B. Roggisch
deets at nospam.web.de
Thu Mar 13 11:21:52 CET 2008
Hendrik van Rooyen wrote:
> I am surprised that it took me so long to bloody my nose on this one.
> It must be well known - and I would like to find out how well known.
> So here is a CLOSED BOOK multiple choice question - no RTFM,
> no playing at the interactive prompt:
> Given the following three lines of code at the interactive prompt:
> foo = [1,2,3,4]
> x = foo.append(5)
> print x
> What will be the output (choose one):
> 1) [1,2,3,4]
> 2) [1,2,3,4,5]
> 3) That famous picture of Albert Einstein sticking out his tongue
> 4) Nothing - no output
> 5) None of the above
> I undertake to summarise answers posted to complete this "survey".
None, as python chose deliberately to return None on mutating functions like
append, sort and reverse.
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