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Re: How to use "while" within the command in -c option of python?

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On Sun, Oct 14, 2012 at 5:21 AM, Joshua Landau
<joshua.landau.ws@gmail.com> wrote:
> Because Python uses indentation, what would "if A: print(1); if B: print(2)"
> even do? It has to fail, because we have to assume consistent indentation
> for ";"s*. With "\n" as I proposed, you still have to indent: it is just a
> method to bypass lame shells [it would become "if A: print(1)\nif B:
> print(2)"].

sikorsky@sikorsky:~/cpython$ python -c "if False: print(1); print(2)"
sikorsky@sikorsky:~/cpython$ python -c "if True: print(1); print(2)"
1
2
sikorsky@sikorsky:~/cpython$

The semicolon separates statements, but doesn't change nesting levels.
The if statement increases the nesting level, which demands a
corresponding indentation increase if you go onto a new line; the
statement you describe is illegal because the 'if' isn't allowed to
not be at the beginning of the line, but it's unambiguous.

Of course, since Python lacks a non-whitespace way of indicating the
end of an if block, there's no way to put your "if A" and "if B" onto
the same line as peers. But that's a consequence of a design decision,
and one that can't easily be changed. Every language has warts like
that; eschewing variable declarations prevents infinite nesting of
scopes, but demanding variable declarations makes interactive work
harder. To paraphrase the Pirate King: Always follow the dictates of
your conscience, and accept the consequences.

ChrisA

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Re: How to use "while" within the command in -c option of python? Etienne Robillard <animelovin@gmail.com> - 2012-10-12 19:04 -0400
  Re: How to use "while" within the command in -c option of python? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-10-13 00:32 +0000
    Re: How to use "while" within the command in -c option of python? Thomas Bach <thbach@students.uni-mainz.de> - 2012-10-13 10:41 +0200
    Re: How to use "while" within the command in -c option of python? Chris Angelico <rosuav@gmail.com> - 2012-10-13 20:03 +1100
    Re: How to use "while" within the command in -c option of python? Chris Angelico <rosuav@gmail.com> - 2012-10-14 04:23 +1100
      Re: How to use "while" within the command in -c option of python? Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2012-10-13 20:43 +0300
        Re: How to use "while" within the command in -c option of python? Chris Angelico <rosuav@gmail.com> - 2012-10-14 04:47 +1100
    Re: How to use "while" within the command in -c option of python? Chris Angelico <rosuav@gmail.com> - 2012-10-14 05:41 +1100
    Re: How to use "while" within the command in -c option of python? Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2012-10-13 15:19 -0400
    Re: How to use "while" within the command in -c option of python? Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2012-10-13 16:42 -0400
    Re: How to use "while" within the command in -c option of python? Chris Angelico <rosuav@gmail.com> - 2012-10-14 08:39 +1100
    Re: How to use "while" within the command in -c option of python? Chris Angelico <rosuav@gmail.com> - 2012-10-14 09:09 +1100

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