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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Fri, 28 Feb 2014 22:26:07 -0700
Subject: Re: Tuples and immutability
To: Python <python-list@python.org>
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Xref: csiph.com comp.lang.python:67292

On Fri, Feb 28, 2014 at 6:27 PM, Eric Jacoboni <eric.jacoboni@gmail.com> wrote:
> Anyway, the TypeError should rollback, not commit the mistake.

The Python interpreter isn't a database.  It can't rollback the object
because the operation that was performed may not be reversible.
Consider for example a socket class where the += operator is
overloaded to send a message on the socket.  The message can't be
unsent.