Go 언어에서 제어문

package main

import (
	"fmt"
)

func main() {
	friendNames := []string{"yoshi", "mario", "peach", "bowser", "luigi"}

	// local copy friendNames to value within loop
    for _, value := range friendNames {
		fmt.Printf("the value at index %v\n", value)
		value = "new string"
	}
}

// 결과
//
// the value at index yoshi
// the value at index mario
// the value at index peach
// the value at index bowser
// the value at index luigi​

package main

import (
	"fmt"
)

func main() {
	switch i := 1; i {
	case 1:
		fmt.Println("one")
	case 2:
		fmt.Println("two")
	default:
		fmt.Println("another number")
	}

	switch i := 1 + 1; i {
	case 1:
		fmt.Println("one")
	case 2:
		fmt.Println("two")
	default:
		fmt.Println("another number")
	}

	var i interface{} = 1
	switch i.(type) {
	case int:
		fmt.Println("i is an int")
	case float64:
		fmt.Println("i is an floate64")
	case string:
		fmt.Println("i is string")
	default:
		fmt.Println("i is another type")
	}

	var j interface{} = [3]int{}
	switch j.(type) {
	case int:
		fmt.Println("j is an int")
	case float64:
		fmt.Println("j is an floate64")
	case string:
		fmt.Println("j is string")
	default:
		fmt.Println("j is another type")
	}
}

// 결과
//
// one
// two
// i is an int
// j is another type

 

---

package main

import (
	"fmt"
)

func main() {
	for i, j := 0, 0; i < 5; i, j = i+1, j+1 {
		// for i, j := 0, 0; i < 5; i, j = i++, j++ { // error
		fmt.Println("i:", i, "j:", j)
	}

	fmt.Println("==========")

	l := 0
	for ; l < 5; l++ {
		fmt.Println(l)
	}
	fmt.Println(l)

	fmt.Println("==========")

	// infinite for loop
	k := 0
	for {
		if k == 10 {
			break
		}
		k++
	}

	fmt.Println("k:", k)

	fmt.Println("==========")

	d := []int{1, 2, 3}
	for k, v := range d {
		fmt.Println("key:", k, "value:", v)
	}
}

// 결과
//
// i: 0 j: 0
// i: 1 j: 1
// i: 2 j: 2
// i: 3 j: 3
// i: 4 j: 4
// ==========
// 0
// 1
// 2
// 3
// 4
// 5
// ==========
// k: 10
// ==========
// key: 0 value: 1
// key: 1 value: 2
// key: 2 value: 3

---

package main

import (
	"fmt"
)

func main() {

	// FizzBuzz
	for i := 0; i <= 100; i++ {
		if i%15 == 0 {
			fmt.Println("FizzBuzz")
		} else if i%3 == 0 {
			fmt.Println("Fizz")
		} else if i%5 == 0 {
			fmt.Println("Buzz")
		} else {
			fmt.Println(i)
		}
	}
}

// 결과
//
// FizzBuzz
// 1
// 2
// Fizz
// 4
// Buzz
// ...

---

package main

import (
	"fmt"
)

func main() {
	friendNames := []string{"yoshi", "mario", "peach", "bowser", "luigi"}

	// local copy friendNames to value within loop
	for _, value := range friendNames {
		fmt.Printf("the value at index %v\n", value)
		value = "new string"
	}
}

// 결과
//
// the value at index yoshi
// the value at index mario
// the value at index peach
// the value at index bowser
// the value at index luigi