Velocity Reviews - Computer Hardware Reviews

Velocity Reviews > Newsgroups > Programming > Python > Re: for-loop on cmd-line

Reply
Thread Tools

Re: for-loop on cmd-line

 
 
Chris Angelico
Guest
Posts: n/a
 
      10-11-2012
On Thu, Oct 11, 2012 at 11:16 PM, D'Arcy J.M. Cain <(E-Mail Removed)> wrote:
> On Thu, 11 Oct 2012 13:24:22 +0200
> Gisle Vanem <(E-Mail Removed)> wrote:
>
>> Hello list. I'm a newbie when it comes to Python.
>>
>> I'm trying to turn this:
>>
>> def print_sys_path():
>> i = 0
>> for p in sys.path:
>> print ('sys.path[%2d]: %s' % (i, p))
>> i += 1
>>
>> into a one-line python command (in a .bat file):

>
> Is "one liner" an actual requirement or is the requirement to run it
> from the command line?
>
> python -c "
> import sys
> i = 0
> for p in sys.path:
> print('sys.path[%2d]: %s' % (i, p))
> i+=1
> "
>
> I don't know if this works on Windows or not.


It doesn't, I just tested it. Windows batch is appallingly crude
compared to a modern Unix shell; you may be able to find a way to get
around this, but the easiest solution for most batch files is going to
be an actual Python script file. You may be able to overlay your batch
and Python scripts with a trick like this:

rem = '''
@echo off
echo This is batch
\python32\python %0
echo All done
exit /b
rem '''
import sys
print("This is Python")
for i,p in enumerate(sys.path):
print('sys.path[%2d]: %s' % (i, p))
print("Python done")

You'll have a variable in Python called 'rem' which contains all your
batch code It exploits the fact that 'rem' makes a one-line
comment, but the triple quotes go across multiple lines. (The "exit
/b" should exit the batch script without closing cmd.exe - this is yet
another weird WEIRD wart in Windows batch. I'm pretty sure neither DOS
nor OS/2 batch required that parameter.)

ChrisA
 
Reply With Quote
 
 
 
 
Ramchandra Apte
Guest
Posts: n/a
 
      10-11-2012
On Thursday, 11 October 2012 18:44:44 UTC+5:30, Chris Angelico wrote:
> On Thu, Oct 11, 2012 at 11:16 PM, D'Arcy J.M. Cain <(E-Mail Removed)> wrote:
>
> > On Thu, 11 Oct 2012 13:24:22 +0200

>
> > Gisle Vanem <(E-Mail Removed)> wrote:

>
> >

>
> >> Hello list. I'm a newbie when it comes to Python.

>
> >>

>
> >> I'm trying to turn this:

>
> >>

>
> >> def print_sys_path():

>
> >> i = 0

>
> >> for p in sys.path:

>
> >> print ('sys.path[%2d]: %s' % (i, p))

>
> >> i += 1

>
> >>

>
> >> into a one-line python command (in a .bat file):

>
> >

>
> > Is "one liner" an actual requirement or is the requirement to run it

>
> > from the command line?

>
> >

>
> > python -c "

>
> > import sys

>
> > i = 0

>
> > for p in sys.path:

>
> > print('sys.path[%2d]: %s' % (i, p))

>
> > i+=1

>
> > "

>
> >

>
> > I don't know if this works on Windows or not.

>
>
>
> It doesn't, I just tested it. Windows batch is appallingly crude
>
> compared to a modern Unix shell; you may be able to find a way to get
>
> around this, but the easiest solution for most batch files is going to
>
> be an actual Python script file. You may be able to overlay your batch
>
> and Python scripts with a trick like this:
>
>
>
> rem = '''
>
> @echo off
>
> echo This is batch
>
> \python32\python %0
>
> echo All done
>
> exit /b
>
> rem '''
>
> import sys
>
> print("This is Python")
>
> for i,p in enumerate(sys.path):
>
> print('sys.path[%2d]: %s' % (i, p))
>
> print("Python done")
>
>
>
> You'll have a variable in Python called 'rem' which contains all your
>
> batch code It exploits the fact that 'rem' makes a one-line
>
> comment, but the triple quotes go across multiple lines. (The "exit
>
> /b" should exit the batch script without closing cmd.exe - this is yet
>
> another weird WEIRD wart in Windows batch. I'm pretty sure neither DOS
>
> nor OS/2 batch required that parameter.)
>
>
>
> ChrisA


What about the "Power" in PowerShell?
 
Reply With Quote
 
 
 
 
Ramchandra Apte
Guest
Posts: n/a
 
      10-11-2012
On Thursday, 11 October 2012 18:44:44 UTC+5:30, Chris Angelico wrote:
> On Thu, Oct 11, 2012 at 11:16 PM, D'Arcy J.M. Cain <(E-Mail Removed)> wrote:
>
> > On Thu, 11 Oct 2012 13:24:22 +0200

>
> > Gisle Vanem <(E-Mail Removed)> wrote:

>
> >

>
> >> Hello list. I'm a newbie when it comes to Python.

>
> >>

>
> >> I'm trying to turn this:

>
> >>

>
> >> def print_sys_path():

>
> >> i = 0

>
> >> for p in sys.path:

>
> >> print ('sys.path[%2d]: %s' % (i, p))

>
> >> i += 1

>
> >>

>
> >> into a one-line python command (in a .bat file):

>
> >

>
> > Is "one liner" an actual requirement or is the requirement to run it

>
> > from the command line?

>
> >

>
> > python -c "

>
> > import sys

>
> > i = 0

>
> > for p in sys.path:

>
> > print('sys.path[%2d]: %s' % (i, p))

>
> > i+=1

>
> > "

>
> >

>
> > I don't know if this works on Windows or not.

>
>
>
> It doesn't, I just tested it. Windows batch is appallingly crude
>
> compared to a modern Unix shell; you may be able to find a way to get
>
> around this, but the easiest solution for most batch files is going to
>
> be an actual Python script file. You may be able to overlay your batch
>
> and Python scripts with a trick like this:
>
>
>
> rem = '''
>
> @echo off
>
> echo This is batch
>
> \python32\python %0
>
> echo All done
>
> exit /b
>
> rem '''
>
> import sys
>
> print("This is Python")
>
> for i,p in enumerate(sys.path):
>
> print('sys.path[%2d]: %s' % (i, p))
>
> print("Python done")
>
>
>
> You'll have a variable in Python called 'rem' which contains all your
>
> batch code It exploits the fact that 'rem' makes a one-line
>
> comment, but the triple quotes go across multiple lines. (The "exit
>
> /b" should exit the batch script without closing cmd.exe - this is yet
>
> another weird WEIRD wart in Windows batch. I'm pretty sure neither DOS
>
> nor OS/2 batch required that parameter.)
>
>
>
> ChrisA


What about the "Power" in PowerShell?
 
Reply With Quote
 
Chris Angelico
Guest
Posts: n/a
 
      10-11-2012
On Fri, Oct 12, 2012 at 12:16 AM, Ramchandra Apte
<(E-Mail Removed)> wrote:
> What about the "Power" in PowerShell?


What about it? Are you suggesting that the OP use it? Are you saying
that Windows batch already includes it? You quoted my entire post
(double-spaced), but that context adds nothing to your statement; it
still stands alone as a complete non sequitur.

And you're posting to both c.l.p and p-l...

ChrisA
 
Reply With Quote
 
wxjmfauth@gmail.com
Guest
Posts: n/a
 
      10-11-2012
Le jeudi 11 octobre 2012 15:16:33 UTC+2, Ramchandra Apte a écrit*:

PS C:\> $cmd="import sys;"
PS C:\> $cmd+="print('\n'.join(sys.path))"
PS C:\> $cmd
import sys;print('\n'.join(sys.path))
PS C:\> c:\python32\python -c $cmd

C:\Windows\system32\python32.zip
c:\python32\DLLs
c:\python32\lib
c:\python32
c:\python32\lib\site-packages
PS C:\>

Can probably be in a .cmd file.

jmf
 
Reply With Quote
 
wxjmfauth@gmail.com
Guest
Posts: n/a
 
      10-11-2012
Le jeudi 11 octobre 2012 15:16:33 UTC+2, Ramchandra Apte a écrit*:

PS C:\> $cmd="import sys;"
PS C:\> $cmd+="print('\n'.join(sys.path))"
PS C:\> $cmd
import sys;print('\n'.join(sys.path))
PS C:\> c:\python32\python -c $cmd

C:\Windows\system32\python32.zip
c:\python32\DLLs
c:\python32\lib
c:\python32
c:\python32\lib\site-packages
PS C:\>

Can probably be in a .cmd file.

jmf
 
Reply With Quote
 
Gisle Vanem
Guest
Posts: n/a
 
      10-11-2012
<(E-Mail Removed)> wrote in comp.lang.python

(my ISP no longer updates this group. Last message is from 8. April.
Does the postings to the python mailing-list automatically get reposted
to comp.lang.python?)

> C:\Windows\system32\python32.zip
> c:\python32\DLLs


I see a similar result:
f:\Windows\system32\python27.zip

Where is it determined that python27.zip should be in sys.path?
I have no such file anywhere. I'm using ActivePython 2.7.2.

--gv

 
Reply With Quote
 
Chris Angelico
Guest
Posts: n/a
 
      10-11-2012
On Fri, Oct 12, 2012 at 3:49 AM, Gisle Vanem <(E-Mail Removed)> wrote:
> <(E-Mail Removed)> wrote in comp.lang.python
>
> (my ISP no longer updates this group. Last message is from 8. April.
> Does the postings to the python mailing-list automatically get reposted to
> comp.lang.python?)


Yes, c.l.p and python-list mirror each other.

>> C:\Windows\system32\python32.zip
>> c:\python32\DLLs

>
>
> I see a similar result:
> f:\Windows\system32\python27.zip
>
> Where is it determined that python27.zip should be in sys.path?
> I have no such file anywhere. I'm using ActivePython 2.7.2.


It's in sys.path in the three Windows Pythons I have here:

C:\Documents and Settings\M>python -c "import sys; print(sys.version); print('\n
'.join(sys.path))"
2.4.5 (#1, Jul 22 2011, 02:01:04)
[GCC 4.1.1]

C:\Program Files\LilyPond\usr\lib\python24.zip
C:\Program Files\LilyPond\usr\lib\python2.4
C:\Program Files\LilyPond\usr\lib\python2.4\plat-mingw32
C:\Program Files\LilyPond\usr\lib\python2.4\lib-tk
C:\Program Files\LilyPond\usr\lib\python2.4\lib-dynload
C:\Program Files\LilyPond\usr\lib\python2.4\site-packages

C:\Documents and Settings\M>\python26\python -c "import sys; print(sys.version);
print('\n'.join(sys.path))"
2.6.5 (r265:79096, Mar 19 2010, 21:48:26) [MSC v.1500 32 bit (Intel)]

C:\WINDOWS\system32\python26.zip
C:\python26\DLLs
C:\python26\lib
C:\python26\lib\plat-win
C:\python26\lib\lib-tk
C:\python26
C:\python26\lib\site-packages

C:\Documents and Settings\M>\python32\python -c "import sys; print(sys.version);
print('\n'.join(sys.path))"
3.2 (r32:88445, Feb 20 2011, 21:29:02) [MSC v.1500 32 bit (Intel)]

C:\WINDOWS\system32\python32.zip
C:\python32\DLLs
C:\python32\lib
C:\python32
C:\python32\lib\site-packages
C:\python32\lib\site-packages\win32
C:\python32\lib\site-packages\win32\lib
C:\python32\lib\site-packages\Pythonwin

C:\Documents and Settings\M>

Presumably it's so that I can zip up my entire Python library and toss
it into a convenient file. I don't think it costs much to stat a file
and find it's not there before moving on, so it's not a problem to
leave it there.

ChrisA
 
Reply With Quote
 
Prasad, Ramit
Guest
Posts: n/a
 
      10-11-2012
Chris Angelico wrote:

> On Fri, Oct 12, 2012 at 3:49 AM, Gisle Vanem <(E-Mail Removed)> wrote:

> > <(E-Mail Removed)> wrote in comp.lang.python
> >
> > (my ISP no longer updates this group.Last message is from 8. April.
> > Does the postings to the python mailing-list automatically get reposted to
> > comp.lang.python?)

>
> Yes, c.l.p and python-list mirror each other.
>

> >> C:\Windows\system32\python32.zip
> >> c:\python32\DLLs

> >
> >
> > I see a similar result:
> > f:\Windows\system32\python27.zip
> >
> > Where is it determined that python27.zip should be in sys.path?
> > I have no such file anywhere. I'm using ActivePython 2.7.2.

>
> It's in sys.path in thethree Windows Pythons I have here:
>
> C:\Documents and Settings\M>python -c "import sys; print(sys.version); print('\n
> '.join(sys.path))"
> 2.4.5 (#1, Jul 22 2011, 02:01:04)
> [GCC 4.1.1]
>
> C:\Program Files\LilyPond\usr\lib\python24.zip
> C:\Program Files\LilyPond\usr\lib\python2.4
> C:\Program Files\LilyPond\usr\lib\python2.4\plat-mingw32
> C:\Program Files\LilyPond\usr\lib\python2.4\lib-tk
> C:\Program Files\LilyPond\usr\lib\python2.4\lib-dynload
> C:\Program Files\LilyPond\usr\lib\python2.4\site-packages
>
> C:\Documents and Settings\M>\python26\python -c "import sys; print(sys.version);
> print('\n'.join(sys.path))"
> 2.6.5 (r265:79096, Mar 19 2010, 21:48:26) [MSC v.1500 32 bit (Intel)]
>
> C:\WINDOWS\system32\python26.zip
> C:\python26\DLLs
> C:\python26\lib
> C:\python26\lib\plat-win
> C:\python26\lib\lib-tk
> C:\python26
> C:\python26\lib\site-packages
>
> C:\Documents and Settings\M>\python32\python -c "import sys; print(sys.version);
> print('\n'.join(sys.path))"
> 3.2 (r32:88445, Feb 20 2011, 21:29:02) [MSC v.1500 32 bit (Intel)]
>
> C:\WINDOWS\system32\python32.zip
> C:\python32\DLLs
> C:\python32\lib
> C:\python32
> C:\python32\lib\site-packages
> C:\python32\lib\site-packages\win32
> C:\python32\lib\site-packages\win32\lib
> C:\python32\lib\site-packages\Pythonwin
>
> C:\Documents and Settings\M>
>
> Presumably it's so that I can zip upmy entire Python library and toss
> it into a convenient file. I don't think it costs much to stat a file
> and find it's not there before moving on, so it's not a problem to
> leave it there.
>
> ChrisA


Interesting, my results are slightly different. Here is what I
get from (one of) my Python installs.

2.7.1 (r271:86832, Nov 27 2010, 18:30:46) [MSC v.1500 32 bit (Intel)]
C:\ramit\Python27\python27.zip
C:\ramit\Python27\DLLs
C:\ramit\Python27\lib
C:\ramit\Python27\lib\plat-win
C:\ramit\Python27\lib\lib-tk
C:\ramit\Python27
C:\ramit\Python27\lib\site-packages

Ramit

This email is confidential and subject to important disclaimers and
conditions including on offers for the purchase or sale of
securities, accuracy and completeness of information, viruses,
confidentiality, legal privilege, and legal entity disclaimers,
available at http://www.jpmorgan.com/pages/disclosures/email.
 
Reply With Quote
 
 
 
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off




Advertisments