Allow hide required property with another required property CS9031

[UniqeId6542]

If a 'new' property hides and sets the base class's property, it should not make a compiler error. (Or, add an attribute to help support it)

public class A
{
    public required object Value { get; init; }
}

public class B : A
{
    public new required string Value // CS9031 - should compile as base.Value is set in init
    {
        get => (string)base.Value;
        init => base.Value = value;
    }
}

[RikkiGibson]

This is a language design suggestion, so moving to csharplang.

[TahirAhmadov]

The problem here is that we would need some syntax to "advertise" that B.Value unconditionally sets A.Value. I don't think C# typically interprets the code in methods to infer the signature (including property setters). Also, what about properties which have a different name, and not new (hiding) ones?

[UniqeId6542]

we would need some syntax to "advertise"

Yes. Constructors can use the SetsRequiredMembers attribute. This issue would (probably) need something where you could pass in the property name. The implementation gets more difficult in needing to have a way to differentiate B.Value from A.Value.