Re: [boost] GSoC: Enforcing Code Feature Requirements

Subject: Re: [boost] GSoC: Enforcing Code Feature Requirements
From: Joel Falcou (joel.falcou_at_[hidden])
Date: 2010-03-31 08:01:52

> Joel, maybe you can elaborate how the Concept/SFINAE approach manages with this problem.

Sure,

in my head, we can define Concepts callee ThreadSafe, ExceptionSafe etc 
and just use BOOST_CONCEPT_REQUIRE on those (or the real C++0x concept 
maps) and have Concept Violation error when you try to call one function 
with improper settings. Then, IIRC there was planned to have SFINAE 
based on concept so we cna alos have function prunning (ie nice 'no such 
function f() defined' inthose case.

Using BOOST.CC, I already do that for parallel computing enforcement: i 
have a type traits that I can specialize per obejct or function type 
basis and the concept class just check for this concept then I write:

template<class F,class A>
BOOST_CONCEPT_REQUIRE( (CalalbleObject<F>)(DataParallel<F>)
                      , std::vector<boost::result_of<F(A)>::type>
                     )
map( F f, std::vector<A>);

if f is not a CallableObjec supporting data-parallelism (here I just 
check that is_dataparallel<F>::value is true) then the function is not 
permitted.

Such a mechanism can be applied to what's describe in the article, or am 
I mistaken ?