MiddleDebuggingOccasional

Why is this `ValueError` handler unreachable?

The second handler never runs, even when risky raises a ValueError.

Python

try:
    risky()
except Exception:
    handle_generic()
except ValueError:
    handle_value_error()

Find and fix the bug.

except Exception is checked first and catches ValueError too (it is a subclass), so the ValueError handler is unreachable (Python even flags it). Put specific exceptions before general ones. Also avoid a bare except: — it swallows KeyboardInterrupt / SystemExit.

Writing the general handler before the specific one
Thinking Python picks the most specific matching handler regardless of order
Believing ValueError is not a subclass of Exception

What does Python warn about for an unreachable except clause?
Why is a bare except: discouraged even when ordering is correct?

Back to questions Open topic in roadmap →Answer it yourself — Quiz

Back to questions

MiddleDebuggingOccasional

Why is this `ValueError` handler unreachable?

The second handler never runs, even when risky raises a ValueError.

Python

try:
    risky()
except Exception:
    handle_generic()
except ValueError:
    handle_value_error()

Find and fix the bug.

Writing the general handler before the specific one
Thinking Python picks the most specific matching handler regardless of order
Believing ValueError is not a subclass of Exception

What does Python warn about for an unreachable except clause?
Why is a bare except: discouraged even when ordering is correct?

Back to questions Open topic in roadmap →Answer it yourself — Quiz

Why is this ValueError handler unreachable?

Why is this ValueError handler unreachable?

Why is this `ValueError` handler unreachable?

Why is this `ValueError` handler unreachable?