Method constructor

packages/reactivity/src/ref.ts:383–403

(
    private readonly _object: T,
    key: K,
    private readonly _defaultValue?: T[K],
  )

  private readonly _shallow: boolean

  constructor(
    private readonly _object: T,
    key: K,
    private readonly _defaultValue?: T[K],
  ) {
    this._key = (isSymbol(key) ? key : String(key)) as K
    this._raw = toRaw(_object)

    let shallow = true
    let obj = _object

    class="cm">// For an array with integer key, refs are not unwrapped
    if (!isArray(_object) || isSymbol(this._key) || !isIntegerKey(this._key)) {
      class="cm">// Otherwise, check each proxy layer for unwrapping
      do {
        shallow = !isProxy(obj) || isShallow(obj)
      } while (shallow && (obj = (obj as Target)[ReactiveFlags.RAW]))
    }

    this._shallow = shallow
  }

  get value() {
    let val = this._object[this._key]