fizzbuzz-funcs.go

package main

import "fmt"

type Rule func(int) string

func filter(div int, tag string) Rule {
	return func(n int) string {
		if n%div == 0 {
			return tag
		}
		return ""
	}
}

func apply(rules []Rule, n int) interface{} {
	res := ""
	for _, rule := range rules {
		res += rule(n)
	}
	if len(res) > 0 {
		return res
	}
	return n
}

func main() {
	var rules = []Rule{
		filter(3, "Fizz"),
		filter(5, "Buzz"),
		filter(9, "Boom"),
	}
	for i := 1; i <= 45; i++ {
		fmt.Println(apply(rules, i))
	}
}

Live code - http://play.golang.org/p/r3ZmRZheQl