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About Expressions

An expression is a collection of two or more terms that perform a mathematical or logical operation. The terms are typically variables or functions that you use with an operator to evaluate to a string or numeric result. You can use an expression to perform a calculation, manipulate a variable, or concatenate a string.

Siebel VB evaluates an expression according to precedence order. You can use parentheses to override the default precedence order. The following operators are listed in order of highest precedence to lowest precedence:

1. Numeric Operators
2. String Operators
3. Comparison Operators
4. Logical Operators

Numeric Operators

Table 6 describes numeric operators.

String Operators

Table 7 describes string operators.

Comparison Operators

Table 8 describes comparison operators. For a number, Siebel VB increases the operands to the least common type:

• Integer is preferable to Long.
• Long is preferable to Single.
• Single is preferable to Double.

For a string, the comparison is case-sensitive and is according to the collating sequence that the language specifies in the Microsoft Windows Control Panel. The result is 0 for FALSE and negative 1 for TRUE.

Logical Operators

Table 9 describes logical operators. Siebel VB performs a bitwise operation for each operator.