Built-in type providing run-time type information

type object
as fb_BaseVT ptr vtable_ptr
declare constructor()
end type

type typename extends object
end type
dim variable as object

Object is a built-in type which provides Run-Time Type Information (RTTI) for all types derived from it using Extends, allowing them to be used with Operator Is, and to support Virtual and Abstract methods.
Extending the built-in Object type allows to add an extra hidden vtable pointer field at the top of the Type. The vtable is used to dispatch Virtual and Abstract methods and to access information for run-time type identification used by Operator Is.

See the Operator Is page, the Virtual and Abstract pages.

Dialect Differences:
Differences from QB:
See also:
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