Newbie question: Implementing a callback mechanism with Ada 83

["benibilme@gmail.com" <benibilme@gmail.com>]

Hello,

I need to develop an Ada application which must conform to Ada83. It
will be part of legacy system. I am very much new in Ada. The
application I have to develop is very much event driven. As an old
time C programmer I wanted to implement an event handling module which
you can subscribe callback functions and trigger the events when
necessary and unfortunately I have realized that Ada 83 does not
support pointer to subprograms. I have read about generics with which
defining subprograms as parameters of subprograms seems possible. On
the other hand, I could not figure out how to do it.

I simply want to store function pointers to some data structure for
some certain events and call them with dynamic data when the event is
triggered.

How can I do it in Ada 83 without the support of pointers to
subprograms. It is clear how to do this Ada95 as there is a direct
support for pointer to subprograms.

Any help is much appreciated.