Initial data commit

Task/Polymorphism/Haskell/polymorphism-2.hs

@@ -0,0 +1,63 @@
+class Circle (x, y, r)
+  # make a new copy of this instance
+  method copy ()
+    return Circle (x, y, r)
+  end
+
+  # print a representation of this instance
+  method print ()
+    write ("Circle (" || x || ", " || y || ", " || r || ")")
+  end
+
+  # called during instance construction, to pass in field values
+  initially (x, y, r)
+    self.x := if /x then 0 else x # set to 0 if argument not present
+    self.y := if /y then 0 else y
+    self.r := if /r then 0 else r
+
+end
+
+class Point (x, y)
+  # make a new copy of this instance
+  method copy ()
+    return Point (x, y)
+  end
+
+  # print a representation of this instance
+  method print ()
+    write ("Point (" || x || ", " || y || ")")
+  end
+
+  # called during instance construction, to pass in field values
+  initially (x, y)
+    self.x := if /x then 0 else x # set to 0 if argument not present
+    self.y := if /y then 0 else y
+
+end
+
+procedure main ()
+  p1 := Point ()
+  p2 := Point (1)
+  p3 := Point (1,2)
+  p4 := p3.copy ()
+
+  write ("Points:")
+  p1.print ()
+  p2.print ()
+  p3.print ()
+  p4.print ()
+  # demonstrate field mutator/accessor
+  p3.x := 3
+  write ("p3 value of x is: " || p3.x)
+
+  c1 := Circle ()
+  c2 := Circle (1)
+  c3 := Circle (1,2)
+  c4 := Circle (1,2,3)
+
+  write ("Circles:")
+  c1.print ()
+  c2.print ()
+  c3.print ()
+  c4.print ()
+end