LOTUSSCRIPT LANGUAGE

Boolean Operators
An expression consisting of two operands and a Boolean operator evaluates to True if the expression is true, and False if it is false, unless one of the operands is NULL. In that case, the result may be NULL or True or False, depending on the operator and the operand. The possibilities are:
OperatorIf expr1 isAnd expr2 isThe expression evaluates to
AndTrue True True
True False False
False True False
False False False
OrTrue True True
True False True
False True True
False False False
XorTrue True False
True False True
False True True
False False False
EqvTrue True True
True False False
False True False
False False True
ImpTrue True True
True False False
False True True
False False True
When an operand in a numeric expression including a Boolean operator is NULL, the whole expression evaluates to NULL except under the following circumstances:
This example has the user enter two integers between 1 and 10. It tests to see if the first (num1%) is less than 6 and if the second (num2%) is greater than 5. Then it displays a message according to the truth value of the two tests.

Dim num1 As Integer
Dim num2 As Integer
num1% = InputBox("Enter an integer between 1 and 10:")
num2% = InputBox("Enter an integer between 1 and 10:")
Print "num1 = " & num1% & " num2 = " & num2%
If num1% <6 And num2% >5 Then
  Print "And:" & num1% & " is less than 6 and " & num2% & _
     " is greater than 5."
End If
If num1% <6 Or num2% >5 Then
  Print "Or:" & num1% & " is less than 6 or " & num2% & _  
     " is greater than 5, or both."
End If
If num1% <6 XOr num2% >5 Then
  Print "XOr: " & num1% & " is less than 6 or " & num2% & _
     " is greater than 5, but not both."
End If
If num1% <6 Eqv num2% >5 Then
  Print "Eqv:" & num1% & " is less than 6 and " & num2% & _
     " is greater than 5, or " & num1% & _
     " is greater than 5 and " & num2% & " is less than 6."
End If
If num1% <6 Imp num2% >5 Then
  Print "Imp:" & num1% & " is less than 6 and " & num2% & _
     " is greater than 5, or " & num1% & _
     " is greater than 5 and " & num2% & _
     " is less than 6, or " & num1% &  _
     " is greater than 5 and " & num2% & _
     " is greater than 5."
End If
' Sample Output:
' num1 = 6 num2 = 6
' Or: 6 is less than 6 or 6 is greater than 5, or both.
' XOr: 6 is less than 6 or 6 is greater than 5, but not both.
' Imp: 6 is less than 6 and 6 is greater than 5, or 6 is
' greater than 5 and 6 is less than 6, or 6
' is greater than 5 and 6 is greater than 5.

' num1 = 10 num2 = 1
' Eqv: 10 is less than 6 and 1 is greater than 5, or 10
' is greater than 5 and 1 is less than 6.
' Imp: 10 is less than 6 and 1 is greater than 5, or 10 is
' greater than 5 and 1 is less than 6, or
' 10 is greater than 5 and 1 is greater than 5.

' num1 = 5 num2 = 9
' And: 5 is less than 6 and 9 is greater than 5.
' Or: 5 is less than 6 or 9 is greater than 5, or both.
' Eqv: 5 is less than 6 and 9 is greater than 5, or 5
' is greater than 5 and 9 is less than 6.
' Imp: 5 is less than 6 and 9 is greater than 5, or 5 is
' greater than 5 and 9 is less than 6, or
' 5 is greater than 5 and 9 is greater than 5.

See Also