. Python 2.1 function attributes

[Justin Sheehy]

"Tim Peters" <tim.one at home.com> writes:

> "print >>"

> would-be-more-impressed-by-the-damnation-of-people-who've-actually-
>     tried-it-ly y'rs  - tim

I've actually tried it, and I don't like it.

When 2.0 started to approach release time, I made a point of using the
new features in new code in cases where the program wouldn't have to
run anywhere other than my own workstation.  (That restriction was
caused by the fact that it is non-trivial for me to get a new Python
version onto all of the machines that I care about.)

My thoughts on a few of the notable new features:

 - list comprehensions

   Very well done.  I don't find myself using them very often yet, but 
   I approve of these both conceptually and in Python's implementation.

   I suspect that once 2.0 becomes as ubiquitous as 1.5.x, I will
   begin to use these more heavily.  That might depend on whether
   their speed improves.  I'm not sure, since I haven't used them
   enough yet to determine if that will be a bottleneck for me.

 - augmented assignment

   Overall, I am glad this made it in.  Sometimes, it is more
   convenient and more clear than (e.g.) a = a + b.  I recognize the huge
   value of augmented assignment in certain situations (such as large
   matrices in Numeric).  However, I think that there is another side
   to this.

   The varying-behavior-depending-on-mutability aspect of += (which is
   necessary for it to be useful) is likely to cause some confusion.
   Admittedly, the ones most confused will probably be the ones that
   don't quickly grok Python's name, assignment and reference models.

   The fact that += sometimes acts like = but sometimes acts
   like a method call seems like a flaw to me.  Since I can't think of 
   a better way to solve the problem, I'll shut up about it now.

 - print >>

   Ugly.  Really ugly.

   Perhaps I don't count, though, since I didn't use the print
   statement very much before anyway.  I tend to only use "print" either
   for crude debugging or for simple scripts.  For most output I use
   fd.write() with heavy applciation of the %s format character.

   I tried using the new print statement, though.  I found that while
   it made some code shorter, it also made it look (to my eyes) less
   Pythonic.  Using a series of special characters in order to save a few
   lines of space seems more like something done by That Other P Language,
   and less like something that meets with Python's usual simplicity
   and explicitness.

   I know it won't change now.  I don't hate it enough to try to
   demand that it be excised, in any case.  But I also know that I
   don't expect to use it in anything I write anytime soon.

 damnation?-you-asked-for-it-you-got-it-ly y'rs

-Justin