asyncpp/include/asyncpp/core/future/and_then.h

#pragma once

#include <memory>

namespace asyncpp {
namespace __future {

    template<
        typename T_future,
        typename T_lambda>
    struct and_then_impl
    {
    public:
        using lambda_type           = T_lambda;
        using outer_future_type     = T_future;
        using outer_value_type      = typename outer_future_type::value_type;
        using inner_future_type     = decltype(as_future(std::declval<lambda_type>()(std::declval<outer_value_type>())));
        using inner_future_type_ptr = std::unique_ptr<inner_future_type>;

    public:
        lambda_type             lambda;
        outer_future_type       outer;
        inner_future_type_ptr   inner;

    public:
        /**
         * @brief Constructor.
         */
        template<
            typename X_future,
            typename X_lambda>
        inline and_then_impl(
            X_future&& p_outer,
            X_lambda&& p_lambda);
    };

} }