[% setvar title More functions from set theory to manipulate arrays %]
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<a name='TITLE'></a><h1>TITLE</h1>
<p>More functions from set theory to manipulate arrays</p>
<a name='VERSION'></a><h1>VERSION</h1>
<pre>  Maintainer: Gael Pegliasco &lt;<a href='mailto:gael.pegliasco@telecorporate.com'>gael.pegliasco@telecorporate.com</a>&gt;
  Date: 30 Aug 2000
  Mailing List: <a href='mailto:perl6-language@perl.org'>perl6-language@perl.org</a>
  Number: 179
  Version: 1
  Status: Developing</pre>
<a name='ABSTRACT'></a><h1>ABSTRACT</h1>
<p>When programming in perl we need really often to calculate
union, intersection, difference between arrays. It will be
cool if such functions could be part of the perl6 language.</p>
<a name='DESCRIPTION'></a><h1>DESCRIPTION</h1>
<p>Functions from Set theory are often needed when manipulating arrays,
I'd like to to find most of them in the new perl6 language.</p>
<p>The most usefull and needed are, for me,</p>
<p>- union
- intersection
- difference</p>
<p>after we could find some others like :</p>
<p>- &quot;unicity&quot; to eliminate duplicated elements</p>
<a name='IMPLEMENTATION'></a><h1>IMPLEMENTATION</h1>
<p>I'd like to use these functions in this way :</p>
<pre> @c = union (@a, @b); 
 # wich is different from @c = (@a, @b) because union do not duplicate
 same elements

 @c = intersection (@a, @b);
 @c = diff(@a, @b);
 </pre>
<a name='Checkpointing'></a><h2>Checkpointing</h2>
<p>Don't know what to put here.</p>
<a name='Event loop'></a><h2>Event loop</h2>
<a name='REFERENCES'></a><h1>REFERENCES</h1>
<p>Set Theory</p>
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