comp.lang.python Google Group

Re: New syntax for blocks

2009-11-13T04:10:29Z

On Nov 12, 7:44 pm, Steven D'Aprano <st...@REMOVE-THIS-
cybersource.com.au> wrote
OK, what *if* the variable would only be valid in *that* block and
*that* block only! My first idea was to have the variable avaiable in
the local scope (if that is correct terminology?) so if the
conditional was in global space the value would be available in global

2.6 and sys.exit()

2009-11-13T04:07:15Z

Hello,
I have the following in exit.py:
import sys
sys.exit(0)
I now try 'python -i exit.py':
In 2.5, the script exits as I would expect.
In 2.6, the following error is printed:
Traceback (most recent call last):
File "exit.py", line 2, in <module>
sys.exit(0)
SystemExit: 0
I couldn't find anything related to this in "What's new in 2.6".

Re: ANN: esky 0.2.1

2009-11-13T03:39:54Z

Not sure if it's officially supported, but I do most of my development
on Python 2.6 and bbfreeze hasn't given me any problems as yet.
Cheers,
Ryan

Re: python parser overridden by pymol

2009-11-13T03:33:38Z

As I said before, I don't know pymol. But if that is the package name,
then Robert is certainly right. You need to read the docs on pymol to
see what they require. For example, it's surprising they require a
separate PYMOL_PATH environment variable, since they can find their own
directory path with the __file__ attribute of one of the modules.

Re: ANN: esky 0.2.1

2009-11-13T03:19:55Z

In article <mailman.23.1257600051.2873.py thon-l...@python.org>,
Recently I was looking into distribution mechanisms, and I passed over
bbfreeze because I saw no indication that Python 2.6 was supported.
Kind of a bummer because esky looks pretty cool.

Re: Does turtle graphics have the wrong associations?

2009-11-13T03:13:18Z

[I'll be honest and say that I merely glanced at the two
pdf files.]
Who is your target audience? The opening Getting Started
paragraph would probably put off many beginners right from
the get go! You're talking about a 'first language' but
throwing 'syntax', 'windows', 'graphics', 'networking',
'file and database access' and 'standard libraries' at them.

Re: Writing an emulator in python - implementation questions (for performance)

2009-11-13T03:12:52Z

It's easy enough to test:
0.32850909233093262
0.54839301109313965
The shift and mask are a little faster on my machine, but that's
certainly what I would call a micro-optimization. Unless the divmod call
is the bottleneck in your code -- and it almost certainly won't be -- I
don't think it's worth the obfuscation to use shift/mask. What should be

Re: Python & Go

2009-11-13T03:08:39Z

It looks like a not-so-interesting C follow-on, but the article doesn't
describe any of the parallelism stuff.
Nah, exceptions are an ugly effect that gets in the way of
parallelism. Haskell handles lookups through its type system; dealing
with lookup errors (say by chaining the Maybe type) is clean and

Re: Writing an emulator in python - implementation questions (for performance)

2009-11-13T03:00:16Z

I don't know about that...
Python on a 2GHz processor (which is more or less entry-level for desktop
PCs these days), emulating something which used to run at 2.5MHz? Even if
the Python code does 1000 times more work, the modern processor is nearly
1000 times faster, so your Python code won't be much slower than the

Re: python simply not scaleable enough for google?

2009-11-13T02:50:33Z

Quite slow to do what? Quite slow compared to what?
I think you'll find using CPython to sort a list of ten million integers
will be quite a bit faster than using bubblesort written in C, no matter
how efficient the C compiler.
And why are we limiting ourselves to integers representable by the native

Re: #define (from C) in Python

2009-11-13T02:36:42Z

Or use a different preprocessor, such as m4, that
doesn't clash with the # character.

Re: python parser overridden by pymol

2009-11-13T02:32:32Z

No, do not do this. Add /usr/lib/pymodules/python2.5/ to your $PYTHONPATH, *not*
/usr/lib/pymodules/python2.5/p ymol/. You will continue to run into problems if
you do it this way. You are not supposed to put the directory *of* the package
onto sys.path but rather the directory that *contains* the package directory.

Re: Writing an emulator in python - implementation questions (for performance)

2009-11-13T02:33:53Z

Not necessarily, because it involves a function call,
and constructing and deconstructing a result tuple.
If you time them, you may well find that the explicit
shift and mask operations turn out to be faster.
That also goes for any of the other things being
discussed here. Especially if you're used to C, one's

Re: Writing an emulator in python - implementation questions (for performance)

2009-11-13T02:29:03Z

But keep in mind that named "constants" at the module level
are really global variables, and therefore incur a dictionary
lookup every time they're used.
For maximum speed, nothing beats writing the numeric literals
directly into the code, unfortunately.
Generally, I think you're going to have quite a battle on

Re: python with echo

2009-11-13T02:22:26Z

You want to be able to distinguish between a child process terminating
with an exit status, and failing to run a child process for some reason.