c#-8.0

I was playing around with C# 8.0 preview and can't get IAsyncEnumerable to work. I tried the following public static async IAsyncEnumerable<int> Get() { for(int i=0; i<10; i++) { await Task.Delay(100); yield return i; } } I ended up using a Nuget package named AsyncEnumerator , but I'm getting the following error: Error CS1061 ' IAsyncEnumerable<int> ' does not contain a definition for ' GetAwaiter ' and no accessible extension method ' GetAwaiter ' accepting a first argument of type ' IAsyncEnumerable<int> ' could be found (are you missing a using directive or an assembly reference?) Error

I'm trying to detect whether a type can be nullable or not at runtime to convert that type to the corresponding GraphQL type so that, for example: With nullable reference types enabled : string is converted to String! string? is converted to String With nullable reference types disabled : string is converted to String NonNull<string> is converted to String! ( NonNull is a custom library type) I'm having trouble adapting the code that detected the nullability of a type: bool isNullable = !typeInfo.IsValueType; How can I change it so that it works with nullable reference types both enabled and

I know that an abstract class is a special kind of class that cannot be instantiated. An abstract class is only to be sub-classed (inherited from). In other words, it only allows other classes to inherit from it but cannot be instantiated. The advantage is that it enforces certain hierarchies for all the subclasses. In simple words, it is a kind of contract that forces all the subclasses to carry on the same hierarchies or standards. Also I know that An interface is not a class. It is an entity that is defined by the word Interface. An interface has no implementation; it only has the signature

I've recently seen the following code: public class Person { //line 1 public string FirstName { get; } //line 2 public string LastName { get; } = null!; //assign null is possible public string? MiddleName {get; } = null; public Person(string firstName, string lastName, string middleName) { FirstName = firstName; LastName = lastName; MiddleName = middleName; } public Person(string firstName, string lastName) { FirstName = firstName; LastName = lastName; MiddleName = null; } } Basically I try to dig into new c# 8 features. One of them is NullableReferenceTypes . Actually there're a lot of