Elegant and cheap way to transform lists in python -


suppose have list of numbers i'd increment , i'm interested in incremented values, not original ones afterwards. pythonic way in situ, without copying list?

does

a = [1, 2, 3] = [i+1 in a]

result in intermediate copy of a, or python interpreter optimize this?

unfortunately, python knowledge still superficial. mother tongue c++.

without copying list can this:

in [1]: = [1, 2, 3]  in [2]: id(a) out[2]: 48701592  in [3]: in xrange(len(a)): # range(len(a)) python 3    ...:     a[i] += 1    ...:       in [4]: out[4]: [2, 3, 4]  in [5]: id(a) out[5]: 48701592

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