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Task/Polymorphism/Nim/polymorphism.nim

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+type
+  Point = object
+    x, y: float
+
+  Circle = object
+    center: Point
+    radius: float
+
+# Constructors
+proc createPoint(x, y = 0.0): Point =
+  result.x = x
+  result.y = y
+
+proc createCircle(x, y = 0.0, radius = 1.0): Circle =
+  result.center.x = x
+  result.center.y = y
+  result.radius = radius
+
+var p1 = createPoint()
+echo "p1: ", p1 # We use the default $ operator for printing
+var p2 = createPoint(3, 4.2)
+var p3 = createPoint(x = 2)
+var p4 = createPoint(y = 2.5)
+
+p2 = p4
+p3 = createPoint()
+
+var c1 = createCircle()
+echo "c1: ", c1
+var c2 = createCircle(2, 0.5, 4.2)
+var c3 = createCircle(x = 2.1, y = 2)
+var c4 = createCircle(radius = 10)
+
+c1.center.x = 12
+c1.radius = 5.2