Pylint warning: Possible unbalanced tuple unpacking with sequence

python tuples pylint packing
user1659464 picture user1659464 · Jan 16, 2015 · Viewed 8.2k times · Source

I have a piece of Python code:

def func1():                                                                                                                  
    a=set()
    b = ','.join(map(str, list(a)))
    return  b, []

def func2():
    d = 1
    e = 2
    return func1() + (d, e,)

def main():
    a,b,c,d = func2()

if __name__ == '__main__':
    main()

When I run it through pylint (1.4.0), I receive the warning: 

W: 12, 4: Possible unbalanced tuple unpacking with sequence: left side has 4 label(s), right side has 3 value(s) (unbalanced-tuple-unpacking)

It seems that func2 will always return four results. What does the error mean and why?

Answer

The Chess Guy 20 picture The Chess Guy 20 · Feb 28, 2019

If the warning is erroneous, it can be disabled by appending # pylint: disable=unbalanced-tuple-unpacking to the line.

Related questions

Convert list to tuple in Python

I'm trying to convert a list to a tuple. Most solutions on Google offer the following code: l = [4,5,6] tuple(l) However, the code results in an error message when I run it: TypeError: 'tuple' object is not callable How can …

Read More
How to sort a list/tuple of lists/tuples by the element at a given index?

I have some data either in a list of lists or a list of tuples, like this: data = [[1,2,3], [4,5,6], [7,8,9]] data = [(1,2,3), (4,5,6), (7,8,9)] And I want to sort by the 2nd element in the subset. Meaning, sorting by 2,5,8 where 2 is from (1,2,3), 5 is from (4,5,6). What …

Read More
Convert tuple to list and back

I'm currently working on a map editor for a game in pygame, using tile maps. The level is built up out of blocks in the following structure (though much larger): level1 = ( (1,1,1,1,1,1) (1,0,0,0,0,1) (1,0,0,0,0,1) (1,0,0,0,0,1) (1,0,0,0,0,1) (1,1,1,1,1,1)) where "1" is a block that's a wall and "0" is …

Read More