On 05/08/2015 08:53, John Doe wrote:
To pass by reference or by copy of - that is the question from hamlet.
("hamlet" - a community of people smaller than a village python3.4-linux64)
xlist = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
i = 0
for x in xlist:
print(xlist)
print("\txlist[%d] = %d" % (i, x))
if x%2 == 0 :
xlist.remove(x)
print(xlist, "\n\n")
i = i + 1
So, catch the output and help, PLEASE, me improve the answer:
Does it appropriate ALWAYS reevaluate the terms of the list on each
iteration?
But if I want to pass a copy to FOR instead of a reference (as seen from
an output) and reduce unreasonable reevaluation, what I must to do for
that?
From https://docs.python.org/3/tutorial/introduction.html#lists, but
chopped around a little:-
<quote>
All slice operations return a new list containing the requested
elements. This means that the following slice returns a new (shallow)
copy of the list:
>>> squares = [1, 4, 9, 16, 25]
>>> squares[:]
[1, 4, 9, 16, 25]
</quote>
Hence:-
for x in xlist[:]:
etc.
--
My fellow Pythonistas, ask not what our language can do for you, ask
what you can do for our language.
Mark Lawrence
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