Add possibility to execute code at any stage

examples/test.lua

@@ -1,4 +1,4 @@
-local b = 5
+global b = 5
 
 function add(x)
     return function (y)

src/compile.rs

@@ -73,8 +73,8 @@ impl LocalCounter {
 }
 
 impl Block {
-    pub fn find_constants(&self, scope: &mut Scope) -> HashSet<Constant> {
-        let mut constants = HashSet::new();
+    pub fn find_constants(&self, scope: &mut Scope, constants: Vec<Constant>) -> HashSet<Constant> {
+        let mut constants = constants.iter().cloned().collect::<HashSet<_>>();
 
         let mut inner_scope = scope.clone();
 
@@ -132,7 +132,7 @@ impl Statement {
             Statement::If(cond, then) => {
                 let mut constants = HashSet::new();
                 constants.extend(cond.kind.find_constants(scope));
-                constants.extend(then.find_constants(scope));
+                constants.extend(then.find_constants(scope, Vec::new()));
                 constants
             }
             Statement::Expression(expr) => expr.kind.find_constants(scope),
@@ -303,7 +303,7 @@ impl Expression {
                 constants
             }
             Expression::UnOp(_, expr) => expr.kind.find_constants(scope),
-            Expression::FunctionDefinition(_, block) => block.find_constants(scope),
+            Expression::FunctionDefinition(_, block) => block.find_constants(scope, Vec::new()),
             Expression::FunctionCall(expr, params) => {
                 let mut constants = HashSet::new();
                 constants.extend(expr.kind.find_constants(scope));

src/main.rs

@@ -40,40 +40,53 @@ impl RustFunction for Print {
     }
 }
 
-fn main() {
+fn compile(
+    text: &str,
+    constants: Vec<vm::Constant>,
+    prototypes: Vec<Vec<vm::Instruction>>,
+) -> (Vec<vm::Instruction>, compile::State, Vec<vm::Constant>) {
     let file_path = PathBuf::from("../examples/test.lua");
-    let tokens = tokenize(TEST).unwrap();
+    let tokens = tokenize(text).unwrap();
     let mut stream = TokenStream::from(&file_path, &tokens);
 
-    dbg!(&tokens);
+    // dbg!(&tokens);
 
     let chunk = stream.parse::<Block>().unwrap();
     stream.expect(Token::Eof).unwrap();
 
-    dbg!(&chunk);
+    // dbg!(&chunk);
 
     let constants = chunk
-        .find_constants(&mut Default::default())
+        .find_constants(&mut Default::default(), constants)
         .into_iter()
         .collect::<Vec<_>>();
-    dbg!(&constants);
 
     let mut state = compile::State {
         constants: constants.clone(),
-        prototypes: Vec::new(),
+        prototypes,
     };
     let mut scope = Default::default();
     let instructions = chunk.compile(&mut state, &mut scope);
 
+    (instructions, state, constants)
+}
+
+fn main() {
+    let (instructions, state, constants) = compile(TEST, Vec::new(), Vec::new());
+
+    dbg!(&instructions);
+
+    dbg!(&constants);
+
     let mut vm = VirtualMachine {
         environment: Default::default(),
-        constants,
+        constants: constants.clone(),
         prototypes: Default::default(),
         proto_counter: 0,
     };
     let chunk_id = vm.new_prototype(instructions);
-    for prototype in state.prototypes {
-        vm.new_prototype(prototype);
+    for prototype in &state.prototypes {
+        vm.new_prototype(prototype.clone());
     }
     dbg!(&vm.prototypes);
 
@@ -90,7 +103,24 @@ fn main() {
 
     let mut run = closure.run(Vec::new());
 
-    while run.next().unwrap().is_none() {}
+    while run.next().unwrap().is_none() {
+        let (instructions, state, constants) =
+            compile("print(b)", constants.clone(), state.prototypes.clone());
+
+        // dbg!(&instructions);
+
+        let mut new_run = run.execute(instructions, state, constants);
+        while {
+            match new_run.next() {
+                Ok(Some(_)) => false,
+                Ok(None) => true,
+                Err(e) => {
+                    print!("Error: {}", e);
+                    false
+                }
+            }
+        } {}
+    }
 
     dbg!(&vm.environment.borrow().globals);
 }

src/vm.rs

@@ -2,7 +2,10 @@ use thiserror::Error;
 
 use std::{cell::RefCell, collections::HashMap, fmt::Debug, rc::Rc};
 
-use crate::ast::{BinaryOperator, LuaNumber, UnaryOperator};
+use crate::{
+    ast::{BinaryOperator, LuaNumber, UnaryOperator},
+    compile,
+};
 
 pub type VMNumber = u64;
 
@@ -106,6 +109,8 @@ pub enum RuntimeError {
     InvalidOperand(UnaryOperator, Value),
     #[error("Tried calling a non-function: {0:?}")]
     TriedCallingNonFunction(Value),
+    #[error("Global not found: {0:?}")]
+    GlobalNotFound(Option<Constant>),
     #[error("{0}")]
     Custom(String),
 }
@@ -321,6 +326,44 @@ impl ClosureRunner {
         }
     }
 
+    fn close_upvalues(&self) -> HashMap<u16, Rc<RefCell<Value>>> {
+        let highest_upvalue = self
+            .closure
+            .upvalues
+            .iter()
+            .map(|(v, _)| *v)
+            .max()
+            .unwrap_or(0);
+
+        let mut upvalues = self.closure.upvalues.clone();
+        for (reg, value) in &self.stack {
+            upvalues.insert(reg + highest_upvalue + 1, value.clone());
+        }
+        upvalues
+    }
+
+    pub fn execute(
+        &mut self,
+        instructions: Vec<Instruction>,
+        state: compile::State,
+        constants: Vec<Constant>,
+    ) -> ClosureRunner {
+        let mut vm = self.closure.vm.clone();
+        vm.constants = constants;
+        let proto_id = vm.new_prototype(instructions);
+        for prototype in state.prototypes {
+            vm.new_prototype(prototype);
+        }
+
+        let closure = Closure {
+            vm,
+            prototype: proto_id,
+            environment: self.closure.environment.clone(),
+            upvalues: self.close_upvalues(),
+        };
+        closure.run(Vec::new())
+    }
+
     pub fn next(&mut self) -> Result<Option<Vec<Value>>, RuntimeError> {
         if let Some(inner) = &mut self.inner {
             match inner.next() {
@@ -408,7 +451,9 @@ impl ClosureRunner {
                     if let Some(global) = glob {
                         self.set_stack(*reg, global.clone());
                     } else {
-                        todo!("Global not found: {:?}", constants.get(*global as usize))
+                        return Err(RuntimeError::GlobalNotFound(
+                            constants.get(*global as usize).cloned(),
+                        ));
                     }
                 }
                 Instruction::GetUpVal(reg, upvalreg) => {
@@ -514,26 +559,13 @@ impl ClosureRunner {
                 }
                 Instruction::Close(_) => {}
                 Instruction::Closure(reg, protok) => {
-                    let highest_upvalue = self
-                        .closure
-                        .upvalues
-                        .iter()
-                        .map(|(v, _)| *v)
-                        .max()
-                        .unwrap_or(0);
-
-                    let mut upvalues = self.closure.upvalues.clone();
-                    for (reg, value) in &self.stack {
-                        upvalues.insert(reg + highest_upvalue + 1, value.clone());
-                    }
-
                     self.set_stack(
                         *reg,
                         Value::Function(Closure {
                             vm: self.closure.vm.clone(),
                             prototype: *protok,
                             environment: self.closure.environment.clone(),
-                            upvalues,
+                            upvalues: self.close_upvalues(),
                         }),
                     );
                 }