js 二维组数组装规格 无限级

function combination(arr) {
  var sarr = [[]];
  var result = [];
  for (var i = 0; i < arr.length; i++) {
    var tarr = [];
    for (var j = 0; j < sarr.length; j++){
      for (var k = 0; k < arr[i].length; k++){
        tarr.push(sarr[j].concat(arr[i][k]));
      }
    }
    sarr = tarr;
  }
  for(var m =0; m < sarr.length;m++) {
    result.push(sarr[m].join('.'));
  }
  return result;
}
var garr = [["a","b"],["1","2"],["红色","白色"],["大型","小型"]];
var result = combination(garr);
console.log(result);

//结果输出
[
    "a.1.红色.大型",
    "a.1.红色.小型",
    "a.1.白色.大型",
    "a.1.白色.小型",
    "a.2.红色.大型",
    "a.2.红色.小型",
    "a.2.白色.大型",
    "a.2.白色.小型",
    "b.1.红色.大型",
    "b.1.红色.小型",
    "b.1.白色.大型",
    "b.1.白色.小型",
    "b.2.红色.大型",
    "b.2.红色.小型",
    "b.2.白色.大型",
    "b.2.白色.小型"
]