[Python-checkins] CVS: python/nondist/peps pep-0201.txt,1.3,1.4

[Barry Warsaw]

Update of /cvsroot/python/python/nondist/peps
In directory slayer.i.sourceforge.net:/tmp/cvs-serv28717

Modified Files:
	pep-0201.txt 
Log Message:
Added a few more open issues:

- what should "zip()" do (i.e. zip with no arguments).

- should zip() be included in the builtins?

- the padtuple proposal


Index: pep-0201.txt
===================================================================
RCS file: /cvsroot/python/python/nondist/peps/pep-0201.txt,v
retrieving revision 1.3
retrieving revision 1.4
diff -C2 -r1.3 -r1.4
*** pep-0201.txt	2000/07/19 04:19:54	1.3
--- pep-0201.txt	2000/07/24 17:40:00	1.4
***************
*** 126,130 ****
      nor will zip() ever raise an exception with lists of different
      lengths.  To accomplish either behavior, the sequences must be
!     checked and processed before the call to zip().
  
  
--- 126,131 ----
      nor will zip() ever raise an exception with lists of different
      lengths.  To accomplish either behavior, the sequences must be
!     checked and processed before the call to zip() -- but see the Open
!     Issues below for more discussion.
  
  
***************
*** 391,394 ****
--- 392,403 ----
        Current scoring seems to generally favor outcome 1.
  
+     - What should "zip()" do?
+ 
+       Along similar lines, zip() with no arguments (or zip() with just
+       a pad argument) can have ambiguous semantics.  Should this
+       return no elements or an infinite number?  For these reaons,
+       raising a TypeError exception in this case makes the most
+       sense.
+ 
      - The name of the built-in `zip' may cause some initial confusion
        with the zip compression algorithm.  Other suggestions include
***************
*** 399,402 ****
--- 408,429 ----
        with `zip' because the same functionality is available in other
        languages (e.g. Haskell) under the name `zip'[2].
+ 
+     - Should zip() be including in the builtins module or should it be
+       in a separate generators module (possibly with other candidate
+       functions like irange())?
+ 
+     - Padding short sequences with different values.  A suggestion has
+       been made to allow a `padtuple' (probably better called `pads'
+       or `padseq') argument similar to `pad'.  This sequence must have
+       a length equal to the number of sequences given.  It is a
+       sequence of the individual pad values to use for each sequence,
+       should it be shorter than the maximum length.
+ 
+       One problem is what to do if `padtuple' itself isn't of the
+       right length?  A TypeError seems to be the only choice here.
+ 
+       How does `pad' and `padtuple' interact?  Perhaps if padtuple
+       were too short, it could use pad as a fallback.  padtuple would
+       always override pad if both were given.