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Re: Using try-catch to handle multiple possible file types?

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Date Tue, 19 Nov 2013 18:22:50 +1100
Subject Re: Using try-catch to handle multiple possible file types?
From Chris Angelico <rosuav@gmail.com>
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On Tue, Nov 19, 2013 at 6:13 PM, Victor Hooi <victorhooi@gmail.com> wrote:
> My first thought was to use a try-catch block and attempt to open it using the most common filetype, then if that failed, try the next most common type etc. before finally erroring out.
>
> So basically, using exception handling for flow-control.
>
> However, is that considered bad practice, or un-Pythonic?

It's fairly common to work that way. But you may want to be careful
what order you try them in; some codecs might be technically capable
of reading other formats than you wanted, so start with the most
specific.

Alternatively, looking at a file's magic number (either with
python-magic/libmagic or by manually reading in a few bytes) might be
more efficient. Either way can work, take your choice!

ChrisA

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Thread

Using try-catch to handle multiple possible file types? Victor Hooi <victorhooi@gmail.com> - 2013-11-18 23:13 -0800
  Re: Using try-catch to handle multiple possible file types? Chris Angelico <rosuav@gmail.com> - 2013-11-19 18:22 +1100
  Re: Using try-catch to handle multiple possible file types? Amit Saha <amitsaha.in@gmail.com> - 2013-11-19 17:22 +1000
  Re: Using try-catch to handle multiple possible file types? Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-11-19 09:36 +0000
    Re: Using try-catch to handle multiple possible file types? Victor Hooi <victorhooi@gmail.com> - 2013-11-19 16:30 -0800
      Re: Using try-catch to handle multiple possible file types? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-11-20 01:56 +0000
        Re: Using try-catch to handle multiple possible file types? Neil Cerutti <mr.cerutti@gmail.com> - 2013-11-20 10:05 -0500
      Re: Using try-catch to handle multiple possible file types? Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-11-20 01:50 +0000

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