anchor.diff:      member this.RegisterArchetype (archetype : 'w Archetype) =
           archetypes.Add (archetype.Id, archetype)
   
  -    member this.Iterate (compName, statement : Statement<'c, 's>) =
  +    member this.Iterate (compName, statement : Statement<'c, 's>) : 's -> 's =
           fun state ->
               let mutable state = state
               for archetypeEntry in archetypes do
  
positive.code:                     i <- inc i
              state
  
      member this.Iterate (compName, comp2Name, statement : Statement<'c, 'c2, 's>) =
          fun state ->
              let mutable state = state
              for archetypeEntry in archetypes do
  
negative.code:                     i <- inc i
              state
  
      member this.Iterate (compName, comp2Name, comp3Name, statement : Statement<'c, 'c2, 'c3, 's>) : 's -> 's =
          fun state ->
              let mutable state = state
              for archetypeEntry in archetypes do
  