message: feature: add field "extra" on element to mount some extra values and enable "merge" to "extra" in "el.attr"
diff: @@ -232,6 +232,8 @@ export interface ElementProps extends Partial<ElementEventHandlerProps> {
  clipPath?: Path
  drift?: Element['drift']
  + extra?: Dictionary<unknown>
  +
  // For echarts animation.
  anid?: string
  }
  @@ -361,6 +363,8 @@ class Element<Props extends ElementProps = ElementProps> {
  */
  anid: string
  + extra: Dictionary<unknown>
  +
  currentStates?: string[] = []
  // prevStates is for storager in echarts.
  prevStates?: string[]
  @@ -648,6 +652,10 @@ class Element<Props extends ElementProps = ElementProps> {
  else if (key === 'clipPath') {
  this.setClipPath(value as Path);
  }
  + else if (key === 'extra') {
  + this.extra = this.extra || {};
  + extend(this.extra, value);
  + }
  else {
  (this as any)[key] = value;
  }
  