I have an array of objects:

let cars = [
  {
    "color": "purple",
    "type": "minivan",
    "registration": new Date('2017-01-03'),
    "capacity": 7
  },
  {
    "color": "red",
    "type": "station wagon",
    "registration": new Date('2018-03-03'),
    "capacity": 5
  },
  {
    ...
  },
  ...
]

the object with purple color is in 0 index and the object with red color in 1 index. How can I change the object with red color to be in 0 index and purple in 1 using only their index, not attributes?