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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Thu, 30 May 2013 12:42:24 -0600
Subject: Re: How to get an integer from a sequence of bytes
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On Thu, May 30, 2013 at 12:26 PM, Mok-Kong Shen
<mok-kong.shen@t-online.de> wrote:
> Am 27.05.2013 17:30, schrieb Ned Batchelder:
>>
>> On 5/27/2013 10:45 AM, Mok-Kong Shen wrote:
>>>
>>> From an int one can use to_bytes to get its individual bytes,
>>> but how can one reconstruct the int from the sequence of bytes?
>>>
>> The next thing in the docs after int.to_bytes is int.from_bytes:
>> http://docs.python.org/3.3/library/stdtypes.html#int.from_bytes
>
>
> I am sorry to have overlooked that. But one thing I yet wonder is why
> there is no direct possibilty of converting a byte to an int in [0,255],
> i.e. with a constrct int(b), where b is a byte.

The bytes object can be viewed as a sequence of ints.  So if b is a
bytes object of non-zero length, then b[0] is an int in range(0, 256).