chore: rename executor -> evaluator and integrate into app

crates/eval/src/lib.rs

@@ -1,34 +1,43 @@
-use ir::instruction::Kind;
-use value::Dynamic;
+use ir::GraphIr;
 
-mod debug;
+mod kind;
 mod value;
 
-/// The available executors
-/// unused in early dev.
-#[derive(Debug, Clone, Copy, clap::ValueEnum)]
-pub enum RegisteredExecutor {
-    /// the debug executor is single threaded and really, *really* slow. And unstable. Don't use. Unless you're a dev working on this.
+/// Can collapse a [`GraphIr`] in meaningful ways and do interesting work on it.
+///
+/// It's surprisingly difficult to find a fitting description for this.
+pub trait Evaluator {
+    /// Take some [`GraphIr`] which will then be processed later.
+    /// May be called multiple times, in which the [`GraphIr`]s should add up.
+    // TODO: atm they definitely don't add up -- add some functionality to GraphIr to
+    //       make it combine two graphs into one
+    fn feed(&mut self, ir: GraphIr);
+
+    /// Walk through the _whole_ [`GraphIr`] and run through each instruction.
+    fn eval_full(&mut self);
+
+    // TODO: for an LSP or the like, eval_single which starts at a given instr
+}
+
+/// The available [`Evaluator`]s.
+///
+/// Checklist for adding new ones:
+///
+/// 1. Create a new module under the [`kind`] module.
+/// 2. Add a struct and implement [`Evaluator`] for it.
+#[derive(Clone, Copy, Debug, Default, clap::ValueEnum, serde::Deserialize, serde::Serialize)]
+pub enum Available {
+    /// Runs fully on the CPU. Single-threaded, debug-friendly and quick to implement.
+    #[default]
     Debug,
 }
 
-trait Executor {
-    fn execute(instruction: Kind, input: Option<Dynamic>) -> Option<Dynamic>;
-}
-
-pub fn execute_all(instructions: Vec<Kind>) {
-    let mut tmp = None;
-
-    for instruction in instructions {
-        tmp = debug::Executor::execute(instruction, tmp);
+impl Available {
+    /// Selects the [`Evaluator`] corresponding to this label.
+    #[must_use]
+    pub fn pick(&self) -> Box<dyn Evaluator> {
+        match self {
+            Self::Debug => Box::new(kind::debug::Evaluator::default()),
+        }
     }
 }
-
-// scratchpad lol:
-// execution structure:
-// 1. take in rpl
-// 2. analyse/validate structure against allowed executors
-// 3. assign executors to instructions
-// 4. optimize
-// 5. prepare memory management patterns
-// 6. run