I recently discovered Scala Native, a version of Scala that compiles to a native executable rather than running on the JVM like the original Scala. (via Modern Systems Programming with Scala Native)
Scala is an attractive language. Scala is to Java as C++ is to C. Meaning it's much more complex. (Scala promotes its simple syntax, but that doesn't mean it's a simple language.)
In some ways I like Kotlin better than Scala. It seems to give a lot of the advantages of Scala, without Scala's complexity. And there are non-JVM versions of Kotlin. But the problem is that Kotlin relies on the Java libraries, which is a portability problem for the non-JVM versions. Whereas, one of the strengths of Scala is its libraries (e.g. collections).
Libraries bring up an interesting issue. To write good libraries seems to require more features and complexity than application code. A lot of the complexity of C++ is to enable writing good libraries, and I suspect the same is true of Scala. The other alternative is the Go approach. Go has a built in "map" collection. You can't write map in the Go language. If you want a slightly different style of map, what you can write in Go is nothing like the built in one. This is at the heart of the Go generics struggle. On one hand, you want to be able to write your own map in Go. On the other hand, you want to keep Go's simplicity and not end up with another C++.
Another factor is that people seem to like complexity, regardless of whether it's counter-productive, myself included, sadly. Languages like C++ are fascinating. There's always something more you can learn. Whereas simpler languages like Go are vaguely disappointing in that respect. I love how the C++ folks gleefully pile complexity on top of glittering complexity. But when it comes time to actually get some work done ... then maybe you want something simpler. (Especially when the wondrous pyramid is built on unsafe ground.)
Complexity also tends to affect build times. C++ and Scala are both known for slow compiles, whereas Go is extremely fast.
Unfortunately, from what I can see of Scala Native it's not very mature. It's currently using the a conservative Boehm garbage collector. That's what I use in cSuneido and from experience I know the weaknesses of conservative garbage collection. It's definitely not as strong as the JVM garbage collector. But they are working on a new garbage collector. Go (and Mono) also started out weak in this area but improved greatly. I can't tell whether Scala Native has the same libraries (e.g. collections) as regular Scala. The libraries are (mostly?) written in Scala so I would hope they would be portable.
Scala Native also appears to be weak in the concurrency area, which seems like a fatal flaw in today's multi-core world.
One feature mentioned on the web site is that Scala Native provides access to malloc and realloc. While this might appear attractive to C programmers, it seems a little odd in a garbage collected language. It also allows you to explicitly allocate data on the stack (like alloca). I'd much rather have escape analysis (like Go) that does that automatically. (I did see a mention that they are working on escape analysis.)
I'm not sure if it's indicative of the project as a whole, but the PragProg book seems focused on writing unsafe C code in Scala syntax. Personally, I have no desire to go back to the days of buffer overflows and mysterious crashes from dangling pointers and memory access violations. It might give higher performance, but I suspect you'd get similar performance from writing it in safe Go.
It's an interesting project that I plan to keep an eye on, but I don't think it's ready for my use yet.
Scala is an attractive language. Scala is to Java as C++ is to C. Meaning it's much more complex. (Scala promotes its simple syntax, but that doesn't mean it's a simple language.)
In some ways I like Kotlin better than Scala. It seems to give a lot of the advantages of Scala, without Scala's complexity. And there are non-JVM versions of Kotlin. But the problem is that Kotlin relies on the Java libraries, which is a portability problem for the non-JVM versions. Whereas, one of the strengths of Scala is its libraries (e.g. collections).
Libraries bring up an interesting issue. To write good libraries seems to require more features and complexity than application code. A lot of the complexity of C++ is to enable writing good libraries, and I suspect the same is true of Scala. The other alternative is the Go approach. Go has a built in "map" collection. You can't write map in the Go language. If you want a slightly different style of map, what you can write in Go is nothing like the built in one. This is at the heart of the Go generics struggle. On one hand, you want to be able to write your own map in Go. On the other hand, you want to keep Go's simplicity and not end up with another C++.
Another factor is that people seem to like complexity, regardless of whether it's counter-productive, myself included, sadly. Languages like C++ are fascinating. There's always something more you can learn. Whereas simpler languages like Go are vaguely disappointing in that respect. I love how the C++ folks gleefully pile complexity on top of glittering complexity. But when it comes time to actually get some work done ... then maybe you want something simpler. (Especially when the wondrous pyramid is built on unsafe ground.)
Complexity also tends to affect build times. C++ and Scala are both known for slow compiles, whereas Go is extremely fast.
Unfortunately, from what I can see of Scala Native it's not very mature. It's currently using the a conservative Boehm garbage collector. That's what I use in cSuneido and from experience I know the weaknesses of conservative garbage collection. It's definitely not as strong as the JVM garbage collector. But they are working on a new garbage collector. Go (and Mono) also started out weak in this area but improved greatly. I can't tell whether Scala Native has the same libraries (e.g. collections) as regular Scala. The libraries are (mostly?) written in Scala so I would hope they would be portable.
Scala Native also appears to be weak in the concurrency area, which seems like a fatal flaw in today's multi-core world.
One feature mentioned on the web site is that Scala Native provides access to malloc and realloc. While this might appear attractive to C programmers, it seems a little odd in a garbage collected language. It also allows you to explicitly allocate data on the stack (like alloca). I'd much rather have escape analysis (like Go) that does that automatically. (I did see a mention that they are working on escape analysis.)
I'm not sure if it's indicative of the project as a whole, but the PragProg book seems focused on writing unsafe C code in Scala syntax. Personally, I have no desire to go back to the days of buffer overflows and mysterious crashes from dangling pointers and memory access violations. It might give higher performance, but I suspect you'd get similar performance from writing it in safe Go.
It's an interesting project that I plan to keep an eye on, but I don't think it's ready for my use yet.
No comments:
Post a Comment