arr.filter((item, index, arr) => arr.indexOf(item, 0) === index )

image.png

深拷贝

function deepClone(origin, target) {
      var target = target || {},
          toStr = Object.prototype.toString,
          tpyeArray = '[object Array]';
      for (key in origin) {
        if (origin.hasOwnProperty(key)) {
          if (typeof(origin[key]) === 'object' && origin[key] !== null) {
            toStr.call(origin[key]) === tpyeArray ? target[key] = [] : target[key] = {}
          } else {
            target[key] = origin[key]
          }
        }
      }
      return target
    }