initial commit

switch/switch.go

@@ -0,0 +1,54 @@
+package main
+
+import (
+	"fmt"
+	"time"
+)
+
+func main() {
+
+	// Basic switch default is optional
+	i := 2
+	fmt.Print("Write", i, " as ")
+	switch i {
+		case 1:
+			fmt.Println("one")
+		case 2:
+			fmt.Println("two")
+		case 3:
+			fmt.Println("three")
+	}
+
+	// Commas can seperate multiple expressions in the same case statement.
+	switch time.Now().Weekday() {
+		case time.Saturday, time.Sunday:
+			fmt.Println("It's the weekend")
+		default:
+			fmt.Println("It's a weekday")
+	}
+
+	//switch without an expression is a alternate way to express if/else logic
+	t := time.Now()
+	switch {
+		case t.Hour() < 12:
+			fmt.Println("It's before noon")
+		default:
+			fmt.Println("It's afte noon")
+	}
+
+	// a type switch compares types instead of values.
+	//you can use this to discorver the type of an interface value. 
+	whatAmI := func(i interface{}){
+		switch t := i.(type) {
+			case bool:
+				fmt.Println("I'm a bool")
+			case int:
+				fmt.Println("I'm an int")
+			default:
+				fmt.Printf("Don't know the type %T\n",t)
+		}
+	}
+	whatAmI(true)
+	whatAmI(1)
+	whatAmI("hey")
+}