anchor.diff:          member p.MoveNext() = 
             let entered = enterLockIf syncRoot isSynchronized
             try
  -            if cursorVersion =  this.orderVersion then
  +            if cursorVersion = this.orderVersion then
                 if index < (this.size - 1) then
                   index <- index + 1
                   // TODO!! (perf) regular keys were supposed to speed up things, not to slow down by 50%! 
  
positive.code:       #if PRERELEASE
        // TODO why we check here if the method is named 'unchecked'?
        // (TODO clean this two comment lines) if uint32 index >= uint32 this.size then raise (ArgumentOutOfRangeException("index"))
        Trace.Assert(uint32 index >= uint32 this.size, "Index must be checked before calling GetPairByIndexUnchecked")
        #endif
        KeyValuePair(this.rkKeyAtIndex index, this.values.[index])
      else KeyValuePair(this.keys.[index], this.values.[index]) 
  
negative.code:   
    [<MethodImplAttribute(MethodImplOptions.AggressiveInlining)>]
    member private this.CompareToLast (k:'K) =
      if couldHaveRegularKeys && this.size > 1 then
        #if PRERELEASE
        Trace.Assert(not <| Unchecked.equals rkLast Unchecked.defaultof<'K>)
        #endif
        comparer.Compare(k, rkLast)
      else comparer.Compare(k, this.keys.[this.size-1])
  
  