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Date: Tue, 25 Sep 2012 08:57:56 +1000
Subject: Re: python file API
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:29951

On Tue, Sep 25, 2012 at 8:37 AM, Ian Kelly <ian.g.kelly@gmail.com> wrote:
> On Mon, Sep 24, 2012 at 4:14 PM, Chris Angelico <rosuav@gmail.com> wrote:
>> file.pos = 42 # Okay, you're at position 42
>> file.pos -= 10 # That should put you at position 32
>> foo = file.pos # Presumably foo is the integer 32
>> file.pos -= 100 # What should this do?
>
> Since ints are immutable, the language specifies that it should be the
> equivalent of "file.pos = file.pos - 100", so it should set the file
> pointer to 68 bytes before EOF.

Oh, I forgot that guaranteed equivalency. Well, at least it removes
the ambiguity. I don't like it though.

ChrisA