Go — Operators

Arithmetic operators

package main

import "fmt"

func main() {
    a, b := 10, 3

    fmt.Println("Add:", a+b)   // 13
    fmt.Println("Sub:", a-b)   // 7
    fmt.Println("Mul:", a*b)   // 30
    fmt.Println("Div:", a/b)   // 3 (integer division)
    fmt.Println("Mod:", a%b)   // 1
}

Increment and decrement

x := 5
x++ // 6
x-- // 5

Comparison operators

fmt.Println(5 == 5)  // true
fmt.Println(5 != 3)  // true
fmt.Println(5 > 3)   // true
fmt.Println(5 < 3)   // false
fmt.Println(5 >= 5)  // true
fmt.Println(5 <= 3)  // false

Logical operators

a, b := true, false

fmt.Println(a && b)  // false (AND)
fmt.Println(a || b)  // true  (OR)
fmt.Println(!a)      // false (NOT)

Bitwise operators

a, b := 0b1010, 0b1100 // 10, 12

fmt.Printf("AND: %b\n", a&b)   // 1000 (8)
fmt.Printf("OR:  %b\n", a|b)   // 1110 (14)
fmt.Printf("XOR: %b\n", a^b)   // 0110 (6)
fmt.Printf("NOT: %b\n", ^a)     // ...
fmt.Printf("Left:  %b\n", a<<1) // 10100 (20)
fmt.Printf("Right: %b\n", a>>1) // 101 (5)

Assignment operators

x := 10
x += 5   // 15
x -= 3   // 12
x *= 2   // 24
x /= 4   // 6
x %= 4   // 2

Address and dereference

x := 10
p := &x    // Address of x
fmt.Println(*p) // 10 (dereference)
*p = 20    // Modify x through pointer
fmt.Println(x)  // 20

Channel operators

ch := make(chan int, 1)

// Send
ch <- 42

// Receive
value := <-ch

// Close
close(ch)

Type assertion

var i interface{} = "hello"

// Type assertion
s, ok := i.(string)
fmt.Println(s, ok) // hello true

// Type switch
switch v := i.(type) {
case int:
    fmt.Println("int:", v)
case string:
    fmt.Println("string:", v)
}

Operator precedence

Precedence	Operators
5	*, /, %, <<, >>, &, &^
4	+, -, |, ^
3	==, !=, <, <=, >, >=
2	&&
1	||

Mini Practice

Write Go code that:

1. Demonstrates all arithmetic operators
2. Uses bitwise operators for flags
3. Shows pointer address and dereference
4. Uses a channel with send and receive operators

Up Next

In the next lesson, you'll learn about Strings — working with text in Go.