imitating function overloading in go

func_overloading_golang.go

package main

import (
	"fmt"
)

func main() {
	// imitating func overloading in Go
	
	// this example uses this:
	// https://golang.org/doc/effective_go.html#interface_conversions

	// sum integers with the same function
	// output: 3
	fmt.Println(sum(1, 2))

	// sum float64s with the same function
	// output: 6.1
	fmt.Println(sum(3.7, 2.4))

	// exercise: should have a proper err logic instead of returning nil.
}


func sum(a interface{}, b interface{}) interface{} {
	switch a.(type) {
	// check for ints
	case int:
		if bint, ok := b.(int); !ok {
			return nil
		} else {
			aint, _ := a.(int)
			return sumInt(aint, bint)
		}

    // check for floats
	case float64:
		if bfloat, ok := b.(float64); !ok {
			return nil
		} else {
			afloat, _ := a.(float64)
			return sumFloat64(afloat, bfloat)
		}
	}
	return nil
}

func sumInt(a int, b int) int {
	return a + b
}

func sumFloat64(a float64, b float64) float64 {
	return a + b
}