Update of /cvsroot/python/python/nondist/peps
In directory usw-pr-cvs1:/tmp/cvs-serv27556
Modified Files:
pep-0285.txt
Log Message:
On the eve of posting this to c.l.py, add a response to a common but
nonsensical suggestion (that x == True should hold for all true x).
Index: pep-0285.txt
===================================================================
RCS file: /cvsroot/python/python/nondist/peps/pep-0285.txt,v
retrieving revision 1.9
retrieving revision 1.10
diff -C2 -d -r1.9 -r1.10
*** pep-0285.txt 30 Mar 2002 05:02:42 -0000 1.9
--- pep-0285.txt 30 Mar 2002 05:16:16 -0000 1.10
***************
*** 204,207 ****
--- 204,220 ----
lowercase alternatives if enough people think it looks better.
+ It has been suggested that, in order to satisfy user expectations,
+ for every x that is considered true in a Boolean context, the
+ expression x == True should be true, and likewise if x is
+ considered false, x == False should be true. This is of course
+ impossible; it would mean that e.g. 6 == True and 7 == True, from
+ which one could infer 6 == 7. Similarly, [] == False == None
+ would be true, and one could infer [] == None, which is not the
+ case. I'm not sure where this suggestion came from; it was made
+ several times during the first review period. For truth testing
+ of a value, one should use "if", e.g. "if x: print 'Yes'", not
+ comparison to a truth value; "if x == True: print 'Yes'" is not
+ only wrong, it is also strangely redundant.
+
Implementation
In directory usw-pr-cvs1:/tmp/cvs-serv27556
Modified Files:
pep-0285.txt
Log Message:
On the eve of posting this to c.l.py, add a response to a common but
nonsensical suggestion (that x == True should hold for all true x).
Index: pep-0285.txt
===================================================================
RCS file: /cvsroot/python/python/nondist/peps/pep-0285.txt,v
retrieving revision 1.9
retrieving revision 1.10
diff -C2 -d -r1.9 -r1.10
*** pep-0285.txt 30 Mar 2002 05:02:42 -0000 1.9
--- pep-0285.txt 30 Mar 2002 05:16:16 -0000 1.10
***************
*** 204,207 ****
--- 204,220 ----
lowercase alternatives if enough people think it looks better.
+ It has been suggested that, in order to satisfy user expectations,
+ for every x that is considered true in a Boolean context, the
+ expression x == True should be true, and likewise if x is
+ considered false, x == False should be true. This is of course
+ impossible; it would mean that e.g. 6 == True and 7 == True, from
+ which one could infer 6 == 7. Similarly, [] == False == None
+ would be true, and one could infer [] == None, which is not the
+ case. I'm not sure where this suggestion came from; it was made
+ several times during the first review period. For truth testing
+ of a value, one should use "if", e.g. "if x: print 'Yes'", not
+ comparison to a truth value; "if x == True: print 'Yes'" is not
+ only wrong, it is also strangely redundant.
+
Implementation