Using implicit conversion as a replacement for multiple inheritance in .NET.

Question

I have a situation where I would like objects of a certain type to be used as two different types. If one of the "base" types was an interface, that would not be a problem, but in my case it is preferable that both of them be concrete types.

I am considering adding copies of the methods and properties of one of the base types to a derived type and adding an implicit conversion from a derived type to this base type. Then users will be able to process the derived type as the base type using the duplicated methods directly, assigning it to a variable of the base type or passing it to a method that takes the base type.

It seems that this solution will satisfy my needs, but I did not miss anything? Is there a situation where this does not work, or where is it likely to add confusion instead of simplicity when using the API?

EDIT: More about my specific scenario:

This is a potential future redesign of how indicators are written in RightEdge , which is the development environment for an automated trading system. Price data are presented as a series of bars that are relevant for open, low, high and closed prices for a given period (1 minute, 1 day, etc.). Indicators perform calculations on a series of data. An example of a simple indicator is a moving average indicator, which gives a moving average of the last n values ​​of its input, where n is set by the user. A moving average can be applied to close the panel, or it can be applied to the output of another indicator to smooth it.

Each time a new bar appears, indicators calculate a new value for their output for this line.

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Answer 2

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class Person { }

abstract class Student : Person
{
    public abstract decimal Wage { get; }
}

abstract class Musician : Person
{
    public abstract decimal Wage { get; }
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class StudentMusician : Person
{
    public decimal MusicianWage { get { return 10; } }

    public decimal StudentWage { get { return 8; } }

    public Musician AsMusician() { return new MusicianFacade(this); }

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}

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class Bar
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    double Open { get; }
    double Low { get; }
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    double Close { get; }
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class Series : IObservable<Bar>
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static class IndicatorExtensions
{
    public static IObservable<double> MovingAverage(
        this IObservable<Bar> source,
        int count)
    {
        // ...
    }
}

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Series series = GetSeries();

series.MovingAverage(20).Subscribe(average =>
{
    txtCurrentAverage.Text = average.ToString();
});

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Answer 6

It might be a dumb idea, but: if your design requires multiple inheritance, then why don't you just use the language with MI? There are several .NET languages ​​that support multiple inheritance. From head to head: Eiffel, Python, Yok. Most likely.