const branch = function(b) {
  return b.if ? b.then : b.else;
}

const fizzbuzz = function(num) {
  return branch({
    if: num % 3 === 0 && num % 5 === 0,
    then: 'fizzbuzz',
    else: branch({
        if: num % 3 === 0,
        then: 'fizz',
        else: branch({
          if: num % 5 === 0,
          then: 'buzz',
          else: num
        })
      })
  });
}

console.log(
  [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16].map(
    cv => fizzbuzz(cv)
  )
);

// [1, 2, "fizz", 4, "buzz", "fizz", 7, 8, "fizz", "buzz", 11, "fizz", 13, 14, "fizzbuzz", 16]