Projectile Hit/End trigger

I have a centralized skill system (i.e. different items use the same skill). An example of a centralized skill is a bow shoot skill:

BowShoot:
  Skills:
  - projectile{etc} @forward{f=100}

However, what if you want a bow with an effect that applies when the projectile hits an enemy?

Currently, you would have to make a custom shoot skill just for that item. However, a better way would be to do this:

CoolBow:
  Id: BOW
  Skills:
  - skill{s=BowShoot} ~onSwing
  - message{m='Test'} ~onProjectileEnd
  - message{m='Hit!'} ~onProjectileHit