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This is a type  which provides access to an object. Access value and an allocator need to be used in order to access.

access subtype indication
type identifier;


Acces type, allows you to change the data of which the value is previously unknown and that will emerge only during the simulation. To do that, an identifier (allocator) like pointers are used.

Subtype Indication: The type of the object which is marked with a value. (It may be any scalar, composite, or other type of access, except File type.)

Only variable objects can be used as access type.

The default value of an access is “null”.

Access type allows dynamic lists of objects which are created during the simulation. They are essentially records which consist of elements that has the type of access. These elements may be in different types from previously declared. To do that, an incomplete type is used; by announcing the variables first, then declaring them later.

Incomplete declarations has to be completed in the same declarative part with the same name later on. They are already used only here.



--declaration of the personal_info:

type personal_info is record
end personal_info;

-- declaration of access type Person_Access
 type Person_Access is access personal_info;

Person_Access type allows to access personal_info which is defined as record.






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