Boost logo

Boost :

Subject: Re: [boost] [atomic] (op)_and_test naming
From: Rob Stewart (rstewart_at_[hidden])
Date: 2018-01-25 11:32:15


On January 24, 2018 6:32:01 PM EST, Gavin Lambert via Boost <boost_at_[hidden]> wrote:
> On 25/01/2018 00:35, Andrey Semashev wrote:
> > I would like to ask for the community opinion on the naming of the
> > (op)_and_test functions that appeared in Boost.Atomic 1.66.
>
> For clarity, I was the one who filed the issue mentioned in the OP.
>
> My argument is the following:
>
> * "if (x)" is true when x is an integer type that is nonzero. (And
> this convention is often extended to non-integer types as well, for
> suitable definitions of "zero".)
> * "atomic_flag::test_and_set" is true when the flag was previously
> set.
> * "atomic<T>::bit_test_and_set" is true when the bit was previously
> 1/set.
> * "atomic<T>::fetch_add" returns the value prior to the add, which is
> true if nonzero due to the first rule.
>
> It thus seems peculiar to have "atomic<>::add_and_test" return true
> when the result is zero.

Your consistency argument seems compelling, unless there are unidentified counterexamples.

--
Rob
(Sent from my portable computation device.)

Boost list run by bdawes at acm.org, gregod at cs.rpi.edu, cpdaniel at pacbell.net, john at johnmaddock.co.uk