go-function-as-type.go

package main

import "fmt"

// Define a function type called 'mathOperation'
type mathOperation func(int, int) int

// Define some functions that match the 'mathOperation' type
func add(a, b int) int {
    return a + b
}

func multiply(a, b int) int {
    return a * b
}

// Function that takes a 'mathOperation' as an argument
func calculate(a, b int, operation mathOperation) int {
    return operation(a, b)
}

func main() {
    // Using the function type to call 'add' or 'multiply'
    fmt.Println(calculate(3, 4, add))      // Outputs: 7
    fmt.Println(calculate(3, 4, multiply)) // Outputs: 12
}