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Type

All signals, variables, constants (i.e. objects) and expressions have a type.
The type defines the set of values that the object or expression can have. A type also determines the set of operations (operators, functions and procedures) which can be performed on that object or expression.

There are eight kinds of type:
  • Access
  • Array
  • Enumeration
  • File
  • Floating
  • Integer
  • Physical
  • Record

Rules

A value of one type cannot be assigned to an object of a different type.
The initial value of an object is the leftmost value of the type, i.e. the value on the left of the base enumeration, floating, integer or physical type.

Tips

Types are often best defined in packages, which contain common, shared definitions.

See Also

Subtype, Data Type, Package