random

greetings.go

@@ -2,6 +2,8 @@ package greetings
 
 import "fmt"
 import "errors"
+import "math/rand"
+import "time"
 
 // Hello returns a greeting for the named person.
 func Hello(name string) (string,error) {
@@ -10,8 +12,27 @@ func Hello(name string) (string,error) {
         return "", errors.New("empty name")
     }
     // Return a greeting that embeds the name in a message.
-    message := fmt.Sprintf("Hi, %v. Welcome!", name)
+    message := fmt.Sprintf(randomFormat(), name)
+    #    message := fmt.Sprintf("Hi, %v. Welcome!", name)
     return message, nil
 }
 
+// init sets initial values for variables used in the function.
+func init() {
+    rand.Seed(time.Now().UnixNano())
+}
 
+// randomFormat returns one of a set of greeting messages. The returned
+// message is selected at random.
+func randomFormat() string {
+    // A slice of message formats.
+    formats := []string{
+        "Hi, %v. Welcome!",
+        "Great to see you, %v!",
+        "Hail, %v! Well met!",
+    }
+
+    // Return a randomly selected message format by specifying
+    // a random index for the slice of formats.
+    return formats[rand.Intn(len(formats))]
+}