Automatic conversion of wrapper in C#
I've build wrapper-class intended to prevent reference types of being null, as a pre-condition code contra开发者_开发知识库ct.
public sealed class NotNullable<T>
where T : class
{
private T t;
public static implicit operator NotNullable<T>(T otherT)
{
otherT.CheckNull("Non-Nullable type");
return new NotNullable<T> {t = otherT};
}
public static implicit operator T(NotNullable<T> other)
{
return other.t;
}
}
This works finely, but a cast is always needed like when dealing with Nullable:
public void Foo(NonNullable<Bar> bar)
{
Console.WriteLine((Bar)bar);
}
Would it be possible to have the parameter of type NonNullable behave as if it were of type T, without having to cast it? Like in Spec#:
public string Foo(Bar! bar)
You could avoid the casting by making the object itself accessible via a Value
property, but it's debatable whether that's any better than casting it:
Console.WriteLine(bar.Value);
There are even tricks you can use to tell tools like ReSharper that this value is not null, either via XML or in-code annotations:
[NotNull]
public T Value { get { return t; } }
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