add ex088 async 5 await

build.zig

@@ -430,6 +430,10 @@ const exercises = [_]Exercise{
         .main_file = "087_async4.zig",
         .output = "1 2 3 4 5",
     },
+    .{
+        .main_file = "088_async5.zig",
+        .output = "Example Title.",
+    },
 };
 
 /// Check the zig version to make sure it can compile the examples properly.

exercises/088_async5.zig

@@ -0,0 +1,47 @@
+//
+// Sure, we can solve our async value problem with a global
+// variable. But this hardly seems like an ideal solution.
+//
+// So how do we REALLY get return values from async functions?
+//
+// The 'await' keyword waits for an async function to complete
+// and then captures its return value.
+//
+//     fn foo() u32 {
+//         return 5;
+//     }
+//
+//    var foo_frame = async foo(); // invoke and get frame
+//    var value = await foo_frame; // await result using frame
+//
+// The above example is just a silly way to call foo() and get 5
+// back. But if foo() did something more interesting such as wait
+// for a network response to get that 5, our code would pause
+// until the value was ready.
+//
+// As you can see, async/await basically splits a function call
+// into two parts:
+//
+//    1. Invoke the function ('async')
+//    2. Getting the return value ('await')
+//
+// Also notice that a 'suspend' keyword does NOT need to exist in
+// a function to be called in an async context.
+//
+// Please use 'await' to get the string returned by
+// getPageTitle().
+//
+const print = @import("std").debug.print;
+
+pub fn main() void {
+    var myframe = async getPageTitle("http://example.com");
+
+    var value = ???
+
+    print("{s}\n", .{value});
+}
+
+fn getPageTitle(url: []const u8) []const u8 {
+    // Please PRETEND this is actually making a network request.
+    return "Example Title.";
+}

patches/patches/088_async5.patch

@@ -0,0 +1,4 @@
+39c39
+<     var value = ???
+---
+>     var value = await myframe;