Нестандартный интерпретатор арифметического выражения - VB

Option Explicit
Private Sub cmdCOM_Click()
    b = True
    Ti = txtT.Text
    Call Main(Ti)
    frmG.Caption = Str(All)
End Sub
 
Private Sub txtT_Change()
    Dim n As Integer
    Ti = txtT.Text
    n = Ccc(Ti)
    cmdCOM.BackColor = _
    Switch(n = 2, vbRed, n = 1, vbYellow, True, vbGreen)
End Sub

Option Explicit
Option Base 1
    Public i%, j%, ii%, dll%, c1%, c2%, cc%
    Public Xx!, Yy!
    Public Ti As String
    Public asd(100) As String
    Public b As Boolean, All!
 
Public Sub Main(Tu As String)
    If Tu = "" Then Exit Sub
    If b Then
        Call Cubo(Tu, asd())
        For i = 2 To 100
            If asd(i) = " " Then
                dll = i: Exit For
            End If
        Next i
        b = False
        Xx = 1
        Yy = 2
    End If
    c2 = 0
    For i = 1 To dll
        If asd(i) = ")" Then
            c2 = i: GoTo 100
        End If
    Next i
                         
    If c2 = 0 Then            ' Скобок НЕТ - Вычисления окончены!!
        All = ini(asd(2))
        Exit Sub
    End If
100:
    For i = c2 - 2 To 1 Step -1
        If asd(i) = "(" Then
            c1 = i: Exit For
        End If
    Next i
    Call Mai2(asd())
    Call Main(Tu)
End Sub
 
Private Sub Mai2(fog() As String)
    Dim n As Integer, s As String
    
    fog(c1) = " "                    ' Долой скобки!!
    fog(c2) = " "
                                                ' Унарный минус (~)
    For i = c1 + 1 To c2 - 1
        If fog(i) = "~" Then
            fog(i) = Str(-ini(fog(i + 1)))
            Call Sdv1(i, c2)
            i = i - 1
        End If
    Next i
                                            ' Умножение и деление
    For i = c1 + 1 To c2 - 1
        If fog(i) = "*" Then
            fog(i - 1) = Str(ini(fog(i - 1)) * ini(fog(i + 1)))
            Call Sdv2(i, c2)
            i = i - 2
        ElseIf fog(i) = "/" Then
            If ini(fog(i + 1)) = 0 Then
                fog(i - 1) = "1"
            Else
                fog(i - 1) = Str(ini(fog(i - 1)) / ini(fog(i + 1)))
            End If
            Call Sdv2(i, c2)
            i = i - 2
        End If
    Next i
                                           ' Сложение и вычитание
    For i = c1 + 1 To c2 - 1
        If fog(i) = "+" Then
            fog(i - 1) = Str(ini(fog(i - 1)) + ini(fog(i + 1)))
            Call Sdv2(i, c2)
            i = i - 2
        ElseIf fog(i) = "-" Then
            fog(i - 1) = Str(ini(fog(i - 1)) - ini(fog(i + 1)))
            Call Sdv2(i, c2)
            i = i - 2
        End If
    Next i
    
    Select Case fog(c1 - 1)
        Case "s": fog(c1 - 1) = SStr(Sin(ini(fog(c1 + 1))))
        Case "c": fog(c1 - 1) = SStr(Cos(ini(fog(c1 + 1))))
        Case "m": fog(c1 - 1) = SStr(Abs(ini(fog(c1 + 1))))
        Case "e": fog(c1 - 1) = fog(c1 + 1)
    End Select
    
    cc = c2 - c1 + 1
    For i = c1 To dll - cc
        fog(i) = fog(i + cc)
    Next i
    dll = dll - cc
End Sub
                        ' Преобразует строку в массив
Private Sub Cubo(ByVal Tu2 As String, mn() As String)
    Dim k As Integer, dol As Integer
    Dim R As String, R1 As String
                                
    Tu2 = " " + Tu2 + " "
    dol = Len(Tu2)
    For i = 1 To dol
        R = Mid(Tu2, i, 1)
        R1 = Mid(Tu2, i + 1, 1)
        If Not Func(R) And (R1 = "(") Then
            Tu2 = Left(Tu2, i) + "e" + Right(Tu2, dol - i)
        End If
        R = Mid(Tu2, i, 1)
        R1 = Mid(Tu2, i + 1, 1)
        If ((R = "(") Or (R = " ")) And R1 = "-" Then
            Mid(Tu2, i + 1, 1) = "~"
        End If
        dol = Len(Tu2)
    Next i
    Tu2 = Trim(Tu2)
    Tu2 = " e(" + Tu2 + ") "
   
                                  ' ==============================
    Erase mn
    dol = Len(Tu2): k = 1                'k - Индекс массива
    i = 0
    Do
        i = i + 1
        R = Mid(Tu2, i, 1)
      
        If Not Ciff(R) Then
            mn(k) = R: k = k + 1: GoTo 100
        End If
                                                       
        If Ciff(R) Then
            mn(k) = R
            R1 = Mid(Tu2, i + 1, 1)
            j = 1
            Do While Ciff(R1)
                mn(k) = mn(k) + R1
                 j = j + 1
                R1 = Mid(Tu2, i + j, 1)
            Loop
            i = i + j - 1
            k = k + 1: GoTo 100
        End If
100:
    Loop Until i >= dol
End Sub
 
Private Function SStr(s As Single) As String
    SStr = LTrim(Str(s))
End Function
 
Private Sub Sdv1(c0%, c2%)
    For j = c0 To c2 - 2
        asd(j + 1) = asd(j + 2)
    Next j
    asd(c2) = " "
End Sub
 
Private Sub Sdv2(c0%, c2%)
    For j = c0 To c2 - 2
        asd(j) = asd(j + 2)
    Next j
    asd(c2) = " "
    asd(c2 - 1) = " "
End Sub
 
Private Function ini(Tex As String) As Single
        Select Case Tex
            Case "x": ini = Xx
            Case "y": ini = Yy
            Case Else
                ini = Val(Tex)
        End Select
End Function
 
Public Function Ccc(Tex As String) As Integer
    Dim R As String, ll%
    Ccc = 0
    ii = 0
    ll = Len(Tex)
    For i = 1 To ll
         R = Mid(Tex, i, 1)
         If R = "(" Then
            ii = ii + 1
         ElseIf R = ")" Then
            ii = ii - 1
         End If
    Next i
    Ccc = Switch(ii < 0, 2, ii > 0, 1, True, 0)
End Function
 
Public Function Func(FF As String) As Boolean
    Func = True
    If (FF <> "s") And (FF <> "c") And (FF <> "e") And (FF <> "m") Then Func = False
End Function
 
Public Function Ciff(uu As String) As Boolean
    Ciff = True
    If (uu <> "0") And (uu <> "1") And (uu <> "2") And (uu <> "3") And (uu <> "7") _
                        And (uu <> "4") And (uu <> "5") And (uu <> "6") _
                        And (uu <> "8") And (uu <> "9") And (uu <> ".") Then Ciff = False
End Function