anchor.diff:          member nodes.exist f = 
               if nodes.fst <> null 
               then 
  -                if f nodes.fst then true
  +                if f nodes.fst 
  +                then true
                   else 
                       if nodes.snd <> null 
                       then 
                           if f nodes.snd then true
                           else
                               if nodes.other <> null 
  -                            then Array.exists (fun node -> f node) nodes.other
  +                            then nodes.other |> Array.exists f
                               else false
                       else false
               else false
  
positive.code: 
          let containsRange number = 
              tokenToPos tokens.[number]
              |> Seq.exists (fun range -> range = now)
  
          let rec handleFamily (family : OtherFamily) = 
              family.nodes.doForAll 
  
negative.code:                     let otherChildren = 
                          if ast.other = null
                          then null
                          else ast.other |> Array.map processFamily
  
                      let newAST = new OtherAST (fstChild, otherChildren)
                      dict.Add (ast, newAST)
  