Re: Equivalent of boost::val?

From:
Peter Dimov <pdimov@gmail.com>
Newsgroups:
comp.lang.c++.moderated
Date:
Mon, 31 Dec 2007 02:02:40 CST
Message-ID:
<225787f7-c779-4817-9cdf-9fc6cabf941d@e23g2000prf.googlegroups.com>
On Dec 29, 10:36 pm, Al <t...@haik.us> wrote:

Hi there,

I have a function that takes a const reference. Say

void foo(const int& i);

I want to execute this function in a separate thread; I can use
boost::bind to do so. E.g.:

// ...
const int i = 5;
boost::bind(foo, i);

The above works fine in the absence of threads. However, when executed
in a separate thread, the current thread's stack will have most likely
disappeared already (the parent function does not / can not wait() on
it). So foo would receive garbage or worse.


....

So, I was wondering if there is a language or boost way of doing
something like:

boost::bind(foo, boost::val(i));

So that `i' is copied over to the other thread's stack instead of being
passed by reference. In a sense, the reverse of boost::ref.


boost::bind( foo, i ). The default is to make a copy. boost::ref
overrides the default and stores a reference.

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