[API Proposal]: static NotImplementedException throw helper.

[MaxMahem]

Background and motivation

With the CallerMemberName attribute, an informative static throw helper could be generated for NotImplementedException similar to some throw helpers on other exception types.

API Proposal

public class NotImplementedException : SystemException
{
+   [DoesNotReturn]
+   public static void Throw([CallerMemberName] string? unimplementedMemberName = null)
}

API Usage

public class MyClass : IMyInterface
{
    public void SomeUnimplementedMethod() => NotImplementedException.Throw();
}

Alternative Designs

Alternatively/additionally, an overload that returns a TReturn could be used so that the method could be used fluently:

public TReturn Throw<TReturn>([CallerMemberName] string? unimplementedMemberName = null)

Risks

N/A.

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[huoyaoyuan]

This is not as useful as ArgumentException.Throw* helpers, because:

• Argument exception helpers are wrapping testing logic together with throwing, but NotImplementedExeption is meant to be thrown unconditionally.
• Other throw helpers can separate the actual throwing statement from hot path of a method, but throwing NotImplementedExeption is meant to be the only statement of a method.
• Method name can be easily retrieved in stack trace. It's not as useful as parameter name, which can be multiple in a method.

[julealgon]

I'm against this one on the basis that NotImplementedException should only be used at development time, like // TODO comments, and are supposed to be removed before code is finalized.

I would be ok with a static guard for NotSupportedException however.