lean into examples

examples/synchronization/synchronization.go

@@ -0,0 +1,30 @@
+// We can use channels to synchronize execution
+// accross goroutines. Here's an example of waiting
+// for another goroutine to finish.
+
+package main
+
+import "fmt"
+import "time"
+
+// The `done` channel will be used for
+// synchronization.
+func worker(done chan<- bool) {
+    fmt.Print("Working...")
+    time.Sleep(time.Second)
+    fmt.Println(" done")
+
+    // Send a value to notify that the work is done.
+    done <- true
+}
+
+func main() {
+    // Start a worker goroutine, give it the channel to
+    // notify on.
+    done := make(chan bool, 1)
+    go worker(done)
+
+    // Block until we can receive a value from the worker
+    // over the channel.
+    <-done
+}

examples/synchronization/synchronization.sh

@@ -0,0 +1,6 @@
+$ go run synchronization.go      
+Working... done                  
+
+# If you commented out the `<- done` line, the
+# program would exit before the `worker` even
+# started.