13.14 Constant Declaration
A constant holds a value that does not change. A constant declaration specifies the name, data type, and value of the constant and allocates storage for it. The declaration can also impose the NOT NULL constraint.
Topics
Syntax
constant_declaration ::=
Semantics
constant_declaration
constant
Name of the constant that you are declaring.
datatype
Data type for which a variable can be declared with an initial value.
NOT NULL
Imposes the NOT NULL constraint on the constant.
For information about this constraint, see "NOT NULL Constraint".
expression
Initial value for the constant. expression must have a data type that is compatible with datatype. When constant_declaration is elaborated, the value of expression is assigned to constant.
Examples
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Example 2-12, "Constant Declarations"
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Example 2-13, "Variable and Constant Declarations with Initial Values"
Related Topics
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