What's the difference between list() and [] [duplicate]

Question

What's the difference between the following code:

foo = list() 

And

foo = [] 

Python suggests that there is one way of doing things but at times there seems to be more than one.

Answer 1

For the sake of completion, another thing to note is that list((a,b,c)) will return [a,b,c], whereas [(a,b,c)] will not unpack the tuple. This can be useful when you want to convert a tuple to a list. The reverse works too, tuple([a,b,c]) returns (a,b,c).

Edit: As orlp mentions, this works for any iterable, not just tuples.

Answer 2

One's a function call, and one's a literal:

>>> import dis >>> def f1(): return list() ...  >>> def f2(): return [] ...  >>> dis.dis(f1)   1           0 LOAD_GLOBAL              0 (list)               3 CALL_FUNCTION            0               6 RETURN_VALUE         >>> dis.dis(f2)   1           0 BUILD_LIST               0               3 RETURN_VALUE         

Use the second form. It's more Pythonic, and it's probably faster (since it doesn't involve loading and calling a separate funciton).