Merged revisions 78182,78188 via svnmerge from

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  r78182 | georg.brandl | 2010-02-14 09:18:23 +0100 (So, 14 Feb 2010) | 1 line

  #7926: fix stray parens.
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  r78188 | georg.brandl | 2010-02-14 14:38:12 +0100 (So, 14 Feb 2010) | 1 line

  #7926: fix-up wording.
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This commit is contained in:
Georg Brandl 2010-02-14 13:40:45 +00:00
parent a920961673
commit 2fe3b3d4be
1 changed files with 8 additions and 6 deletions

View File

@ -346,9 +346,10 @@ A high-level explanation of the context management protocol is:
* The code in *BLOCK* is executed.
* If *BLOCK* raises an exception, the :meth:`__exit__(type, value, traceback)`
is called with the exception details, the same values returned by
:func:`sys.exc_info`. The method's return value controls whether the exception
* If *BLOCK* raises an exception, the context manager's :meth:`__exit__` method
is called with three arguments, the exception details (``type, value, traceback``,
the same values returned by :func:`sys.exc_info`, which can also be ``None``
if no exception occurred). The method's return value controls whether an exception
is re-raised: any false value re-raises the exception, and ``True`` will result
in suppressing it. You'll only rarely want to suppress the exception, because
if you do the author of the code containing the ':keyword:`with`' statement will
@ -459,7 +460,7 @@ could be written as::
with db_transaction(db) as cursor:
...
The :mod:`contextlib` module also has a :func:`nested(mgr1, mgr2, ...)` function
The :mod:`contextlib` module also has a ``nested(mgr1, mgr2, ...)`` function
that combines a number of context managers so you don't need to write nested
':keyword:`with`' statements. In this example, the single ':keyword:`with`'
statement both starts a database transaction and acquires a thread lock::
@ -468,8 +469,9 @@ statement both starts a database transaction and acquires a thread lock::
with nested (db_transaction(db), lock) as (cursor, locked):
...
Finally, the :func:`closing(object)` function returns *object* so that it can be
bound to a variable, and calls ``object.close`` at the end of the block. ::
Finally, the :func:`closing` function returns its argument so that it can be
bound to a variable, and calls the argument's ``.close()`` method at the end
of the block. ::
import urllib, sys
from contextlib import closing