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Multi-line commands with 'python -c'

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Since lines are so critical to Python syntax, I'm a little surprised
there's no majorly obvious solution to this... or maybe I'm just
blind.

Problem: Translate this into a shell one-liner:

import os
for root, dirs, files in os.walk("."):
    if len(dirs + files) == 1: print(root)

Solution 1: SyntaxError

python -c 'import os; for root, dirs, files in os.walk("."): if
len(dirs + files) == 1: print(root)'

You can't put a 'for' statement after an 'import' with just a semicolon.

Solution 2: SyntaxError

python -c 'import os\nfor root, dirs, files in os.walk("."): if
len(dirs + files) == 1: print(root)'

You can't put a backslash escape into your code like that! Makes no sense.

Solution 3: Silence

python -c 'import os' -c 'for root, dirs, files in os.walk("."): if
len(dirs + files) == 1: print(root)'

Haven't dug into exactly what this does, but the docs say that -c
terminates the option list, so I would guess that the second -c and
its arg get passed to the script.

Solution 4: Rely on the shell's ability to pass newlines inside arguments

$ python -c 'import os
> for root, dirs, files in os.walk("."):
>     if len(dirs + files) == 1: print(root)
> '

That works, but at that point, you aren't writing a one-liner any
more. It's also fiddly to edit.

Is there a better way to put multiple virtual lines into a 'python -c' command?

ChrisA

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Thread

Multi-line commands with 'python -c' Chris Angelico <rosuav@gmail.com> - 2014-05-30 10:52 +1000
  Re: Multi-line commands with 'python -c' Rustom Mody <rustompmody@gmail.com> - 2014-05-29 23:04 -0700
    Re: Multi-line commands with 'python -c' Rustom Mody <rustompmody@gmail.com> - 2014-05-29 23:45 -0700
      Re: Multi-line commands with 'python -c' Rustom Mody <rustompmody@gmail.com> - 2014-05-29 23:54 -0700
        Re: Multi-line commands with 'python -c' Peter Otten <__peter__@web.de> - 2014-05-30 09:33 +0200
      Re: Multi-line commands with 'python -c' Terry Reedy <tjreedy@udel.edu> - 2014-05-30 11:29 -0400
    Re: Multi-line commands with 'python -c' Chris Angelico <rosuav@gmail.com> - 2014-05-30 17:20 +1000
      Re: Multi-line commands with 'python -c' Rustom Mody <rustompmody@gmail.com> - 2014-05-30 05:47 -0700
        Re: Multi-line commands with 'python -c' Chris Angelico <rosuav@gmail.com> - 2014-05-30 22:58 +1000
  Re: Multi-line commands with 'python -c' Duncan Booth <duncan.booth@invalid.invalid> - 2014-05-30 21:11 +0000
    Re: Multi-line commands with 'python -c' Devin Jeanpierre <jeanpierreda@gmail.com> - 2014-05-30 14:42 -0700
    Re: Multi-line commands with 'python -c' Chris Angelico <rosuav@gmail.com> - 2014-05-31 07:47 +1000
      Re: Multi-line commands with 'python -c' Duncan Booth <duncan.booth@invalid.invalid> - 2014-05-31 16:41 +0000
        Re: Multi-line commands with 'python -c' Peter Otten <__peter__@web.de> - 2014-05-31 19:11 +0200
          Re: Multi-line commands with 'python -c' Duncan Booth <duncan.booth@invalid.invalid> - 2014-06-01 20:43 +0000

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