bare-except / W0702

Message emitted:

No exception type(s) specified

Description:

A bare ``except:`` clause will catch ``SystemExit`` and ``KeyboardInterrupt`` exceptions, making it harder to interrupt a program with ``Control-C``, and can disguise other problems. If you want to catch all exceptions that signal program errors, use ``except Exception:`` (bare except is equivalent to ``except BaseException:``).

Problematic code:

try:
    import platform_specific_module
except:  # [bare-except]
    platform_specific_module = None

Correct code:

try:
    import platform_specific_module
except ImportError:
    platform_specific_module = None

Additional details:

A good rule of thumb is to limit use of bare ‘except’ clauses to two cases: - If the exception handler will be printing out or logging the traceback; at least the user will be aware that an error has occurred. - If the code needs to do some cleanup work, but then lets the exception propagate upwards with raise. try...finally can be a better way to handle this case.

Related links:

• Programming recommendation in PEP8

• PEP 760 – No More Bare Excepts (Rejected)

• Discussion about PEP 760

Created by the exceptions checker.