Sample

README.md

@@ -133,6 +133,33 @@ auto io_ = do_(
 io_.run();
 ```
 
+And we can also compose two STMs with `orElse`
+```c++
+// (limitedWithdraw2 acc1 acc2 amt) withdraws amt from acc1,
+// if acc1 has enough money, otherwise from acc2.
+// If neither has enough, it retries.
+constexpr auto limitedWithdraw2 = toFunc<> | [](Account acc1, Account acc2, Integer amt)
+{
+    return orElse | (limitedWithdrawSTM | acc1 | amt) | (limitedWithdrawSTM | acc2 | amt);
+};
+
+Id<Account> acc1, acc2;
+auto io_ = do_(
+    acc1 <= (atomically | (newTVar | Integer{100})),
+    acc2 <= (atomically | (newTVar | Integer{100})),
+    showAcc | "Left pocket" | acc1,
+    showAcc | "Right pocket" | acc2,
+    forkIO | (delayDeposit | acc2 | 1),
+    print | "Withdrawing $101 from either pocket...",
+    atomically | (limitedWithdraw2 | acc1 | acc2 | Integer{101}),
+    print | "Successful withdrawal!",
+    showAcc | "Left pocket" | acc1,
+    showAcc | "Right pocket" | acc2
+);
+
+io_.run();
+```
+
 ## Haskell vs Hspp (Incomplete list)
 
 | Haskell       | Hspp |