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Variables in Go

Variable Declaration & Initialization

// declare a variable first (with type), and then initialize it
var name string
name = "Deependu Jha"

// OR (declare and initialize in one line)
var name string = "Deependu Jha"

// OR (declare and initialize in one line with walrus operator)
name := "Deependu Jha" // walrus operator (declare and initialize in one line)

Variable Types

Type Description
bool Boolean type, can be true or false.
int Integer type, can be positive or negative.
int8, int16, int32, int64 Signed integer types, can be positive or negative.
uint8, uint16, uint32, uint64 Unsigned integer types, can only be positive.
float32, float64 Floating-point types, can be positive or negative.
string String type, can be empty.
[]byte Byte slice type, can be empty. 
import "fmt"

func main() {
    fmt.Print("Hello, World!\n") // print without newline
    fmt.Println("Hello, World!") // print with newline
    fmt.Printf("Hello, %s!", "World") // print with format
}

Log in Go

import "log"

func main() {
    log.Print("Hello, World!\n") // print without newline
    log.Println("Hello, World!") // print with newline
    log.Printf("Hello, %s!", "World") // print with format

    log.Fatal("Fatal error!") // logs and exits (os.exit(1))
    log.Fatalf("Fatal error! %s", "World") // logs and exits
    log.Panic("Panic error!") // logs and panics
}