From: shunsuke (pstade.mb_at_[hidden])
Date: 2007-03-22 04:55:58
Daniel Walker wrote:
> On 3/21/07, shunsuke <pstade.mb_at_[hidden]> wrote:
>> Daniel Walker wrote:
>>> If/when lambda standardizes on
>>> result<>, the lambda related special cases in result_of can be
>> It will break a code using not result_of but sig compatible functors?
> Yes. That's the reason lambda would support both for a time with sig<>
> being deprecated. After a release or two (giving users plenty of time
> to update their code) sig<> would be removed. This gives them a fair
> warning and time to adapt.
I think users don't want to spend the time.
Smart users will protect themselves right now by using something like..
: enable_result_of_sig // added
Hmm, patch is no longer required. :-)
>> Can the patch support a sig compatible functor
>> which is "nullary-callable" (e.g. lambda::constructor<>) ?
> Yes. I just tested it with lambda::constructor<>, and it does work.
I tried this:
int i = 1;
r = constructor<int>()(i); // (1) GCC compiles.
r = constructor<int>()(); // (2) GCC fails.
I guess a sig-compatible functor which is nullary-callable must be
ported to result_of, even if the patch is applied.
Note that nullary instantiation of 'result_of' must always succeed.
(See the rationale at
Well, I have bad news. VC++7.1 and VC8 can't compile (1) nor (2). :-(
>> I introduce <boost/detail/functionN.hpp> at Boost.Accumulators,
>> which seems very cool.
> I looked for your file in the boost-sandbox cvs repository and
> couldn't find it. Could you send a link?
See the accumulators.zip in "Math - Numerics" directory at Boost Vault.
-- Shunsuke Sogame
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