Re: Boost.Lambda2 usage

From: Emil Dotchevski (emildotchevski_at_[hidden])
Date: 2021-03-28 19:26:22

On Sun, Mar 28, 2021 at 10:50 AM Barry Revzin via Boost <
boost_at_[hidden]> wrote:
> Second, this library has name lookup issues. Here's a reduced example (
> https://godbolt.org/z/z8oEqnTnG):
>
> #include <
>
https://raw.githubusercontent.com/pdimov/lambda2/develop/include/boost/lambda2/lambda2.hpp
> >
>
> namespace N {
>     struct Irrelevant { };
>     void operator+(Irrelevant, Irrelevant);
>
>     int plus_one(int i) {
>         using namespace boost::lambda2;
>         return (_1 + 1)(i);
>     }
> }

To successfully compile, this has to be:

int plus_one(int i) {
    using namespace std::placeholders;
    using boost::lambda2::operator+;
    return (_1 + 1)(i);
}

Note that it will not work if you say "using namespace boost::lambda2", you
have to bring in each individual operator you need.