From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: *
X-Spam-Status: No, score=1.1 required=5.0 tests=BAYES_20,INVALID_DATE,
	MSGID_SHORT autolearn=no autolearn_force=no version=3.4.4
Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!uunet!husc6!rutgers!mcnc!rti!jb
From: jb@rti.UUCP (Jeff Bartlett)
Newsgroups: comp.lang.ada,comp.lang.c
Subject: Re: "C" vrs ADA
Message-ID: <1678@rti.UUCP>
Date: Thu, 27-Aug-87 13:44:37 EDT
Article-I.D.: rti.1678
Posted: Thu Aug 27 13:44:37 1987
Date-Received: Sat, 29-Aug-87 10:01:47 EDT
References: <1065@vu-vlsi.UUCP> <2231@cbmvax.UUCP> <36@sarin.UUCP> <1937@sfsup.UUCP>
Distribution: na
Organization: Research Triangle Institute, RTP, NC
Summary: Illustrate a generic merge sort package that handles both fixed and floating types.
Xref: mnetor comp.lang.ada:588 comp.lang.c:3967
List-Id: <comp.lang.ada>

In article <1937@sfsup.UUCP>, mpl@sfsup.UUCP (M.P.Lindner) writes:
> [ the following are excerpts - see the original articles for context ]
> 
> ...... I do take exception, however to the statements that
> Ada is an "object oriented" language.  Yes, it is, but it was implemented
> no better than that of C++.  Example:  Try to make a generic merge sort
> which can sort floats and integers.  Unless this has been fixed since I
> learned Ada, it can't be done!  The reason I was given is a generic type
> can only assume assignment and equality.  If we add constraints, we must
> specify either integral types or floating types.  Little inconsistancies
> make life hell for programmers, as well as conflicting with the stated intent
> of the methodology.
> 
> Mike Lindner
> attunix!mpl

What about ......

   generic
      type ITEM is private;
      with function GREATER(A,B : ITEM) return BOOLEAN is <>;
   package SORTING is

      type VECTOR is array(NATURAL range <>) of ITEM;

      procedure MERGE_SORT( A, B : VECTOR; RESULTS : out VECTOR );

   end SORTING;

This generic package can be instatiated for fixed, floating and record types.

Jeff Bartlett
Center for Digital Systems Research
Research Triangle Institute
jb@rti.rti.org