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Re:Records Come to Java by anthonybsd on Thursday January 16, 2020 @06:13PM (#22070105)
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.
Re:Records Come to Java by wvenable on Thursday January 16, 2020 @06:32PM (#22070254)
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.
Re:Records Come to Java by anthonybsd on Thursday January 16, 2020 @07:03PM (#22070473)
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...
Re:Records Come to Java by elfexec on Thursday January 16, 2020 @07:06PM (#22070487)
> 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#.

Re:Records Come to Java by anthonybsd on Thursday January 16, 2020 @07:19PM (#22070577)
> 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?

Re:Records Come to Java by wvenable on Thursday January 16, 2020 @08:02PM (#22070837)
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>.

[dead]
Re:Records Come to Java by wvenable on Friday January 17, 2020 @12:29AM (#22072152)
Yes, because it's checked by the compiler using normal constructs.

    someNullableInstance.DoSomething();  // compiler error
    if (someNullableInstance != null) 
        someNullableInstance.DoSomething();  // not an error
Option<T> is fine but it's a lot of syntax to use correctly.