Support for double equality symbol (==)

Author: ws-garcia

src/VBAexpressions.cls

@@ -119,7 +119,7 @@ Option Base 0
 '
 '///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 ' CONSTANTS:
-Private pi As Double
+Private PI As Double
 Private PID2 As Double
 Private e As Double
 Private Const op_plus As String = "+"
@@ -131,6 +131,7 @@ Private Const op_Factorial As String = "!"
 Private Const op_mod As String = "%"
 Private Const op_power As String = "^"
 Private Const op_equal As String = "="
+Private Const op_equal_ As String = "=="
 Private Const op_inequality As String = "<>"
 Private Const op_gt As String = ">"
 Private Const op_lt As String = "<"
@@ -217,12 +218,13 @@ Public Enum OperatorToken
     otPower = 6                  '^
     otMod = 7                    '%
     otEqual = 101                '=
-    otNotEqual = 102             '<>
-    otGreaterThan = 103          '>
-    otLessThan = 104             '<
-    otGreaterThanOrEqual = 105   '>=
-    otLessThanOrEqual = 106      '<=
-    otLike = 107                 '$
+    otEqual_ = 102               '==
+    otNotEqual = 103             '<>
+    otGreaterThan = 104          '>
+    otLessThan = 105             '<
+    otGreaterThanOrEqual = 106   '>=
+    otLessThanOrEqual = 107      '<=
+    otLike = 108                 '$
     otLogicalAND = 201           '&
     otLogicalOR = 202            '|
     otLogicalXOR = 203           '||
@@ -1705,7 +1707,7 @@ Private Sub BottomLevelEval(ByRef aToken As token)
     Else
         If aToken.OperationToken < 200 Then 'Comparison operators
             Select Case aToken.OperationToken
-                Case OperatorToken.otEqual
+                Case OperatorToken.otEqual, OperatorToken.otEqual_
                     aToken.EvalResult = (CastOPtype(aToken.Arg1.Operand, aToken.Arg1.NegationFlagOn) = _
                                         CastOPtype(aToken.Arg2.Operand, aToken.Arg2.NegationFlagOn))
                 Case OperatorToken.otNotEqual
@@ -4053,24 +4055,29 @@ Private Function GetLCOpInfo(ByRef expression As String) As TokenInfo
     Dim GreatterOrEqualSymbolPos As Long
     Dim LessOrEqualSymbolPos As Long
     Dim EqualSymbolPos As Long
+    Dim EqualSymbolPos_ As Long
     Dim LessThanSymbolPos As Long
     Dim GreatterThanSymbolPos As Long
     Dim LogANDSymbolPos As Long
     Dim LogORSymbolPos As Long
     Dim LogXORSymbolPos As Long
     Dim LikeSymbolPos As Long
     Dim testChar As String
+    Dim testChar2 As String
 
     '@--------------------------------------------------------------------
     ' Comparisons first
     Do 'Discard false positives
         EqualSymbolPos = GetOPeratorSymbolPos(expression, op_equal, EqualSymbolPos + 1)
         If EqualSymbolPos > 2 Then
             testChar = MidB$(expression, EqualSymbolPos - 2, 2)
+            testChar2 = MidB$(expression, EqualSymbolPos + 2, 2) 'Check ahead for "=="
         Else
             testChar = vbNullString
+            testChar2 = vbNullString
         End If
-    Loop While EqualSymbolPos > 0 And testChar Like "[<>]"
+    Loop While EqualSymbolPos > 0 And (testChar Like "[<>=]" Or testChar2 = op_equal)
+    EqualSymbolPos_ = GetOPeratorSymbolPos(expression, op_equal_)
     NotEqualSymbolPos = GetOPeratorSymbolPos(expression, op_inequality)
     Do
         GreatterThanSymbolPos = GetOPeratorSymbolPos(expression, op_gt, GreatterThanSymbolPos + 1)
@@ -4091,15 +4098,18 @@ Private Function GetLCOpInfo(ByRef expression As String) As TokenInfo
     GreatterOrEqualSymbolPos = GetOPeratorSymbolPos(expression, op_gtequal)
     LessOrEqualSymbolPos = GetOPeratorSymbolPos(expression, op_ltequal)
     LikeSymbolPos = InStrB(LessThanSymbolPos + 1, expression, op_like)
-    If NonZero(EqualSymbolPos, NotEqualSymbolPos, GreatterThanSymbolPos, _
+    If NonZero(EqualSymbolPos, EqualSymbolPos_, NotEqualSymbolPos, GreatterThanSymbolPos, _
                 LessThanSymbolPos, GreatterOrEqualSymbolPos, LessOrEqualSymbolPos, LikeSymbolPos) Then
-        GetLCOpInfo.Position = MinNonZero(EqualSymbolPos, NotEqualSymbolPos, GreatterThanSymbolPos, _
+        GetLCOpInfo.Position = MinNonZero(EqualSymbolPos, EqualSymbolPos_, NotEqualSymbolPos, GreatterThanSymbolPos, _
                                     LessThanSymbolPos, GreatterOrEqualSymbolPos, LessOrEqualSymbolPos, _
                                     LikeSymbolPos)                                                         'Priority to the first operator
         Select Case GetLCOpInfo.Position
             Case EqualSymbolPos
                 GetLCOpInfo.OperationToken = otEqual
                 GetLCOpInfo.OperatorLen = LenB(op_equal)
+            Case EqualSymbolPos_
+                GetLCOpInfo.OperationToken = otEqual_
+                GetLCOpInfo.OperatorLen = LenB(op_equal_)
             Case NotEqualSymbolPos
                 GetLCOpInfo.OperationToken = otNotEqual
                 GetLCOpInfo.OperatorLen = LenB(op_inequality)
@@ -4287,6 +4297,7 @@ Private Function GetOpSymbol(ByRef OPtoken As OperatorToken) As String
         Case OperatorToken.otMod: GetOpSymbol = op_mod
         Case OperatorToken.otPower: GetOpSymbol = op_power
         Case OperatorToken.otEqual: GetOpSymbol = op_equal
+        Case OperatorToken.otEqual_: GetOpSymbol = op_equal_
         Case OperatorToken.otNotEqual: GetOpSymbol = op_inequality
         Case OperatorToken.otGreaterThan: GetOpSymbol = op_gt
         Case OperatorToken.otLessThan: GetOpSymbol = op_lt
@@ -9097,6 +9108,4 @@ err_Handler:
     Zero = e_ValueError
     BuildErrMessage errEvalError, d_lCurly & fName & d_rCurly & " | Error#: " & err.Number & d_Space & _
                                     d_lParenthesis & err.Description & d_rParenthesis
-End Function
-
-
+End Function