Re: [boost] Yap's formal review is starting now!

Subject: Re: [boost] Yap's formal review is starting now!
From: Peter Dimov (lists_at_[hidden])
Date: 2018-02-16 18:29:30

Steven Watanabe wrote:

> > As is, it isn't, because MSVC 2017 can't even include hana.hpp at 
> > present, let alone make any use of it.
>
> It took me about 5 minutes to fix that.

The implied argument being that it's better to fix Hana, or at least those 
parts of it that Yap uses, to compile under MSVC instead?

I still don't think it's better to have the user write

template <typename Expr1, typename Expr2, typename Expr3>
decltype(auto) transform_expression (
    boost::yap::expression<
        boost::yap::expr_kind::plus,
        boost::hana::tuple<
            boost::yap::expression<
                boost::yap::expr_kind::multiplies,
                boost::hana::tuple<
                    Expr1,
                    Expr2
                >
            >,
            Expr3
        >
    > const & expr
)

instead of

template <typename Expr1, typename Expr2, typename Expr3>
decltype(auto) transform_expression (
    boost::yap::expression<
        boost::yap::expr_kind::plus,
        std::tuple<
            boost::yap::expression<
                boost::yap::expr_kind::multiplies,
                std::tuple<
                    Expr1,
                    Expr2
                >
            >,
            Expr3
        >
    > const & expr
)

or

template <typename Expr1, typename Expr2, typename Expr3>
decltype(auto) transform_expression (
    boost::yap::expression<
        boost::yap::expr_kind::plus,
        boost::yap::expression<
            boost::yap::expr_kind::multiplies,
            Expr1,
            Expr2
        >,
        Expr3
    > const & expr
)

but, whatever.