HP 3000 Manuals

HP Pascal/iX Reference Manual

Recursion 

A recursive procedure or function is a procedure or function that calls
itself.  It is also legal for procedure A to call procedure B that in
turn calls procedure A. This is indirect recursion and is often an
instance when the FORWARD directive is useful.  Note that when a routine
is called recursively, new local variables are created for each
invocation of the routine.

Example 

     FUNCTION factorial (n: integer): integer;
     { Calculates factorial recursively }

     BEGIN
        IF n = 0 THEN
           factorial := 1
        ELSE
           factorial := n * factorial(n-1);
     END;

MPE/iX 5.0 Documentation