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Comment by nightski | Hacker News Reader

I'd be curious which features you think C# messed up on. I have been using C# professionally since 2000 in it's first beta and can't think of a newer feature that would meet this criteria?

That said you are correct about records. Although it is getting them also.

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The one that annoys me the most in C# on a day-to-day basis is Nullable<T>. Java took their time with Optional<T> but once it was released it was great. Can be used in lambdas, all libraries are modified and aware of it etc. C# Nullable<T> is near useless because it only works on value types. I.e., you know, the types that are least likely to generate NullReferenceException for you.

In both C# and Java, reference types are nullable. Nullable<T> exists in C# to provide for nullable value types. It's not comparable to Optional<T> as that's an entirely different feature.

They aren’t “entirely different feature”. Why do you think C#8 introduced Nullable reference types that work exactly like Java Optional ? https://docs.microsoft.com/en-us/dotnet/csharp/nullable-refe...

> C# Nullable<T> is near useless because it only works on value types. I.e., you know, the types that are least likely to generate NullReferenceException for you.

You are completely missing the point of Nullable. It was introduced because databases allowed int, float, etc ( value types ) to be null. It was never meant to be an Option type. Reference types are already "nullable" so the database returning null for strings wasn't a problem. But databases returning nulls for int was a problem. It led to performance issues ( boxing and/or adding additional code to marshal data from one source to another ). If you find Nullable to be annoying then you either don't code in C# much and you especially don't deal with data/databases.

For what it was intended for, Nullable did it's job. And if Nullable is your only complaint, given the extraordinary changes that C# has gone through, I think it speaks well for C#.

> You are completely missing the point of Nullable

Am I? Apparently so is everyone else because Microsoft has re-worked Nullable<T> in C# 8 to be almost exactly like Java Optional! Silly me right?

Nullable/Non-nullable reference types in C# 8.0 having nothing to do with Nullable<T> and aren't even implemented using it.

C# 8.0 implementation of something like Optional<T> for reference types uses static flow analysis to ensure correct use of potentially null values. That's vastly superior in every way to Optional<T>.

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