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_Switch statements_ express conditionals across many branches.

	package main

	import (
	"fmt"
	"time"
	)

	func main() {

Here's a basic `switch`.	i := 2
	fmt.Print("Write ", i, " as ")	Write 2 as
	switch i {
	case 1:
	fmt.Println("one")
	case 2:
	fmt.Println("two")	Write 2 as two
	case 3:
	fmt.Println("three")
	}

You can use commas to separate multiple expressions in the same `case` statement. We use the optional `default` case in this example as well.	switch time.Now().Weekday() {
	case time.Saturday, time.Sunday:
	fmt.Println("It's the weekend")
	default:
	fmt.Println("It's a weekday")	It's a weekday
	}

`switch` without an expression is an alternate way to express if/else logic. Here we also show how the `case` expressions can be non-constants.	t := time.Now()
	switch {
	case t.Hour() < 12:
	fmt.Println("It's before noon")
	default:
	fmt.Println("It's after noon")	It's after noon
	}

A type `switch` compares types instead of values. You can use this to discover the type of an interface value. In this example, the variable `t` will have the type corresponding to its clause.	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 type %T\n", t)
	}
	}
	whatAmI(true)
	whatAmI(1)
	whatAmI("hey")
	}	I'm a bool I'm an int Don't know type string

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