“Redeclared s defined above without usage”

Question

for i in range(10):
    s = 5
    for j in range(10):
        s = min(s)

The above code gives the title of this question as warning in IntelliJ for the

Answer 1

Your hypothesis is nearly correct. The name s was bounded to an integer whose value was never used nor changed in the enclosing loop and yet it is rebounded to another value (although that will raise an error) in the nested loop. Note that the first assignment does not change with any iteration of the outer for loop.

The IDE's warning suggests the first assignment inside the loop is unnecessary as s was never changed. The assignment might as well have been better placed outside the for loop which will prevent a redundant binding and rebinding:

s = 5
for i in range(10):
    ...