Question

is it possible to easily and dynamically decorate an object?

for example, lets say I have a List<PointF>. this list is actually a plot of the sine function. I’d like to go through these points and add a flag to each PointF of whether it’s a peak or not.

but I don’t want to create a new extended SpecialPointF or whatever, that has a boolean property.

judge me all you want for being lazy, but laziness is how awesome ideas are born (also bad ideas)

Edit: I’ll accept boxing solutions as well as any interesting hack you can come up with. there’s nothing really stopping me from deriving. I just want to know if there’s a more fun way.

Answer 1

If there’s a way you can calculate that per point, you don’t need to add a flag to it, you can use an extension method without having to extend it.

Something like PointF.isPeak();

It works something like:

public static class Extensions
{
    public static bool isPeak (this PointF p)
    {
        do crazy math...

        return result;
    }
}

And voilà, you have your calculation in your PointF class.

By the way, the public static class has to be in the outermost scope, cant be nested.