Unnecessary delete statement in function¶

ID: py/unnecessary-delete
Kind: problem
Security severity: 
Severity: warning
Precision: high
Tags:
   - maintainability
   - useless-code
Query suites:
   - python-security-and-quality.qls

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Passing a local variable to a del statement results in that variable being removed from the local namespace. When exiting a function all local variables are deleted, so it is unnecessary to explicitly delete variables in such cases.

Recommendation¶

Remove the del statement.

Example¶

In the function below, the variable x is assigned a value that is used for a calculation, and is then explicitly deleted before the function exits. In this case, the delete statement can be removed without changing the behavior of the function.

def unnecessary_delete():
    x = get_some_object()
    do_calculation(x)
    del x                       # This del statement is unnecessary

References¶

Python: The ‘del’ statement.
Python/C API Reference Manual: Reference counts.

GeezerVison

Unnecessary delete statement in function¶

Recommendation¶

Example¶

References¶