1------------------------------------------------------------------------------ 2-- -- 3-- GNAT RUN-TIME COMPONENTS -- 4-- -- 5-- G N A T . B U B B L E _ S O R T -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 1995-2010, AdaCore -- 10-- -- 11-- GNAT is free software; you can redistribute it and/or modify it under -- 12-- terms of the GNU General Public License as published by the Free Soft- -- 13-- ware Foundation; either version 3, or (at your option) any later ver- -- 14-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- 15-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- 16-- or FITNESS FOR A PARTICULAR PURPOSE. -- 17-- -- 18-- As a special exception under Section 7 of GPL version 3, you are granted -- 19-- additional permissions described in the GCC Runtime Library Exception, -- 20-- version 3.1, as published by the Free Software Foundation. -- 21-- -- 22-- You should have received a copy of the GNU General Public License and -- 23-- a copy of the GCC Runtime Library Exception along with this program; -- 24-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- 25-- <http://www.gnu.org/licenses/>. -- 26-- -- 27-- GNAT was originally developed by the GNAT team at New York University. -- 28-- Extensive contributions were provided by Ada Core Technologies Inc. -- 29-- -- 30------------------------------------------------------------------------------ 31 32-- Sort Utility (Using Bubblesort Algorithm) 33 34-- This package provides a bubblesort routine that works with access to 35-- subprogram parameters, so that it can be used with different types with 36-- shared sorting code. 37 38-- See also GNAT.Bubble_Sort_G and GNAT.Bubble_Sort_A. These are older 39-- versions of this routine. In some cases GNAT.Bubble_Sort_G may be a 40-- little faster than GNAT.Bubble_Sort, at the expense of generic code 41-- duplication and a less convenient interface. The generic version also 42-- has the advantage of being Pure, while this unit can only be Preelaborate. 43 44package GNAT.Bubble_Sort is 45 pragma Pure; 46 47 -- The data to be sorted is assumed to be indexed by integer values from 48 -- 1 to N, where N is the number of items to be sorted. 49 50 type Xchg_Procedure is access procedure (Op1, Op2 : Natural); 51 -- A pointer to a procedure that exchanges the two data items whose 52 -- index values are Op1 and Op2. 53 54 type Lt_Function is access function (Op1, Op2 : Natural) return Boolean; 55 -- A pointer to a function that compares two items and returns True if 56 -- the item with index value Op1 is less than the item with Index value 57 -- Op2, and False if the Op1 item is greater than or equal to the Op2 58 -- item. 59 60 procedure Sort (N : Natural; Xchg : Xchg_Procedure; Lt : Lt_Function); 61 -- This procedures sorts items in the range from 1 to N into ascending 62 -- order making calls to Lt to do required comparisons, and calls to 63 -- Xchg to exchange items. The sort is stable, that is the order of 64 -- equal items in the input is preserved. 65 66end GNAT.Bubble_Sort; 67