CODEWITHSUNDEEP
pythonpython-3.x
kmiklas
kmiklas

Reputation: 13433

Is multiple array initialization on the same line the same as on separate lines?

In Python 3.x, can arrays be initialized on the same line?

I'm trying to be a "one-liner guy," but not certain of the subtleties between these two.

Minimal, complete, verifiable example:

Are these statements equivalent?

A:

def main():
    a = b = []

B:

def main():
    a = []
    b = []

Upvotes: 1

Views: 113

Answers (1)

kaya3
kaya3

Reputation: 51037

These two are not equivalent; the first one creates two references to the same list:

>>> a = b = []
>>> a.append(1)
>>> b
[1]

The second creates two lists:

>>> a = []
>>> b = []
>>> a.append(1)
>>> b
[]

To create two lists on one line, you can do a parallel assignment:

>>> a, b = [], []
>>> a.append(1)
>>> b
[]

Upvotes: 4

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