diff --git a/test/async.cpp b/test/async.cpp
deleted file mode 100644
index f2ab1c4..0000000
--- a/test/async.cpp
+++ /dev/null
@@ -1,31 +0,0 @@
-#include <string>
-#include <future>
-#include <iostream>
-
-std::string copy_string(const std::string& s) {
-    return s;
-}
-
-int find_answer() {
-    throw std::runtime_error("hoge!");
-    return 1;
-}
-
-int main() {
-    std::string s("hello");
-    //auto f = std::async(std::launch::async, copy_string, std::cref(s));
-    //auto f = std::async(std::launch::async, copy_string, s);
-    auto f = std::async(std::launch::async, [&]() {
-            return copy_string(s);
-        });
-    s = "goodbye";
-    std::cout << f.get() << " world!\n";
-
-    auto g = std::async(std::launch::async, find_answer);
-    try {
-        g.get();
-    } catch(const std::runtime_error& e) {
-        std::cerr << "error: " << e.what() << std::endl;
-    }
-    return 0;
-}