[Python-checkins] python/nondist/peps pep-0307.txt,1.14,1.15

[gvanrossum@users.sourceforge.net]

Update of /cvsroot/python/python/nondist/peps
In directory sc8-pr-cvs1:/tmp/cvs-serv5765

Modified Files:
	pep-0307.txt 
Log Message:
Add posting-date.  Add note about the copy module.  Remove TBD -- this
PEP is complete AFAIAC.


Index: pep-0307.txt
===================================================================
RCS file: /cvsroot/python/python/nondist/peps/pep-0307.txt,v
retrieving revision 1.14
retrieving revision 1.15
diff -C2 -d -r1.14 -r1.15
*** pep-0307.txt	6 Feb 2003 20:38:30 -0000	1.14
--- pep-0307.txt	7 Feb 2003 18:11:29 -0000	1.15
***************
*** 8,12 ****
  Content-Type: text/plain
  Created: 31-Jan-2003
! Post-History: None
  
  
--- 8,12 ----
  Content-Type: text/plain
  Created: 31-Jan-2003
! Post-History: 7-Feb-2003
  
  
***************
*** 600,606 ****
  
  
! TBD
  
!     The rest of this PEP is still under construction!
  
  
--- 600,646 ----
  
  
! The copy module
  
!     Traditionally, the copy module has supported an extended subset of
!     the pickling APIs for customizing the copy() and deepcopy()
!     operations.
! 
!     In particular, besides checking for a __copy__ or __deepcopy__
!     method, copy() and deepcopy() have always looked for __reduce__,
!     and for classic classes, have looked for __getinitargs__,
!     __getstate__ and __setstate__.
! 
!     In Python 2.2, the default __reduce__ inherited from 'object' made
!     copying simple new-style classes possible, but slots and various
!     other special cases were not covered.
! 
!     In Python 2.3, several changes are made to the copy module:
! 
!     - The four- and five-argument return values of __reduce__ are
!       supported.
! 
!     - Before looking for a __reduce__ method, the
!       copy_reg.dispatch_table is consulted, just like for pickling.
! 
!     - When the __reduce__ method is inherited from object, it is
!       (unconditionally) replaced by a better one that uses the same 
!       APIs as pickle protocol 2: __getnewargs__, __getstate__, and
!       __setstate__, handling list and dict subclasses, and handling
!       slots.
! 
!     As a consequence of the latter change, certain new-style classes
!     that were copyable under Python 2.2 are not copyable under Python
!     2.3.  (These classes are also not picklable using pickle protocol
!     2.)  A minimal example of such a class:
! 
!         class C(object):
!             def __new__(cls, a):
!                 return object.__new__(cls)
! 
!     The problem only occurs when __new__ is overridden and has at
!     least one mandatory argument in addition to the class argument.
! 
!     To fix this, a __getnewargs__ method should be added that returns
!     the appropriate argument tuple (excluding the class).