নোট সমূহ

Hello World

A sample go program is show here.

package main

import "fmt"

func main() {
  message := greetMe("world")
  fmt.Println(message)
}

func greetMe(name string) string {
  return "Hello, " + name + "!"
}

Run the program as below:

$ go run hello.go

Variables

Normal Declaration:

var msg string
msg = "Hello"

Shortcut:

msg := "Hello"

Constants

const Phi = 1.618

Strings

str := "Hello"

Multiline string

str := `Multiline
string`

Numbers

Typical types

num := 3          // int
num := 3.         // float64
num := 3 + 4i     // complex128
num := byte('a')  // byte (alias for uint8)

Other Types

var u uint = 7        // uint (unsigned)
var p float32 = 22.7  // 32-bit float

Arrays

// var numbers [5]int
numbers := [...]int{0, 0, 0, 0, 0}

Pointers

func main () {
  b := *getPointer()
  fmt.Println("Value is", b)

func getPointer () (myPointer *int) {
  a := 234
  return &a

a := new(int)
*a = 234

Pointers point to a memory location of a variable. Go is fully garbage-collected.

Type Conversion

i := 2
f := float64(i)
u := uint(i)

Slice

slice := []int{2, 3, 4}

slice := []byte("Hello")

Condition

if day == "sunday" || day == "saturday" {
  rest()
} else if day == "monday" && isTired() {
  groan()
} else {
  work()
}

if _, err := doThing(); err != nil {
  fmt.Println("Uh oh")

Variable

NAME="John"
echo $NAME
echo "$NAME"
echo "${NAME}

Condition

if [[ -z "$string" ]]; then
  echo "String is empty"
elif [[ -n "$string" ]]; then
  echo "String is not empty"
fi