From 446463f8dbce0556be8020914f37089b63bb8ab6 Mon Sep 17 00:00:00 2001 From: Julien Palard Date: Thu, 6 Feb 2020 23:16:48 +0100 Subject: bpo-39534: Doc: Clarify return in finally (GH-18324) --- Doc/tutorial/errors.rst | 36 +++++++++++++++++++++++++++--------- 1 file changed, 27 insertions(+), 9 deletions(-) diff --git a/Doc/tutorial/errors.rst b/Doc/tutorial/errors.rst index 8f86eca..ab23df9 100644 --- a/Doc/tutorial/errors.rst +++ b/Doc/tutorial/errors.rst @@ -388,15 +388,33 @@ example:: File "", line 2, in KeyboardInterrupt -If a :keyword:`finally` clause is present, the :keyword:`finally` clause will execute as the last task before the :keyword:`try` statement completes. The :keyword:`finally` clause runs whether or not the :keyword:`try` statement produces an exception. The following points discuss more complex cases when an exception occurs: - -* If an exception occurs during execution of the :keyword:`!try` clause, the exception may be handled by an :keyword:`except` clause. If the exception is not handled by an :keyword:`except` clause, the exception is re-raised after the :keyword:`!finally` clause has been executed. - -* An exception could occur during execution of an :keyword:`!except` or :keyword:`!else` clause. Again, the exception is re-raised after the :keyword:`!finally` clause has been executed. - -* If the :keyword:`!try` statement reaches a :keyword:`break`, :keyword:`continue` or :keyword:`return` statement, the :keyword:`finally` clause will execute just prior to the :keyword:`break`, :keyword:`continue` or :keyword:`return` statement's execution. - -* If a :keyword:`finally` clause includes a :keyword:`return` statement, the :keyword:`finally` clause's :keyword:`return` statement will execute before, and instead of, the :keyword:`return` statement in a :keyword:`try` clause. +If a :keyword:`finally` clause is present, the :keyword:`!finally` +clause will execute as the last task before the :keyword:`try` +statement completes. The :keyword:`!finally` clause runs whether or +not the :keyword:`!try` statement produces an exception. The following +points discuss more complex cases when an exception occurs: + +* If an exception occurs during execution of the :keyword:`!try` + clause, the exception may be handled by an :keyword:`except` + clause. If the exception is not handled by an :keyword:`!except` + clause, the exception is re-raised after the :keyword:`!finally` + clause has been executed. + +* An exception could occur during execution of an :keyword:`!except` + or :keyword:`!else` clause. Again, the exception is re-raised after + the :keyword:`!finally` clause has been executed. + +* If the :keyword:`!try` statement reaches a :keyword:`break`, + :keyword:`continue` or :keyword:`return` statement, the + :keyword:`!finally` clause will execute just prior to the + :keyword:`!break`, :keyword:`!continue` or :keyword:`!return` + statement's execution. + +* If a :keyword:`!finally` clause includes a :keyword:`!return` + statement, the returned value will be the one from the + :keyword:`!finally` clause's :keyword:`!return` statement, not the + value from the :keyword:`!try` clause's :keyword:`!return` + statement. For example:: -- cgit v0.12