TweenVisitor<T> typedef

Tween<T> TweenVisitor (Tween<T> tween, T targetValue, TweenConstructor<T> constructor)

Signature for callbacks passed to AnimatedWidgetBaseState.forEachTween.

Implementation 

typedef TweenVisitor<T> = Tween<T> Function(Tween<T> tween, T targetValue, TweenConstructor<T> constructor);