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...this is what Java gets instead of smth actually useful like structs/records/dataclasses with pass-by-value semantics?

by nnq 6y ago

pulse7 6y ago
...pass-by-value is also coming and it will be called "inline objects". See: http://cr.openjdk.java.net/~briangoetz/valhalla/sov/01-background.html http://cr.openjdk.java.net/~briangoetz/valhalla/sov/01-backg...
- nnq 6y ago
  interesting... so `inline class` would behave like `struct` in C#? Took them a while (and I'd imagine it's one reason why game engines like Unity, Godot etc. chose C#), but cool!
  - apta 6y ago
    Not quite like structs. From my understanding, Java's inline types are immutable.
deleted 6y ago
[deleted]
enitihas 6y ago
Java is getting other things, text blocks don't have to be excluded due to those 1. Records are already there AFAIK 2. Structs (Value types) will come as part of Valhalla 3. Records are the impl of dataclasses 4. Pass by value is already there for primitive types. Valhalla might bring that to structs also. Java is also getting a lot of good stuff like coroutines(Loom), and Panama(seamless FFI).
- nnq 6y ago
  Thanks for making me curious... Cool new developments, didn't touch Java in a while! > Records are the impl of dataclasses This is ofc backwards/reverse of any sane logic that would start with value types and after invent references (eg. in this case probably would've mean introducing a new composed-primitive type)... but then again, it's Java, at least they got the strings being immutable part right from the start.
  - chhum 6y ago
    Detailed piece on Records here: https://www.infoq.com/articles/java-14-feature-spotlight/ https://www.infoq.com/articles/java-14-feature-spotlight/
- hyperpape 6y ago
  Records are still a preview feature in Java 14 (Apr 2020). Java 15 (Fall 2020) contains a second preview. They're usable, but you have to pass a flag to the compiler to enable them, and you run some small risk that the syntax will change (it's pretty simple, so I'd guess that won't happen). I'm guessing that they'll land in Spring or Fall 2021, but that's just an outsider's guess. The really important cutoff is Spring 2022, when Java 18 is intended to be an LTS version.
  - J-Kuhn 6y ago
    You have to pass `--enable-preview` to BOTH compiler and runtime. If you think about it - the feature may change significantly or be even removed - it makes sense to only support a preview features in one java version. Providing backward compatibility for preview features is simply not intended.
- _ink_ 6y ago
  Loom and Panama look really cool, but when will they make it into the JDK?
  - enitihas 6y ago
    One of the loom developers is in this thread. Let's hope he answers.
    - pron 6y ago
      Hi. When it's ready, and it will be delivered piecemeal. It will also probably be in Preview, first, so you'll know before it lands in GA.

...this is what Java gets instead of smth actually useful like structs/records/dataclasses with pass-by-value semantics?

by nnq 6y ago

...this is what Java gets instead of smth actually useful like structs/records/dataclasses with pass-by-value semantics?

pulse7 6y ago

...pass-by-value is also coming and it will be called "inline objects". See: http://cr.openjdk.java.net/~briangoetz/valhalla/sov/01-background.html http://cr.openjdk.java.net/~briangoetz/valhalla/sov/01-backg...

nnq 6y ago
interesting... so `inline class` would behave like `struct` in C#? Took them a while (and I'd imagine it's one reason why game engines like Unity, Godot etc. chose C#), but cool!
- apta 6y ago
  Not quite like structs. From my understanding, Java's inline types are immutable.

deleted 6y ago

[deleted]

enitihas 6y ago

Java is getting other things, text blocks don't have to be excluded due to those 1. Records are already there AFAIK 2. Structs (Value types) will come as part of Valhalla 3. Records are the impl of dataclasses 4. Pass by value is already there for primitive types. Valhalla might bring that to structs also. Java is also getting a lot of good stuff like coroutines(Loom), and Panama(seamless FFI).

nnq 6y ago
Thanks for making me curious... Cool new developments, didn't touch Java in a while! > Records are the impl of dataclasses This is ofc backwards/reverse of any sane logic that would start with value types and after invent references (eg. in this case probably would've mean introducing a new composed-primitive type)... but then again, it's Java, at least they got the strings being immutable part right from the start.
- chhum 6y ago
  Detailed piece on Records here: https://www.infoq.com/articles/java-14-feature-spotlight/ https://www.infoq.com/articles/java-14-feature-spotlight/
hyperpape 6y ago
Records are still a preview feature in Java 14 (Apr 2020). Java 15 (Fall 2020) contains a second preview. They're usable, but you have to pass a flag to the compiler to enable them, and you run some small risk that the syntax will change (it's pretty simple, so I'd guess that won't happen). I'm guessing that they'll land in Spring or Fall 2021, but that's just an outsider's guess. The really important cutoff is Spring 2022, when Java 18 is intended to be an LTS version.
- J-Kuhn 6y ago
  You have to pass `--enable-preview` to BOTH compiler and runtime. If you think about it - the feature may change significantly or be even removed - it makes sense to only support a preview features in one java version. Providing backward compatibility for preview features is simply not intended.
_ink_ 6y ago
Loom and Panama look really cool, but when will they make it into the JDK?
- enitihas 6y ago
  One of the loom developers is in this thread. Let's hope he answers.
  - pron 6y ago
    Hi. When it's ready, and it will be delivered piecemeal. It will also probably be in Preview, first, so you'll know before it lands in GA.