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fn self => fn x => self := (!self # {X = x});
val pointClass =
{
getX = fn self => #X (!self),
setX = fn self => fn x => self := (!self # {X = x}),
getY = fn self => #Y (!self),
setY = fn self => fn x => self := (!self # {Y = x}),
getColor = fn self => #Color (!self),
setColor = fn self => fn x => self := (!self # {Color = x})
};
local
val state = ref { X = 0.0, Y = 0.0 }
in
val myPoint = fn method => method pointClass state
end;
local
val state = ref { X = 0.0, Y = 0.0, Color = "Red" }
in
val myColorPoint = fn method => method pointClass state
end;
myPoint # setX 1.0;
myPoint # getX;
myColorPoint # getX;
myColorPoint # getColor;
myPoint # getColor;
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