Add future

Author: mortennobel

README.md

@@ -553,4 +553,21 @@ sharedMes = "ping";
 thread t1(pingPongFn, sharedMes); // start example with 3 concurrent threads
 thread t2(pingPongFn, "pong");
 thread t3(pingPongFn, "boing");
+```
+
+## `future` (thread support library)
+```cpp
+#include <future> // Include future
+function<int(int)> fib = // Create lambda function
+ [&](int i){
+ if (i <= 1){
+ return 1;
+ }
+ return fib(i-1) 
+ + fib(i-2);
+ };
+future<int> fut = // result of async function
+ async(launch::async, fib, 4); // start async function in other thread
+// do some other work 
+cout << fut.get(); // get result of async function. Wait if needed.
 ```