ColdFusion expressions consist of operands and operators. Operands are comprised of constants and variables. Operators, such as the multiplication symbol, are the verbs that act on the operands; functions are a form of operator.

The simplest expression consists of a single operand with no operators. Complex expressions have multiple operators and operands. The following are all ColdFusion expressions:

12
MyVariable
a++
(1 + 1)/2
"father" & "Mother"
Form.divisor/Form.dividend
Round(3.14159)

Operators act on the operands. Some operators, such as functions with a single argument, take a single operand. Many operators, including most arithmetic and logical operators, take two operands. The following is the general form of a two-operand expression:

Expression Operator Expression

Note that the operator is surrounded by expressions. Each expression can be a simple operand (variable or constant) or a subexpression consisting of more operators and expressions. Complex expressions are built up using subexpressions. For example, in the expression (1 + 1)/2, 1 + 1 is a subexpression consisting of an operator and two operands.