diff --git a/include/asyncio.hpp b/include/asyncio.hpp
index 813e0f4..e69de29 100644
--- a/include/asyncio.hpp
+++ b/include/asyncio.hpp
@@ -1,24 +0,0 @@
-#include <coroutine>
-#include <future>
-namespace zt{
-    template<class T>
-    struct Task:std::coroutine_handle<T>{
-        struct promise_type;
-        struct promise_type{
-            std::promise<T> promise_;
-            void return_value(T value){promise_.set_value(value);}
-            auto initial_suspend(){
-                return std::suspend_always{};
-            }
-            auto final_suspend()noexcept{
-                return std::suspend_always{};
-            }
-            auto get_return_object(){
-                return Task<T>::from_promise(*this);
-            }
-            void unhandled_exception(){
-                return;
-            }
-        };
-    };
-}
\ No newline at end of file
diff --git a/src/test1.cpp b/src/test1.cpp
index b4b3e9d..aa2849f 100644
--- a/src/test1.cpp
+++ b/src/test1.cpp
@@ -1,15 +1,60 @@
-#include <future>
+#include <cstdio>
+#include<coroutine>
+#include <ios>
 #include <iostream>
-#include <ostream>
-#include <coroutine>
-#include "asyncio.hpp"
+#include <source_location>
+#include <stdexcept>
+#include <type_traits>
 
-zt::Task<int> return0(){
-    std::println(std::cout,"return 0;");
+template<class T>
+struct Promise;
+
+template<class T>
+struct coroutine: std::coroutine_handle<Promise<T>>{
+    using promise_type = ::Promise<T>;
+};
+
+template<class T=void>
+struct Promise{
+    auto initial_suspend(){
+        std::cout<<__FUNCTION__<<'\n';
+        return std::suspend_always{};
+    }
+    auto final_suspend()noexcept{
+        std::cout<<__FUNCTION__<<'\n';
+        return std::suspend_always{};
+    }
+    void unhandled_exception(){
+        std::cout<<__FUNCTION__<<'\n';
+        throw std::runtime_error("unhandled exeception\n");
+    }
+    void return_value(const std::decay_t<T> &t){
+        std::cout<<__FUNCTION__<<' '<<t<<'\n';
+    }
+    coroutine<T> get_return_object(){
+        std::cout<<__FUNCTION__<<'\n';
+        return {coroutine<T>::from_promise(*this)};
+    }
+    auto yield_value(const std::decay_t<T> &t){
+        std::cout<<__FUNCTION__<<' '<<t<<'\n';
+        return std::suspend_always{};
+    }
+    
+    coroutine<T> h;
+};
+
+coroutine<int> test(){
+    std::cout<<"testing\n";
+    co_yield 1;
+    co_yield 2;
     co_return 0;
 }
 
 int main(){
-    auto ret =  return0();
-    ret.promise_type;
+    std::cout<<__FUNCTION__<<'\n';
+    auto handle = test();
+    while (!handle.done()) {
+        std::cout<<__FUNCTION__<<'\n';
+        handle.resume();
+    }
 }
\ No newline at end of file