Sphinx is a dynamically typed programming language that is inspired by Lua and Python, and implemented entirely in Rust!
Sphinx is not complete! It is in a pre-alpha state of development and there is still a lot to do before it is a fully functional language. Some things on my radar:
Sphynx is named after the cat, which is apparently actually spelled that way. And definitely not to avoid confusion with a well-known documentation generator.
My goal is to have a lightweight, expressive language. At the same time, I also want the language runtime to be reasonably fast.
As well, this whole project started as a way to learn Rust, and I have definitely been doing a lot of that. I would also love for this to be an actual, practical, and complete development tool for someone someday, and that's still a fairly long road to walk.
Sphinx is compiled to a bytecode intermediate representation which is run on a virtual machine. In the future I would like to move to a JIT implementation but there are a lot of other things to deal with first.
Sphinx makes use of Rust's pointer metadata API, which has not yet been stabilized. So in order to build it you will need nightly Rust. Probably if you're here you're interested in looking at the internals of a compiler/VM (since the language itself is pretty WIP), so you probably already know how to set that up, but if you don't, you can get it with rustup.
Once built, you can run the REPL with sphinx and the disassembler with sphinx-dasm. Both executables have --help to list the command line options.
Here is some example code you can run to get started: ```
fun make_inc() var a = 0 fun inc(s = 1) nonlocal a += s end end
fun fib(n) if n < 2 then return n end
fib(n - 2) + fib(n - 1)
end
let a, b, (var c, d), g, rest... = example("a", "b", "c", "d", "e", "f", "g") c += (d *= 2)
```
Right now sphinx will compile the code and execute it from memory. I plan to add support for binary bytecode input/output, but right now even the file format for that is TBD 🙃
I have an internal type system built around a MetaObject trait which makes it easy to specify the behaviours that are supported by each of the core primitive types in the language. Thanks to Rust's enum types (and some macros) this is implemented without any vtables, using runtime dispatch based on the enum discriminant.
Different representations of string data. Short strings are "inlined" on the stack when possible (inspired by flexstr). All strings that are used as identifiers are interned. Only strings >40 bytes long are allocated using the GC. The bytecode compiler converts local variable names into indexes into the value stack, so strings are not used at all when referencing local variables.
The Sphinx language uses a simple Mark-Trace GC inspired by rust-gc. The runtime itself does not use any GC. Since we are only GC'ing script data, a lot of the challenges that would be involved in writing a GC for general Rust code are avoided (that for example, rust-gc has to deal with).
The GC also supports allocating dynamically sized types without double-indirection (i.e. the Gc<T> smart pointer used for GCed data points directly to the DST, not a Box). It also uses thin pointers to refer to the dynamically sized allocation, which keeps the size of each Gc<T> down to a single usize. The GC also supports weak references!
In the future I would like to support incremental GC and maybe generational GC as well, but the current implementation is simple and works pretty well.
Because Sphinx is (mostly) implemented in Safe Rust, it should be possible to provide a completely safe FFI with Rust code. This would allow a host Rust application to gain the capabilities of an embedded dynamic scripting language.
As a long term goal I would like to also leverage the rlua bindings to provide a Lua FFI in Sphinx, as well.
At the present moment, nearly complete syntax highlighting is available for users of Sublime Text - just copy sphinx.sublime-syntax into your user packages directory. If you use a different text editor and want syntax highlighting for Sphinx, feel free to drop a request on GitHub. Getting the language working is my first priority, but I don't mind taking a look at it.
```
Block Comment
#{ Nested! }#
}#
print("Hello, world!")
"One"; "Two"
let immutable = "can't change me" var mutable = 0 print(mutable += 1) # almost all constructs in Sphinx are expressions
var annotated: Float = 3.14159 # not implemented yet, but someday...
"abc", 123
var first, second = "abc", "def" second, first = first, second assert "def", "abc" == first, second
{ value = 0xA } # anonymous object
Person { value = 0xC } # classy object
fun echo_default(thing = "default") print(thing) end
fun variadicfun(normalarg, variadic...) print(normalarg ) for variadicarg in variadic do print(variadic_arg) end end
variadic_fun("red", "blue", "green") # prints "red" then "blue" then "green"
configure_something({ option1 = true, option2 = false })
fun trace(wrapped) return fun(args...) print("trace") wrapped(args...) end end
@trace fun increment(x) return x + 1 end
```