Addition operator (LotusScript® Language)
Finds the sum of two numbers.
Syntax
numExpr1 + numExpr2
Elements
numExpr1, numExpr2
Any numeric expressions. An EMPTY operand is considered a 0.
Return value
When adding expressions of numeric data types, the result is a value whose data type in most cases is the same as that of the operand whose data type is latest in this ordering: Integer, Long, Single, Double, Currency. For example, if one operand is a Double and the other is an Integer, then the data type of the result is Double.
The exceptions are:
- When the resulting data type is a Variant of Integer that overflows its legal range, the result is converted to a Variant of Long.
- If numExpr1 and numExpr2 are both EMPTY, the result has Integer.
- When the resulting data type is a Variant of Long, Single, or Date/Time that overflows its legal range, the result is converted to a Variant of Double.
Usage
LotusScript® interprets the + operator as either addition or string concatenation, depending on the data types of expr1 and expr2. The following table lists these interpretations. The numeric data types are Integer, Long, Single, Double, Currency, and (in a Variant variable only) Date/Time.
One expression |
Other expression |
Operation |
---|---|---|
Numeric |
Numeric |
Addition |
Numeric |
String |
(Type mismatch error occurs) |
Numeric |
Variant (other than NULL) |
Addition |
String |
Variant (other than NULL) |
String concatenation |
String |
String |
String concatenation |
Any type |
Variant that contains EMPTY |
Returns first expression |
Any type |
NULL |
Returns NULL |
Variant of numeric data type |
Variant of numeric data type |
Addition |
Variant of numeric data type |
Variant of String data type |
Addition, if string can be converted to a numeric data type; otherwise a type mismatch error occurs |
Variant of String data type |
Variant of String data type |
String concatenation |
To avoid confusion, use the & operator, not the + operator, for string concatenation.
Example
Dim a As Variant
Dim b As Integer
a = "8"
b% = 7
' Use operator for addition.
Print 8 + 7 ' Prints 15
Print a + 7 ' Prints 15
Print 8 + b% ' Prints 15
Print a + b% ' Prints 15
' Use operator for string concatenation.
Print "Hello " + "there" ' Prints "Hello there"
Print a + "7" ' Prints "87"