[Python-checkins] r67924 - python/trunk/Doc/tutorial/controlflow.rst

Wed Dec 24 17:10:05 CET 2008

Author: benjamin.peterson
Date: Wed Dec 24 17:10:05 2008
New Revision: 67924
Log:
pretend exceptions don't exist a while longer
Modified:
 python/trunk/Doc/tutorial/controlflow.rst
Modified: python/trunk/Doc/tutorial/controlflow.rst
==============================================================================

--- python/trunk/Doc/tutorial/controlflow.rst	(original)
+++ python/trunk/Doc/tutorial/controlflow.rst	Wed Dec 24 17:10:05 2008
@@ -169,42 +169,20 @@
 ... pass # Busy-wait for keyboard interrupt (Ctrl+C)
 ... 
 
-This is commonly used for creating minimal classes such as exceptions, or
-for ignoring unwanted exceptions::
+This is commonly used for creating minimal classes::
 
- >>> class ParserError(Exception):
+ >>> class MyEmptyClass:
 ... pass
- ... 
- >>> try:
- ... import audioop
- ... except ImportError:
- ... pass
- ... 
+ ...
 
 Another place :keyword:`pass` can be used is as a place-holder for a function or
-conditional body when you are working on new code, allowing you to keep
-thinking at a more abstract level. However, as :keyword:`pass` is silently
-ignored, a better choice may be to raise a :exc:`NotImplementedError`
-exception::
+conditional body when you are working on new code, allowing you to keep thinking
+at a more abstract level. The :keyword:`pass` is silently ignored::
 
 >>> def initlog(*args):
- ... raise NotImplementedError # Open logfile if not already open
- ... if not logfp:
- ... raise NotImplementedError # Set up dummy log back-end
- ... raise NotImplementedError('Call log initialization handler')
+ ... pass # Remember to implement this!
 ... 
 
-If :keyword:`pass` were used here and you later ran tests, they may fail
-without indicating why. Using :exc:`NotImplementedError` causes this code
-to raise an exception, telling you exactly where the incomplete code 
-is. Note the two calling styles of the exceptions above.
-The first style, with no message but with an accompanying comment, 
-lets you easily leave the comment when you remove the exception,
-which ideally would be a good description for
-the block of code the exception is a placeholder for. However, the 
-third example, providing a message for the exception, will produce 
-a more useful traceback.
-
 .. _tut-functions:
 
 Defining Functions
