code: function concatArgs(...args) {
    const ret = [];
    args.forEach((arg) => {
      if (isSequence(arg)) {
        for (let j = 0; j < arg.length; j++) {
          ret.push(arg[j]);
        }
      } else {
        ret.push(arg);
      }
    });
    return ret;
  }
docs: Concatenates all `arguments` into a single array. Each argument can be either
  a single element or a sequence, which has a `length` property and supports
  element retrieval via sequence[ix].
  
  > concatArgs(1, [2, 3], new Buffer([4,5]), new Uint8Array([6, 7]));
  [1,2,3,4,5,6,7]
  
  @return {Array} - concatenated arguments