chain.hpp

#pragma once
 
#include "../core/generator.hpp"
 
namespace z {
namespace util {
 
template <typename T, typename U, typename V>
core::generator<T, bool> chain(core::generator<T, U> &first, core::generator<T, V> &second) noexcept {
    return core::generator<T, bool>(false, [&first, &second](bool &first_exhausted) {
        if (!first_exhausted) {
            auto item = first.next();
            if (item.done) {
                first_exhausted = true;
            } else {
                return item;
            }
        }
 
        return second.next();
    });
}
 
} // namespace util
} // namespace z