Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.lang.python > #63111

Re: Strange behaviour with a for loop.

From Mark Lawrence <breamoreboy@yahoo.co.uk>
Subject Re: Strange behaviour with a for loop.
Date 2014-01-04 05:38 +0000
References <4DC5A4FC-CCAF-446B-B41C-23E52C2389B6@icloud.com>
Newsgroups comp.lang.python
Message-ID <mailman.4891.1388813882.18130.python-list@python.org> (permalink)

Show all headers | View raw


On 04/01/2014 04:03, Sean Murphy wrote:
> Hello all.
>
> This is a newly question. But I wish to understand why the below code is providing different results.
>
> import os, sys
>
>
> if len(sys.argv) > 2:
>    filenames = sys.argv[1:]
> else
>    print ("no parameters provided\n")
>    sys.edit()
>
> for filename in filenames:
>    print ("filename is: %s\n" %filename)
>
> The above code will return results like:
>
> filename is test.txt
>
> If I modify the above script slightly as shown below, I get a completely different result.
>
> if len(sys.argv) > 2:
>    filenames = sys.argv[1]
> else
>    print ("no parameters provided\n")
>    sys.exit()
>
> for filename in filenames:
>    print ("filename is:  %s\n" % filename)
>
> The result is the filename is spelled out a character at a time. The bit I am missing is something to do with splicing or referencing in Python.
>
> Why am I getting different results? In other languages I would have got the whole content of the element when using the index of the array (list).
>
>
> Sean
> filename is: t
> filename
>

As you've already had answers I'd like to point out that your test for 
len(sys.argv) is wrong, else is missing a colon and sys.edit() is very 
unlikely to work :)

-- 
My fellow Pythonistas, ask not what our language can do for you, ask 
what you can do for our language.

Mark Lawrence

Back to comp.lang.python | Previous | Next | Find similar | Unroll thread


Thread

Re: Strange behaviour with a for loop. Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-01-04 05:38 +0000

csiph-web