How to include shared code

[Emanuel Berg <embe8573@student.uu.se>]

If I have two files:

protected_buffer.adb
bounded_buffer.adb

and those compile and run fine.

But, in both those, I have this piece of code:

function Random_Integer return integer is
   type Span is range 1..9;
   package Random_Integer is new Ada.Numerics.Discrete_Random(Span);
   Seed    : Random_Integer.Generator;
   Outcome : Span;
begin
   Random_Integer.Reset(seed);
   Outcome := Random_Integer.Random(seed);
   return INTEGER(Outcome);
end Random_Integer;

function Random_Period return Time_Span is
begin
   return Milliseconds(Random_Integer*100);
end Random_Period;

Now, how can I extract that piece of code from both files, and put
it into another file, say, random_period.adb, and then "include"
it into each of the above files (that operate in isolation)?

-- 
Emanuel Berg - programmer (hire me! CV below)
computer projects: http://user.it.uu.se/~embe8573
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