<li> Minimal, close to the metal Scheme (operate on words, bytes, vectors) as AST / core language
<li> Full Context-free (and eventually, context sensitive) reader macros using FUN-GLL (<atitle="fun-gll paper"href="https://www.sciencedirect.com/science/article/pii/S2590118420300058">FUN-GLL paper</a>) to extend language's syntax dynamically
<li> Implement Type Systems as Macros (<atitle="type systems as macros paper 1"href="http://www.ccs.neu.edu/home/stchang/pubs/ckg-popl2017.pdf">paper, up to System Fω</a>) (<atitle="type systems as macros paper 2"href="https://www.ccs.neu.edu/home/stchang/pubs/cbtb-popl2020.pdf">second paper, up to dependent types</a>)
<li> Use above macros to create richer language and embed entire other programming languages (syntax, semantics, and type system) for flawless interop/FFI (C, Go, Lua, JS, etc)
<li> File is interpreted, and then if "main" exists it is compiled, spidering backwards to referenced functions and data (Allows interpreted code to do metaprogramming, dependency resolution, generate code, etc, which is then compiled)
<li> Regionalized Value State Dependence Graph as backend-IR, enabling simpler implementations of powerful optimizations (<atitle="RSVDG paper"href="https://arxiv.org/pdf/1912.05036.pdf">RSVDG paper</a>) so that embedded languages have good preformance when compiled with little code
<p> Currently, I am bootstrapping this new core Lisp out of my prior compiler for my programming language, Kraken. I have implemented the first version of the FUN-GLL algorithm and have working context-free reader macros. I'll have enough to self-host this core soon, and will then use the more efficent core Lisp implementation to implement the Type Systems as Macros paper and add a type system to the new language.
<p> The general flow is that the input file is executed with the core Lisp interpreter, and if there is a "main" symbol defined the compiler emits C for that function & all other functions & data that it references. In this way the language supports very powerful meta-programming at compile time, including adding syntax to the language, arbitrary computation, and importing other files, and then compiles into a static executable. The current compiling backend emits C.
<p> Below are a few examples of using the live grammer modification / context-free reader macros to implement basic methods as well as embed the BF language into the core Lisp. The core Lisp implementation has been compiled to WebAssembly and should be able to run in your browser. Feel free to make edits and play around below.
<textareaid="hello_output">Output will appear here</textarea>
<aname="method_example"/>
<h4>Method Example:</h4>
Let's use our meta system (attaching objects to other objects) to implement basic objects/methods.
We will attach a vector of alternating symbols / functions (to make this example simple, since maps aren't built in) to our data as the meta, then look up methods on it when we preform a call. The add_grammer_rule function modifies the grammer/parser currently being used to parse the file and operates as a super-powerful reader macro. We use it in this code to add a rule that transforms <pre><code>a.b(c, d)</code></pre> into <pre><code>(method-call a 'b c d)</code></pre> where method-call is the function that looks up the symbol 'b on the meta object attached to a and calls it with the rest of the parameters.
; we can also have it compile into our main program (if this wasn't the web version)
(def! main (fn* () (do (println "BF: " (bf { ,>+++[<.>-] } [1337])) 0)))
</div>
<h4>Output: </h4>
<textareaid="bf_output">Output will appear here</textarea>
<aname="benchmarks"/>
<h3>Performance Benchmarks</h3>
<p>Performance is quite poor, as almost no work has gone into it as of yet.
We are currently focusing on the FUN-GLL macros and creating a more fully-featured language on top of the core Lisp using them. We will focus more on performance with the implemenation of the functional persistant datastructures and the self-hosting rewrite, and performance will be the main focus of the RVSDG IR part of the project.
<p> Even so, it is worth keeping a rough estimate of performance in mind. For this, we have compiled a very basic benchmark below, with more benchmark programs (sorting, etc) to be included as the language gets developed:
<br>
<table>
<thead>
<tr>
<th></th>
<th>Core Lisp Interpreter</th>
<th>Core Lisp Compiled to C</th>
<th>Hand-written C</th>
</tr>
</thead>
<tbody>
<tr>
<td><b>Fibonacci(27)</b></td>
<td>51.505s</td>
<td>0.007s</td>
<td>0.002s</td>
</tr>
</tbody>
</table>
<aname="next_steps"/>
<h3>Next Steps</h3>
<ul>
<li> Implement simple garbage collector for compiled code (currently C)
<li> Implement persistant functional data structures
