Re: [boost] Futures Review - Should packaged_taskbeCopyConstructible?

Subject: Re: [boost] Futures Review - Should packaged_taskbeCopyConstructible?
From: Anthony Williams (anthony.ajw_at_[hidden])
Date: 2009-02-11 03:31:27

"vicente.botet" <vicente.botet_at_[hidden]> writes:

> Sorry i was not clear. The problem is that the reference to the task 
>
>    std::packaged_task<result_type> task(std::move(f));
>
> has been stored in the set_wait_callback. But this address is no more
> valable when the function returns, so when the user gets the future
> and call to get, the callback uses a bad address. Hoping it is clear
> now.

Yes, it's clear. That's a design issue with set_wait_callback.

> Ok, I see. Anyway, I think that examples like 
>  template<typename F>
> std::packaged_task<typename std::result_of<F()>::type> lazy_call(F f);
>
> should be included in the library, at least as an example.

That's a good idea.

Anthony
-- 
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