When I assign a list to variable why Pycharm give me a prompt that is "this list creation could be rewritten as a list literal"?

python list pycharm
russell picture russell · Jun 26, 2015 · Viewed 50.5k times · Source

I am a Python beginner and have a puzzle. When I write code like this:

lst = [1, 2, 3, 4]

Pycharm give me a prompt that is "this list creation could be rewritten as a list literal". But if it's replaced by

lst = list([1, 2, 3, 4])

Pycharm doesn't say anything. Who could tell me why?

Is this code like lst = [1, 2, 3, 4] legal in Python? Can I ignore prompt?

Answer

Shawn picture Shawn · Feb 4, 2016

It's totally legal to write code like that in Python. However, writing code like

lst = [1, 2, 3, 4, 12]

would be "better" than

lst = [1, 2, 3, 4]
... # code has nothing do to with lst
lst.append(12)

In general, the former one would have better performance than the latter one, but if the latter one is more readable in your case/you have a good reason doing that, then you can ignore the PyCharm prompt.

If it bothers you, you can turn this inspection off in

"PyCharm->settings->editor->inspection->Python->List creation could be..."

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