Version française
Home     About     Download     Resources     Contact us    

This site is updated infrequently. For up-to-date information, please visit the new OCaml website at

Browse thread
Re: new library modules
[ Home ] [ Index: by date | by threads ]
[ Search: ]

[ Message by date: previous | next ] [ Message in thread: previous | next ] [ Thread: previous | next ]
Date: 1993-05-04 (09:14)
From: cousinea@d...
Subject: Re: new library modules

The sets that you  propose are not only totally ordered sets
but rather totally pre-ordered  and I think that it is indeed important
for  many applications.  It is very often the case that you have
to deal with a set of complex objects  a part which is used for
the pre-order relation.
In that case, you will probably suggest to use a "map" but  "maps"
do not allow for multiple bindings.

 I have myself written a library for balanced trees and used it for
 several applications. I have found that, when dealing with equivalent
 elements, it is sometimes useful
     -  to allow equivalent elements to occur simultaneously in the tree.
    -  to  allow the user to precise, when using function "add" ,  the treatment
       he/she wants to be performed on equivalent elements (keeping both,
       keeping the old one, replacing the old one by the new one)

I am conscious that this goes beyond "set" operations but you get
these possibilities almost  for free when you have balanced trees
based on a pre-order relation.
Why not let us have access directly to your balanced trees package?

Rather than using type "int" for comparison, it would be clearer
to use an explicit type  comparison= Smaller | Equiv | Greater.