Unused variables are variables that are assigned but never read. Such assignments are unnecessary and don’t contribute to the functionality or
clarity of the code. They may even negatively impact performance. Removing them enhances code cleanliness and readability. Even if the unnecessary
operations do not do any harm in terms of the program’s correctness, they are - at best - a waste of computing resources.
Exceptions
This rule ignores initializations to -1, 0, 1, nil, true, false and
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