Chaining alts together to transition effects in SCL

Sprite effects in SCL are called Alterations because they alter the sprite in some way. When an alteration completes an event can be fired for which you can instruct SCL to do something else. That something else can be either to run a routine or to apply one or more alterations. Being able to apply a new alteration when an alteration completes allows for making a chain of alterations.
Anonymous alterations are alterations that are not given a name but are defined within the completion event.
Example:
create sprite from 2.png as whatever
  having alt=(sub // use 'sub' to embed definition. The alteration is unnamed.
    create slide
      where direction=0 distance=50
    end)
end

In the example below (which you can run in the develop studio scratchpad) a sprite is moved around using a chain of alts. The first alteration requires a name, FirstSlide, so that the last alteration can refer back it to restart the sequence.
create sprite from 2.png as whatever
  having alt=(sub
    create slide as FirstSlide // named so we can re-call it
      where direction=0 distance=50 completion=(sub
    create slide
      where direction=270 distance=50 completion=(sub
    create rotation
      where speed=600 distance=720 completion=(sub
    create translation
      where x=0 y=0 completion=FirstSlide
    end) end) end) end)
end
create routine as Start launch whatever end