blob: 2294e009286a58a81e2b4460c721a2398bdfeebe [file] [log] [blame]
-- --
-- --
-- G N A T . B U B B L E _ S O R T --
-- --
-- S p e c --
-- --
-- Copyright (C) 1995-2002 Ada Core Technologies, Inc. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 2, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT 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 distributed with GNAT; see file COPYING. If not, write --
-- to the Free Software Foundation, 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. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
-- Sort Utility (Using Bubblesort Algorithm)
-- This package provides a bubblesort routine that works with access to
-- subprogram parameters, so that it can be used with different types with
-- shared sorting code.
-- See also GNAT.Bubble_Sort_G and GNAT.Bubble_Sort_A. These are older
-- versions of this routine. In some cases GNAT.Bubble_Sort_G may be a
-- little faster than GNAT.Bubble_Sort, at the expense of generic code
-- duplication and a less convenient interface. The generic version also
-- has the advantage of being Pure, while this unit can only be Preelaborate.
package GNAT.Bubble_Sort is
pragma Preelaborate (Bubble_Sort);
-- The data to be sorted is assumed to be indexed by integer values from
-- 1 to N, where N is the number of items to be sorted.
type Xchg_Procedure is access procedure (Op1, Op2 : Natural);
-- A pointer to a procedure that exchanges the two data items whose
-- index values are Op1 and Op2.
type Lt_Function is access function (Op1, Op2 : Natural) return Boolean;
-- A pointer to a function that compares two items and returns True if
-- the item with index value Op1 is less than the item with Index value
-- Op2, and False if the Op1 item is greater than or equal to the Op2
-- item.
procedure Sort (N : Natural; Xchg : Xchg_Procedure; Lt : Lt_Function);
-- This procedures sorts items in the range from 1 to N into ascending
-- order making calls to Lt to do required comparisons, and calls to
-- Xchg to exchange items. The sort is stable, that is the order of
-- equal items in the input is preserved.
end GNAT.Bubble_Sort;