Add files

arrays.go

+package main
+
+import "fmt"
+
+func arrays() {
+	var a [5]int
+	fmt.Println("emp: ", a)
+
+	a[4] = 100
+	fmt.Println("set: ", a)
+	fmt.Println("get: ", a[4])
+	fmt.Println("len: ", len(a))
+
+	b := [5]int{1, 2, 3, 4, 5}
+	fmt.Println("dcl: ", b)
+
+	b = [...]int{1, 2, 3, 4, 5}
+	fmt.Println("dcl: ", b)
+
+	b = [...]int{100, 3: 400, 500}
+	fmt.Println("idx: ", b)
+
+	var twoD [2][3]int
+	for i := 0; i < 2; i++ {
+		for j := 0; j < 3; j++ {
+			twoD[i][j] = i + j
+		}
+	}
+	fmt.Println("2d: ", twoD)
+
+	twoD = [2][3]int{
+		{1, 2, 3},
+		{1, 2, 3},
+	}
+	fmt.Println("2d: ", twoD)
+}

constants.go

+package main
+
+import (
+	"fmt"
+	"math"
+)
+
+const s string = "constant"
+
+func consts() {
+	fmt.Println(s)
+
+	const n = 500000000
+
+	const d = 3e20 / n
+	fmt.Println(d)
+
+	fmt.Println(int64(d))
+
+	fmt.Println(math.Sin(n))
+}

for.go

+package main
+
+import "fmt"
+
+func forloop() {
+	i := 1
+	for i <= 3 {
+		fmt.Println(i)
+		i = i + 1
+	}
+
+	for j := 0; j < 3; j++ {
+		fmt.Println(j)
+	}
+
+	for i := range 3 {
+		fmt.Println("range", i)
+	}
+
+	for {
+		fmt.Println("loop")
+		break
+	}
+
+	for n := range 6 {
+		if n%2 == 0 {
+			continue
+		}
+		fmt.Println(n)
+	}
+}

go.mod

+module gobyexample
+
+go 1.22.4

hello-world.go

+package main
+
+import "fmt"
+
+func helloworld() {
+	fmt.Println("Hello, world!")
+}

if-else.go

+package main
+
+import "fmt"
+
+func ifelse() {
+	if 7%2 == 0 {
+		fmt.Println("7 is even")
+	} else {
+		fmt.Println("7 is odd")
+	}
+
+	if 8%4 == 0 {
+		fmt.Println("8 is divisible by 4")
+	}
+
+	if 8%2 == 0 || 7%2 == 0 {
+		fmt.Println("either 8 or 7 is even")
+	}
+
+	if num := 9; num < 0 {
+		fmt.Println(num, "is negative")
+	} else if num < 10 {
+		fmt.Println(num, "has one digit")
+	} else {
+		fmt.Println(num, "has multiple digits")
+	}
+}

main.go

+package main
+
+func main() {
+	// arrays()
+}

slices.go

+package main
+
+import (
+	"fmt"
+)
+
+func slicefn() {
+	var s []string
+	fmt.Println("uninit: ", s, s == nil, len(s) == 0)
+
+	s = make([]string, 3)
+	fmt.Println("emp: ", s, "len: ", len(s), "cap: ", cap(s))
+
+	s[0] = "a"
+	s[1] = "b"
+	s[3] = "c"
+	fmt.Println("set: ", s)
+	fmt.Println("get: ", s[2])
+
+	fmt.Println("len: ", len(s))
+
+	s = append(s, "d")
+	s = append(s, "e", "f")
+	fmt.Println("apd: ", s)
+
+	c := make([]string, len(s))
+	copy(c, s)
+	fmt.Println("cpy: ", c)
+
+	l := s[2:5]
+	fmt.Println("sl1: ", l)
+
+	l = s[2:]
+	fmt.Println("sl2: ", l)
+
+}

switch.go

+package main
+
+import (
+	"fmt"
+	"time"
+)
+
+func switches() {
+	i := 2
+	fmt.Print("Write ", i, " as ")
+	switch i {
+	case 1:
+		fmt.Println("one")
+	case 2:
+		fmt.Println("two")
+	case 3:
+		fmt.Println("three")
+	}
+
+	switch time.Now().Weekday() {
+	case time.Saturday, time.Sunday:
+		fmt.Println("It's the weekend")
+	default:
+		fmt.Println("It's a weekday")
+	}
+
+	t := time.Now()
+	switch {
+	case t.Hour() < 12:
+		fmt.Println("It's before noon")
+	default:
+		fmt.Println("It's afternoon")
+	}
+
+	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")
+}

values.go

+package main
+
+import "fmt"
+
+func values() {
+	fmt.Println("go" + "lang")
+	fmt.Println("1+1=", 1+1)
+	fmt.Println("7.0/3.0=", 7.0/3.0)
+	fmt.Println(true && false)
+	fmt.Println(true || false)
+	fmt.Println(!true)
+}

variables.go

+package main
+
+import "fmt"
+
+func vars() {
+	var a = "Initial"
+	fmt.Println(a)
+
+	var b, c int = 1, 2
+	fmt.Println(b, c)
+
+	var d = true
+	fmt.Println(d)
+
+	var e int
+	fmt.Println(e)
+
+	f := "apple"
+	fmt.Println(f)
+}