In Python 2.x, exceptions in finally blocks are not normalized. Since with
statements are implemented using finally blocks, ceval.c had to be tweaked to
distinguish between with finally blocks and normal ones.
A test for the finalization of generators containing with statements was also
added.
in http://codereview.appspot.com/53094 and accepted by Guido.
The construct is transformed into multiple With AST nodes so that
there should be no problems with the semantics.
discussion.
There are two places of documentation that still mention __context__:
Doc/lib/libstdtypes.tex -- I wasn't quite sure how to rewrite that without
spending a whole lot of time thinking about it; and whatsnew, which Andrew
usually likes to change himself.
uses of it in test_with.py. As a result, test_with has been skipped
(due to failing imports) on all buildbot boxes since. Alas, that's
not a test failure -- you have to pay attention to the
1 skip unexpected on PLATFORM:
test_with
kinds of output at the ends of test runs to notice that this got
broken.
It's likely that more renaming in test_with.py would be desirable.
Anyway, this is the changes to the with-statement
so that __exit__ must return a true value in order
for a pending exception to be ignored.
The PEP (343) is already updated.
- New semantics for __exit__() -- it must re-raise the exception
if type is not None; the with-statement itself doesn't do this.
(See the updated PEP for motivation.)
- Added context managers to:
- file
- thread.LockType
- threading.{Lock,RLock,Condition,Semaphore,BoundedSemaphore}
- decimal.Context
- Added contextlib.py, which defines @contextmanager, nested(), closing().
- Unit tests all around; bot no docs yet.
This was started by Mike Bland and completed by Guido
(with help from Neal).
This still needs a __future__ statement added;
Thomas is working on Michael's patch for that aspect.
There's a small amount of code cleanup and refactoring
in ast.c, compile.c and ceval.c (I fixed the lltrace
behavior when EXT_POP is used -- however I had to make
lltrace a static global).
Benjamin Peterson
Ezio Melotti
Senthil Kumaran
Georg Brandl
Amaury Forgeot d'Arc
Nick Coghlan
Guido van Rossum
Tim Peters
Phillip J. Eby
Thomas Wouters