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Re: while True or while 1

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On 01/23/2012 11:39 AM, Ian Kelly wrote:
> "We should forget about small efficiencies, say about 97% of the time:
> premature optimization is the root of all evil"
> -- Donald Knuth

To play devil's advocate for a moment, if you have the choice between 
two ways of writing something, A and B, where both are basically the 
same in terms of difficulty to write, difficulty to maintain, and 
difficulty to understand, but A is faster than B, even if just by a 
hair, why NOT write A?

It's like 'iter++' vs '++iter' in a C++ for loop. For ints, or for some 
iterators with optimization, it makes no difference. But the latter will 
be faster in debug builds, and *might* be faster in release builds if 
you have a complicated iterator. So why NOT make for(...; ...; ++i) the 
typical way of writing a for loop?

In the Python world, is 'while 1' any harder to understand than 'while 
True'? I'm about as staunch a supporter as you'll find for the idea that 
'while 1' should throw an exception, and even *I* think that 'while 1' 
is about the least-offensive idiom out there. If 'while 1' throws you 
off, I'd hate to see what you do when you learn that Python accepts 
loops like 'while x' where the condition evaluates to true if x is a 
non-zero integer and false if x is 0.


All that said, I like the 'while "stuff to do"' idea.

Evan

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Re: while True or while 1 Chris Angelico <rosuav@gmail.com> - 2012-01-22 01:59 +1100
  Re: while True or while 1 Erik Max Francis <max@alcyone.com> - 2012-01-21 13:13 -0800
    Re: while True or while 1 Chris Angelico <rosuav@gmail.com> - 2012-01-22 09:13 +1100
      Re: while True or while 1 Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-01-22 05:25 +0000
        Re: while True or while 1 Dan Sommers <dan@tombstonezero.net> - 2012-01-22 16:05 +0000
          Re: while True or while 1 alex23 <wuwei23@gmail.com> - 2012-01-22 19:55 -0800
            Re: while True or while 1 Dave Angel <d@davea.name> - 2012-01-23 08:02 -0500
              Re: while True or while 1 Hrvoje Niksic <hniksic@xemacs.org> - 2012-01-23 14:28 +0100
                Re: while True or while 1 Dave Angel <d@davea.name> - 2012-01-23 13:33 -0500
        Re: while True or while 1 MRAB <python@mrabarnett.plus.com> - 2012-01-22 16:13 +0000
    Re: while True or while 1 Grant Edwards <invalid@invalid.invalid> - 2012-01-23 15:51 +0000
    Re: while True or while 1 Giampaolo Rodolà <g.rodola@gmail.com> - 2012-01-23 17:41 +0100
      Re: while True or while 1 Erik Max Francis <max@alcyone.com> - 2012-01-23 11:12 -0800
        Re: while True or while 1 Giampaolo Rodolà <g.rodola@gmail.com> - 2012-01-23 21:20 +0100
    Re: while True or while 1 Ian Kelly <ian.g.kelly@gmail.com> - 2012-01-23 10:39 -0700
    Re: while True or while 1 Evan Driscoll <edriscoll@wisc.edu> - 2012-01-23 12:05 -0600
    Re: while True or while 1 Andrea Crotti <andrea.crotti.0@gmail.com> - 2012-01-23 20:50 +0000
      Re: while True or while 1 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-23 14:42 -0800
      Re: while True or while 1 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-23 14:42 -0800
      Re: while True or while 1 Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-01-24 03:37 +0000

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