Simon,<br><br>Regarding Justin Bailey&#39;s idea of a calculator -- here&#39;s a twist. There is some sample Haskell code of Conway&#39;s account of numbers as games floating around the internet (<a href="http://www.dcs.ed.ac.uk/home/pgh/conway.html">
http://www.dcs.ed.ac.uk/home/pgh/conway.html</a>, <a href="http://www.dcs.ed.ac.uk/home/pgh/Conway.lhs">http://www.dcs.ed.ac.uk/home/pgh/Conway.lhs</a>). i can&#39;t vouch for the code as i have not read it in anger. However, i&#39;ve always thought it would be fun to do the standard calculator example, but with Conway games on the back end for doing the arithemetic.
<br><br>Some of the attractions:<br><ul><li>you could have another set of buttons for displaying the games respresentation of the numbers</li><li>you could really emphasize the polymorphism of the basic operations</li><li>
you could emphasize the use of laziness for calculations involving infinitary entities</li><li>you could explain Conway games (which are an intellectual treat for those who never seen them and just get better and better the more you return to them)
</li></ul>Best wishes,<br><br>--greg<br><br>-- <br>L.G. Meredith<br>Managing Partner<br>Biosimilarity LLC<br>505 N 72nd St<br>Seattle, WA 98103<br><br>+1 206.650.3740<br><br><a href="http://biosimilarity.blogspot.com">http://biosimilarity.blogspot.com
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