Overview

Constant Variable cannot be reassigned after its declaration as it is constant and its value cannot change. If you try to reassign to a constant variable then it will raise a compilation error.

Example

For example below code will raise a compilation error

package main
func main() {
    const a int = 8
    a = 9
}

Output

main.go:5:4: cannot assign to a

In the above program we created a constant first

const a int = 8

Then we try to assign a new value 9 to constant a, hence it raises a compilation error as constant once declared cannot be reassigned.