SCL allows the definition of types which can then be subsequently used to define variables . There are several types of type definitions.
Enumeration type definitions give specific values that the type allows.
type color is (red, blue, green);
Range definitions give a range of values that the type allows.
type Byte is range 0 to #16#FF#;
Range definitions can include an option definition of the units associated with the type
type voltage is range -9223372036854775807 to 9223372036854775807
units mV;
V = 1000 mV;
kV = 1000 V;
end units;
Here is an example of an array type
type bit_vector is array (integer range <>) of bit;