vue3 computed详解
class ComputedRefImpl {
constructor(getter, _setter, isReadonly) {
this._setter = _setter;
this._dirty = true;
this.__v_isRef = true;
this.effect = effect(getter, {
lazy: true,
scheduler: () => {
if (!this._dirty) {
this._dirty = true;
trigger(toRaw(this), "set" /* SET */, 'value');
}
}
});
this["__v_isReadonly" /* IS_READONLY */] = isReadonly;
}
get value() {
// the computed ref may get wrapped by other proxies . readonly() #3376
const self = toRaw(this);
if (self._dirty) {
self._value = this.effect();
self._dirty = false;
}
track(self, "get" /* GET */, 'value');
return self._value;
}
set value(newValue) {
this._setter(newValue);
}
}