the error (if any), or ensure that some cleanup takes place.
Note that you can use \code{@contextmanager} to define a context
-manager's \method{__context__} method. This is usually more convenient
-than creating another class just to serve as a context. For example:
+object's \method{__context__} method. This is usually more convenient
+than creating another class just to serve as a context manager.
+For example:
\begin{verbatim}
from __future__ import with_statement
do_something()
\end{verbatim}
-Note that if one of the nested contexts' \method{__exit__()} method
+Note that if the \method{__exit__()} method of one of the nested context managers
raises an exception, any previous exception state will be lost; the new
-exception will be passed to the outer contexts' \method{__exit__()}
-method(s), if any. In general, \method{__exit__()} methods should avoid
+exception will be passed to the \method{__exit__()} methods of any remaining
+outer context managers. In general, \method{__exit__()} methods should avoid
raising exceptions, and in particular they should not re-raise a
passed-in exception.
\end{funcdesc}
from contextlib import closing
import codecs
-with closing(codecs.open("foo", encoding="utf8")) as f:
+with closing(urllib.urlopen('http://www.python.org')) as f:
for line in f:
- print line.encode("latin1")
+ print line
\end{verbatim}
without needing to explicitly close \code{f}. Even if an error occurs,