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From: Jon.Guthrie@p25.f506.n106.z1.fidonet.org (Jon Guthrie)
Newsgroups: comp.lang.modula2
Subject: Re: Procedure Variables and Records and Sorting
Message-ID: <3139.27EBB45D@puddle.fidonet.org>
Date: 22 Mar 91 02:15:25 GMT
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 On a message of 19-Mar-91, George Emery (1:105/6.0) Said:

 > Making use of procedure variables to set the sort method is old hat to
 > most folks.  What I'm trying to figure (can it even be done?) is a way
 > to allow a procedure to sort different types of records.

In C, this sort of thing is a piece of cake because of the looser
typing.  Unfortunately, there's no way to define the type of an array
argument at runtime.  So, unless you're willing to put up with a
hideously ugly kludge, there's no way to write a general array sort in
Modula-2.  However...

It IS possible to write a generic linked-list sorting routine in M-2.
I, and others, have done so in C and I'm willing to convert the C code
that I have into M-2.

Of course, none of this does you the slightest bit of good if you
don't want to sort linked lists.  (You don't say what you want to
sort, but most people prefer to deal with arrays.)



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