anchor.diff:                      // Add this new DFA state to the set of unvisited states
                       // targeted by transitions from the current DFA state.
                       let unvisitedTransitionTargets =
  -                        Set.add newDfaState unvisitedTransitionTargets
  +                        TagSet.add newDfaState unvisitedTransitionTargets
   
                       newDfaState,
                       unvisitedTransitionTargets,
  
positive.code:         dfaState, compilationState
  
  //
  let private transitions regularVector (transitionsFromCurrentDfaState, unvisitedTransitionTargets, compilationState) derivativeClass =
      // Ignore empty derivative classes.
      if CharSet.isEmpty derivativeClass then
          transitionsFromCurrentDfaState,
  
negative.code: //
  let rec private createDfa pending compilationState =
      // If there are no more pending states, we're finished compiling.
      if TagSet.isEmpty pending then
          compilationState
      else
          //
          let currentState = TagSet.minElement pending
          let pending = TagSet.remove currentState pending
  
          //
          let regularVector = CompilationState.getRegularVector currentState compilationState
  