The Three Dots In Golang...

Nice one ! Also consider example with simple under(lying) type

package main

import (
    . "fmt"
)

type under int

// Based on (but with underlying type) : @blog.harishdurga.com/the-three-dots-in-golang
// define ...rest like parameter for variadic functions
func Sum(nums ...under) under {
    var r under = 0
    for _, n := range nums {
        r += n
    }
    return under(r)
}

func main() {
    /* Println( Sum([]int{1,2,3}...) ) */// instead do:
    Println( Sum([]under{1,2,3}...) )
}