Yurttas/PL/IL/Ada-95/ProgUnits/G/ex 04.adb

 1--
 2-- Copyright (C) 1998
 3-- All Rights Reserved. Salih Yurttas, ZCubes, BitsOfCode Software Systems, Inc..
 4--
 5-- Permission to use, copy, modify, and distribute this
 6-- software and its documentation for EDUCATIONAL purposes
 7-- and without fee is hereby granted provided that this
 8-- copyright notice appears in all copies.
 9--
10--
11 
12-- date   : January 1, 1998.
13-- author : Salih Yurttas.
14
15-- purpose : to demonstrate a procedure structure with nested
16--           procedures in Ada-95 programming structuring and
17--           composition.
18
19-- ex_04.adb
20
21
22with Text_IO; use Text_IO;
23
24procedure EX_04 is 
25
26  package Int_IO is new Integer_IO(Integer); use Int_IO;
27
28  A : Integer := 1;
29  B : Integer := 5;
30
31  X : Integer := 2;
32  Y : Integer := 8;
33
34  procedure P(H  : in String;
35              A,
36              B  : in Integer) is 
37  begin
38    New_Line;
39    Put_Line(H);
40    Put(A,1);
41    New_Line;
42    Put(B,1);
43    New_Line;
44  end P;
45
46  procedure E(A,
47              B  : in out Integer) is
48    T : Integer;
49  begin
50    T := A;
51    A := B;
52    B := T;
53  end E;
54
55begin
56
57  P("A-B before / ", A, B);
58
59  E(A, B);
60
61  P("A-B after / ", A, B);
62
63  E(A, B);
64
65  New_Line;
66
67  P("X-Y before / ", X, Y);
68
69  E(X, Y);
70
71  P("X-Y after / ", X, Y);
72
73  E(X, Y);
74
75end EX_04;