anchor.diff:      [<Test>]
       member test.``Classic case. Many brackets 1``() =
           let qGraph = new ParserInputGraph<_>()
  -        qGraph.AddVertexRange[0;1;2;3;4;5] |> ignore
  +        qGraph.AddVertexRange[0; 1; 2; 3; 4; 5] |> ignore
  +        // [caret]((2))
           qGraph.AddVerticesAndEdgeRange
               [
                   createEdge 0 1 (RNGLR.ParseSummator.LBRACE 0)
  
positive.code:     [<Test>]
      member test.``Abstract case. Two parentheses``() =
          let qGraph = new ParserInputGraph<_>()
          qGraph.AddVertexRange[0;1;2;3] |> ignore
          qGraph.AddVerticesAndEdgeRange
              [createEdge 0 1 (RNGLR.ParseSummator.LBRACE 0)
               createEdge 1 2 (RNGLR.ParseSummator.NUMBER 1)
               createEdge 2 3 (RNGLR.ParseSummator.RBRACE 2)
               createEdge 2 3 (RNGLR.ParseSummator.RBRACE 3)
               ] |> ignore
  
          let result = (new Parser<_>()).Parse  RNGLR.ParseSummator.buildAstAbstract qGraph
  
negative.code:             let pairTokens = other.FindAllPair leftBraceNumber rightBraceNumber 0 true tokToNumber tokToPos
  
              printfn "%d pair(s) was found" pairTokens.Count
              Assert.AreEqual (2, pairTokens.Count, "Error: expected two pairs")
              
              let expectedValues = [|3; 4|]
              
              let actualValues = 
                  pairTokens 
  