anchor.diff:                  structures.CurrentLabel := currentContext.Value.Label
                   structures.CurrentN := currentContext.Value.Ast 
                   structures.CurrentR := structures.Dummy
  +                currentPath := currentContext.Value.Path
                   condition := false
               else 
                   stop := true  
  
positive.code:                         currentGSSNode
                          currentVertexInInput
                          pop
  
                      
          let control () =
               while not !stop do
  
negative.code:                             condition := false
                          | 
                              None _ -> 
                                  containsError !currentVertexInInput !structures.CurrentLabel !currentGSSNode !structures.CurrentN !currentPath
                                  
                      else 
                          let getIndex nTerm term = 
                              let mutable index = nTerm
  