Syntax

numExpr1 + numExpr2

Elements

numExpr1, numExpr2

Any numeric expressions. An EMPTY operand is considered a 0.

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.

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.

Language cross-reference

@Sum function in formula language

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"

See Also

Arithmetic Operators
Operator order of precedence
Table of numeric operators
Overview of expressions and operators

Glossary