On Mon, May 3, 2010 at 7:16 AM, Thomas C. Hicks wrote:
> I am using Python 2.6.4 in Ubuntu. Since I use Ubuntu (with its every
> 6 months updates) and want to learn Python I have been working on a
> post-install script that would get my Ubuntu system up and running with
> my favorite packages qui
> If that looks a bit clumsy, use a generator expression:
>
> linesToDelete = [x for x in lines if x.startswith('%')]
> for x in linesToDelete:
> lines.remove(x)
>
> which idiomatically should probably become:
>
> for x in [y for y in lines if y.startswith('%')]:
> lines.remove(x)
>
>
Hmm, why
On Mon, May 3, 2010 at 1:49 AM, Stefan Behnel wrote:
>
> You are modifying the list during iteration, so the size changes and the
> iterator gets diverted. Don't remove the line, just skip over it, e.g.
>
> def read_package_names(open_text_file):
> """Read lines, strip any comments and r
On Mon, May 3, 2010 at 10:19 AM, Luke Paireepinart
wrote:
> Hmm, why not
> lines = [line for line in lines if not line.strip().startswith('%')]
I knew I missed something
--
André Engels, andreeng...@gmail.com
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Luke Paireepinart, 03.05.2010 10:27:
On Mon, May 3, 2010 at 1:49 AM, Stefan Behnel wrote:
You are modifying the list during iteration, so the size changes and the
iterator gets diverted. Don't remove the line, just skip over it, e.g.
def read_package_names(open_text_file):
"""Read
Luke Paireepinart, 03.05.2010 10:27:
On Mon, May 3, 2010 at 1:49 AM, Stefan Behnel wrote:
line = line.split('%', 1)[0]
lines = [line[:line.index('%')] for line in ...
Agreed that
line = line[:line.index('%')]
is slightly more readable than
line = line.split('%', 1)
On Mon, 3 May 2010 00:58:14 +0100
"Alan Gauld" wrote:
>
> "spir ☣" wrote
>
> > ...When writing "size = size + new_allocated" instead of
> > "size = new_allocated", It get a growth pattern of:
> >0 3 6 9 16 24 33 43 54 66 80 96 114
> > Which is not exactly what is stated in code, but rather
On Mon, May 3, 2010 at 3:50 AM, Stefan Behnel wrote:
> Luke Paireepinart, 03.05.2010 10:27:
>> What's this bizarre syntax?
>
> Look it up in the docs, it's called "with statement". Its purpose here is to
> make sure the file is closed after the execution of the statement's body,
> regardless of an
On Mon, 03 May 2010 10:55:11 +0200
Stefan Behnel wrote:
> Luke Paireepinart, 03.05.2010 10:27:
> > On Mon, May 3, 2010 at 1:49 AM, Stefan Behnel wrote:
> >> line = line.split('%', 1)[0]
> >
> > lines = [line[:line.index('%')] for line in ...
>
> Agreed that
>
> line = line[
On Mon, 3 May 2010 05:35:52 pm Andre Engels wrote:
> Don't change the list that you are iterating over. As you have found,
> it leads to (to most) unexpected results.
Or if you absolutely have to change the list in place, iterate over it
*backwards* (starting at the end, and moving towards the
2010/5/3 spir ☣ :
> On Mon, 03 May 2010 10:55:11 +0200
> Stefan Behnel wrote:
>
>> Luke Paireepinart, 03.05.2010 10:27:
>> > On Mon, May 3, 2010 at 1:49 AM, Stefan Behnel wrote:
>> >> line = line.split('%', 1)[0]
>> >
>> > lines = [line[:line.index('%')] for line in ...
>>
>> Agree
Luke Paireepinart, 03.05.2010 12:18:
On Mon, May 3, 2010 at 3:50 AM, Stefan Behnel wrote:
Luke Paireepinart, 03.05.2010 10:27:
I thought they changed for loop interations so that if you did
for line in open('packages.txt'):
etc...
it would automatically close the file handle after th
On Mon, 3 May 2010 08:18:41 pm Luke Paireepinart wrote:
> On Mon, May 3, 2010 at 3:50 AM, Stefan Behnel
wrote:
> > Luke Paireepinart, 03.05.2010 10:27:
> >> What's this bizarre syntax?
> >
> > Look it up in the docs, it's called "with statement". Its purpose
> > here is to make sure the file is c
On Mon, 03 May 2010 13:08:18 +0200
Stefan Behnel wrote:
> > Why aren't strings mutable, or lists immutable?
>
> What would be the use case of an immutable list, as opposed to a tuple? How
> would you use mutable strings in a dictionary?
[I'm not totally sure of the following, take it with so
I've just started to play with Tkinter and can't really figure out the
typical pattern of creating an app with several windows - I tried to
find some resources on the web but failed to find how to do this. Here
is an attempt to explain using code
class MyWindowClass:
def __init__(self):
self
> Agreed that
>
> line = line[:line.index('%')]
>
> is slightly more readable than
>
>line = line.split('%', 1)[0]
How about:
line = line.partition('%')[0]
partition() works even if '%' isn't present.
The index() and split() techniques raise exceptions if '%' isn't
present.
Malcolm
__
"The Green Tea Leaf" wrote
I've just started to play with Tkinter and can't really figure out the
typical pattern of creating an app with several windows - I tried to
find some resources on the web but failed to find how to do this. Here
is an attempt to explain using code
class MyWindowClass:
OK, thanks.
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