System.Diagnostics.CodeAnalysis.NotNullIfNotNullAttribute
Specifies that the output will be non-null if the named parameter is non-null.
namespace System.Diagnostics.CodeAnalysis
{
internal sealed class NotNullIfNotNullAttribute : Attribute
{
public string ParameterName { get; }
public NotNullIfNotNullAttribute(string parameterName);
}
}