File : asgc-ordered-sortable.adb
-- The Ada Structured Library - A set of container classes and general
-- tools for use with Ada95.
-- Copyright (C) 1998-1999 Corey Minyard (minyard@acm.org)
--
-- This library 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; either version 2 of the License, or (at your
-- option) any later version.
--
-- This library 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 library; if not, write to the Free Software Foundation, Inc.,
-- 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
--
-- As a special exception, if other files instantiate generics from this
-- unit, or you link this unit with other files to produce an executable,
-- this unit does not by itself cause the resulting executable to be
-- covered by the GNU General Public License. This exception does not
-- however invalidate any other reasons why the executable file might be
-- covered by the GNU Public License.
--
package body Asgc.Ordered.Sortable is
procedure Binary_Search (O : access Object;
Val : in Contained_Type;
Found : out Boolean;
Iter : in out Iterator'Class) is
Last_Pos : Natural := Member_Count(Object'Class(O.all));
First_Pos : Natural := 0;
Curr : Natural;
begin
Found := False;
Curr := Last_Pos;
while (First_Pos < Curr) loop
Set_Loc(Iter, Curr);
if (Iter = Val) then
Found := True;
exit;
elsif (Iter > Val) then
Last_Pos := Curr;
Curr := (Curr + First_Pos) / 2;
else
First_Pos := Curr;
Curr := (Curr + Last_Pos) / 2;
end if;
end loop;
end Binary_Search;
end Asgc.Ordered.Sortable;