Source code

Option Explicit 
Private errorCount As Integer = 0 
Private sErr As String = "" 
Public Sub main(ByJava args() As String) 
Call operatorCheck() 
End Sub 
Private Sub operatorCheck 
Dim obj As Object = New Object 

t "a", "&", "b", "a" & "b", "ab", "string concatenation" 
t "", "&", "b", "" & "b", "b", "string concatenation" 
t "a", "&", "", "a" & "", "a", "string concatenation" 
t "Null", "&", "b", Null & "b", "b", "String concatenation" 
t "a", "&", "Null", "a" & Null, "a", "String concatenation" 
t "Nothing", "&", "b", Nothing & "b", "b", "String concatenation" 
t "a", "&", "Nothing", "a" & Nothing, "a", "String concatenation" 

t "1", "*", "1", 1*1, 1, "multiply" 

' allowed neither in VB6 nor in Jabaco 
' t "Null", "*", "1", Null*1, Null, "multiply" 
' t "1", "*", "Null", 1*Null, Null, "multiply" 
' t "Null", "*", "Null", Null * Null, Null, "multiply" 

' t "Nothing", "*", "1", Nothing*1, Nothing, "multiply" 
' VB6 grumbles about overflow here 
t "20000", "*", "4", 20000 * 4, 80000, "multiply" 
' VB6 grumbles about overflow here 
t "70000", "*", "70000", 70000 * 70000, 4900000000, "multiply" 
' VB6 grumbles about overflow here 
t "70000", "*", "70000", 70000.0 * 70000.0, 4900000000, "multiply" 
t "70000", "*", "70000", CLng(70000) * CLng(70000), CLng(4900000000), "multiply" 

t "1", "+", "1", 1 + 1, 2, "add" 
' allowed neither in VB6 nor in Jabaco 
' t "Null", "+", "1", Null + 1, Null, "add" 

t "1", "-", "1", 1 - 1, 0, "subtract" 
' allowed neither in VB6 nor in Jabaco 
' t "Null", "-", "1", Null - 1, Null, "subtract" 
t "20", "/", "80", 20 / 80, 0.25, "float divide" 
t "20", "", "80", 20 \ 80, 0, "integer divide" 
t "2", "^", "10", CLng(2 ^ 10), CLng(1024), "power" 
t "25", "^", "0.5", CLng(25 ^ 0.5), CLng(5), "power" 
t "2", "^", "-1", 2 ^ -1, 0.5, "power" 

t "a", "=", "b", "a" = "b", False, "equals" 
t "a", "=", "a", "a" = "a", True, "equals" 
t "a", "<>", "b", "a" <> "b", True, "unequals" 
t "a", "<>", "a", "a" <> "a", False, "equals" 

t "12", "and", "10", 12 And 10, 8, "bitwise and" 
t "false", "and", "true", False And True, False, "and" 
t "true", "and", "false", True And False, False, "and" 
t "false", "and", "false", False And False, False, "and" 
t "true", "and", "true", True And True, True, "and" 


' allowed in VB6 but not implemented in Jabaco 
' t "Obj", "is", "Obj", obj Is obj, True, "is comparison" 

' t "a", "like", "[b-z]", "a" Like "[b-z]", False, "like comparison" 

' t "12", "eqv", "10", 12 eqv 10, -7, "eqv equivalence" 
' t "12", "imp", "10", 12 imp 10, -5, "imp implication" 

t "10", "mod", "5", 10 Mod 5, 0, "mod modulo" 
t "10", "mod", "3", 10 Mod 3, 1, "mod modulo" 
t "12", "mod", "4.3", round(12 Mod 4.3, 2), round(0.00, 2), "mod modulo" 
t "12.6", "mod", "5", round(12.6 Mod 5, 2), round(3.00, 2), "mod modulo" 

t "12", "not", "", Not 12, -12 - 1, "bitwise not" 
t "10", "not", "", Not 10, -10 - 1, "bitwise not" 

t "12", "or", "10", 12 Or 10, 14, "bitwise or" 
t "false", "or", "true", False Or True, True, "or" 
t "true", "or", "false", True Or False, True, "or" 
t "false", "or", "false", False Or False, False, "or" 
t "true", "or", "true", True Or True, True, "or" 
t "12", "xor", "10", 12 XOr 10, 6, "bitwise xor" 
t "false", "xor", "true", False XOr True, True, "xor" 
t "true", "xor", "false", True XOr False, True, "xor" 
t "false", "xor", "false", False XOr False, False, "or" 
t "true", "xor", "true", True XOr True, False, "xor" 
If ErrorCount > 0 Then 
msgbox "Errors: " & ErrorCount & vbcrlf & "-------------" & sErr 
End If 
End Sub 
Private Sub t(lVal As String, op As String, rVal As String, res As String, resComp As String, remark As String) 
Dim s As String 

If res <> resComp Then 
s = lVal & " " & op & " " & rVal & " = " & res & " <> " & resComp & " " & remark 
sErr = sErr & vbCrLf & s 
errorCount = errorCount + 1 
End If 
End Sub