<HTML><FONT FACE=arial,helvetica><FONT SIZE=4 FAMILY="SERIF" FACE="Times New Roman" LANG="0">>>> setX_Circle(Circle, X) = Circle^x := X.
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<BR>Thanks.
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<BR>I think I finally got somewhat of a handle on the "object oriented" style
<BR>that's alluded to in the documentation on Existential Types - which is what I
<BR>set out to explore. Don't know whether dumping big chunks of code (like I
<BR>did before) is frowned upon, so I'll just give the link to the toy code at
<BR>http://www.angelfire.com/tx4/cus/shapes/mercury.html for anyone that might be
<BR>interested in an OOP style polymorphism example.
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