FizzBuzz iteratively and recursively https://play.golang.org/p/NAl_rTcCxe

fizzbuzz.go

// fizzbuzz see the goplayground for output
// https://play.golang.org/p/NAl_rTcCxe
package main

import (
	"fmt"
)

// recursiveFizzBuzz returns a string
// of every FizzBuzz output from the original
// input until 100 (which is Buzz)
func recursiveFizzBuzz(num int) string {
    if num > 100 {
        return "" // terminal condition
    }

    if num % 3 == 0 {
        fmt.Print("Fizz") // no newline
    }

    if num % 5 == 0 {
        fmt.Println("Buzz")
        return recursiveFizzBuzz(num+1)
    } 
    
    if num % 3 == 0 { // if Fizz was printed
        fmt.Println() // there won't be a newline
        return recursiveFizzBuzz(num+1)
    }

    fmt.Println(num) // neither fizz nor buzz

    return recursiveFizzBuzz(num+1)
}

// iterativeFizzBuzz returns a string
// of line seperated FizzBuzz values
// from 1 to 100.
func iterativeFizzBuzz() string {
    var result string // init empty string
    for i := 1; i < 101; i++ {
        fizz := i % 3 == 0
        buzz := i % 5 == 0
        if fizz {
            result += fmt.Sprint("Fizz")
        }

        if buzz {
            result += fmt.Sprintln("Buzz")
        } else if !fizz {
            result += fmt.Sprintln(i) // just the number
        } else { 
            // Fizz was printed without \n
            result += fmt.Sprint("\n")
        }
    }

    return result
}

func main() {
    fmt.Println(iterativeFizzBuzz())
    fmt.Println(recursiveFizzBuzz(1))
}