{
GPC demo program about schemata (Extended Pascal feature).
Schemata are the Pascal way to get dynamic arrays without dirty
tricks (like `GetMem' with computed sizes). Although GPC supports
these dirty tricks, too, their use is not recommended.

Copyright (C) 1999 Free Software Foundation, Inc.

Author: Frank Heckenbach <frank@pascal.gnu.de>

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation, version 2.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; see the file COPYING. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.

As a special exception, if you incorporate even large parts of the
code of this demo program into another program with substantially
different functionality, this does not cause the other program to
be covered by the GNU General Public License. This exception does
not however invalidate any other reasons why it might be covered
by the GNU General Public License.
}

program SchemaDemo;

type
  Natural = 1 .. MaxInt;

  { A schema type. `Count' is the discriminant which can influence the size
    of the type. Discriminants must be specified when declaring variables,
    function return types and when allocating a schema variable with `New',
    but parameters and pointer types can refer to undiscriminated schemata. }
  TIntegers (Size : Integer) = array [1 .. Size] of Integer;

  { A pointer to this schema type. }
  PIntegers = ^TIntegers;

{ A procedure taking a schema parameter }
procedure Test (const Foo : TIntegers);
var i : Integer;
begin
  Writeln ('The procedure was called with a schema of size ', Foo.Size, ' with the value:');
  Write ('(');
  for i := 1 to Foo.Size do
    begin
      Write (Foo [i]);
      if i < Foo.Size then Write (', ')
    end;
  Writeln (')');
  Writeln
end;

const
  Foo : TIntegers (3) = (2, 3, 17);

var
  a, i : Integer;

begin
  Test (Foo);

  repeat
    Write ('Enter the size for a schema array: ');
    Readln (a)
  until a >= 1;

  { A schema array declared in the statement part (GPC extension) }
  var t : TIntegers (a);

  Writeln ('Enter the contents of the schema array:');
  for i := 1 to a do Read (t [i]);
  Writeln;
  Test (t)
end.
