anchor.diff:      }
   
   
  -  member this.TryFind(key:'K, direction:Lookup, [<Out>] result: byref<KeyValuePair<'K, 'V>>) = 
  -    let res() =
  +  member private this.TryFindTuple(key:'K, direction:Lookup) = 
  +    let tupleResult =
         let mutable kvp = Unchecked.defaultof<KeyValuePair<'K, 'V>>
           
         let hash = existingHash key
  
positive.code:           else
              ValueTuple<_,_>(false, kvp)
          | _ -> ValueTuple<_,_>(false, kvp) // LookupDirection.EQ
      let tupleResult = readLockIf &this.nextVersion &this.version this.isSynchronized res
      result <- tupleResult.Value2
      tupleResult.Value1
  
negative.code:             | Lookup.GT | Lookup.GE ->
                let hash = existingHash key
                let subKey = key
                let hasPivot, pivot = this.TryFindUnchecked(key, direction)
                if hasPivot then
                  if comparer.Compare(key, hash) = 0 && direction = Lookup.GE then
                    outerMap.RemoveMany(hash, Lookup.GE) // remove in one go
  