Not sure if the offer was only open to OP but I'll bite. How about Java?
Integer.valueOf(5) == Integer.valueOf(5)
true
Integer.valueOf(200) == Integer.valueOf(200)
falseYou don't compare non-primitives (which boxed integers are) with == in Java, you use the equals method.
And in fact when I googled to find the exact range where it switches from cached integers to truly creating new objects, the top link was at best highly misleading. https://www.tutorialspoint.com/check-two-numbers-for-equalit...
If you want a instance, I recommend new :)
Integer val1 = 5;
Integer val2 = 5;
Integer val3 = 200;
Integer val4 = 200;
The general reply is 'you're holding it wrong', but that doesn't make it any less absurd. That's what the PHPers say about "123" < "456A" < "78" < "123".
2. Java does not allow to create wrappers without incurring a significant memory overhead. A wrapper will consume at least 32 bytes of memory on 64-bit systems just for itself, when in Rust this can be 0.
3. Even if you define a wrapper, it would be way less ergonomic than in Rust - there is nothing like AsRef / Deref / From / Into etc machinery in Java.
JNI is a nightmare.
Strings are UTF-16.
Dealing with installing the JVM, whatever the hell "classpath" is, tweaking GC parameters etc. is a big downside.
Despite that it's definitely one of the saner languages out there.