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Update contextlib documentation to use the same terminology as the module implementation

This commit is contained in:
Nick Coghlan 2006-04-23 15:14:37 +00:00
parent 84faa85775
commit 5ef9d9fdb9
1 changed files with 8 additions and 7 deletions
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15
Doc/lib/libcontextlib.tex
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@ -49,8 +49,9 @@ occurred. Thus, you can use a
the error (if any), or ensure that some cleanup takes place. the error (if any), or ensure that some cleanup takes place.
Note that you can use \code{@contextmanager} to define a context Note that you can use \code{@contextmanager} to define a context
manager's \method{__context__} method. This is usually more convenient object's \method{__context__} method. This is usually more convenient
than creating another class just to serve as a context. For example: than creating another class just to serve as a context manager.
For example:
\begin{verbatim} \begin{verbatim}
from __future__ import with_statement from __future__ import with_statement
@ -97,10 +98,10 @@ with A as X:
do_something() do_something()
\end{verbatim} \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 raises an exception, any previous exception state will be lost; the new
exception will be passed to the outer contexts' \method{__exit__()} exception will be passed to the \method{__exit__()} methods of any remaining
method(s), if any. In general, \method{__exit__()} methods should avoid outer context managers. In general, \method{__exit__()} methods should avoid
raising exceptions, and in particular they should not re-raise a raising exceptions, and in particular they should not re-raise a
passed-in exception. passed-in exception.
\end{funcdesc} \end{funcdesc}
@ -127,9 +128,9 @@ from __future__ import with_statement
from contextlib import closing from contextlib import closing
import codecs 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: for line in f:
print line.encode("latin1") print line
\end{verbatim} \end{verbatim}
without needing to explicitly close \code{f}. Even if an error occurs, without needing to explicitly close \code{f}. Even if an error occurs,