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Date: Thu, 16 Jan 2014 16:01:56 +1100
Subject: Re: Guessing the encoding from a BOM
From: Chris Angelico <rosuav@gmail.com>
Cc: "python-list@python.org" <python-list@python.org>
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Xref: csiph.com comp.lang.python:64051

On Thu, Jan 16, 2014 at 1:13 PM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
>     if sig.startswith((b'\xFE\xFF', b'\xFF\xFE')):
>         return 'utf_16'
>     elif sig.startswith((b'\x00\x00\xFE\xFF', b'\xFF\xFE\x00\x00')):
>         return 'utf_32'

I'd swap the order of these two checks. If the file starts FF FE 00
00, your code will guess that it's UTF-16 and begins with a U+0000.

ChrisA