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Re: [ub] Type punning to avoid copying

From: Jeffrey Yasskin <jyasskin_at_[hidden]>
Date: Mon, 9 Sep 2013 09:49:25 -0700
On Sun, Sep 8, 2013 at 9:48 PM, Gabriel Dos Reis <gdr_at_[hidden]> wrote:
> | In fact, it is not at clear that either programmers or compilers want
> | a notion of 'object resuscitation'.
> |
> |
> | I don't know what you mean by 'resuscitation' here. Can you elaborate?
>
> Resuscitation here refer to the idea that
>
> "there exists a set of times when objects' lifetimes begin and end, and
> that set gives the program defined behavior, then the program has
> defined behavior"
>
> If we don't have a uniquely defined point in time where the lifetime of
> an object starts, that means that either it never started or it started
> and ended multitple times.

I think you've misread Richard here. He didn't say "a set of times
when an object's (singular, possessive) lifetimes begin and end"; he
said "a set of times when objects' (plural, possessive) lifetimes
begin and end". I read that as a mapping of an object to the point in
time when its lifetime begins and the point in time when its lifetime
ends.

Jeffrey

Received on 2013-09-09 18:49:46