Added virtual machine and basic running

src/compiler.rs

@@ -4,10 +4,10 @@ use super::errors::CompilerError;
 use super::parser::{Expression, LiteralPattern, ParsedReid, Pattern, Position, Statement};
 
 type Variable = (HeapID, VariableType);
-type HeapID = u32;
+pub type HeapID = usize;
-type RegID = u32;
+pub type RegID = usize;
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub enum Command {
     InitializeVariable(HeapID, VariableType), // Initializes new variable to HeapID at VariableType
     BeginScope,                               // Begins new Scope

src/errors.rs

@@ -75,6 +75,7 @@ impl CompilerError {
         }
     }
 }
+
 impl Display for CompilerError {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         let text = match self {
@@ -83,7 +84,7 @@ impl Display for CompilerError {
                 format!("Variable '{}' already exists, re-assign at {}", pos, name)
             }
             CompilerError::VariableNotExists(pos, name) => {
-                format!("Variable '{}' does not exist, at {}", pos, name)
+                format!("Variable '{}' does not exist, at {}", name, pos)
             }
             CompilerError::InvalidScopeExit(pos) => {
                 format!("Attempted to escape a scope invalidly at {}", pos)
@@ -96,3 +97,15 @@ impl Display for CompilerError {
         write!(f, "{}", text)
     }
 }
+
+#[derive(Debug)]
+pub enum RuntimePanic {
+    Fatal,
+    InvalidCommandIdx(usize),
+    ScopeStackUnderflow,
+    StackUnderflow,
+    StackOverflow,
+    RegistryNotDefined,
+    InvalidHeapAddress,
+    ValueNotInitialized,
+}

src/main.rs

@@ -2,28 +2,33 @@ mod compiler;
 mod errors;
 mod file_io;
 mod parser;
+mod vm;
+
+use file_io::open_file;
+use std::path::Path;
 
 use compiler::Compiler;
-use file_io::open_file;
 use parser::Parser;
-use std::path::Path;
+use vm::VirtualMachine;
 
 fn main() {
     let path = Path::new("reid_src/test.reid");
     let parsed = Parser::from(open_file(&path).ok().unwrap()).parse();
-    match parsed {
+    if let Err(error) = parsed {
-        Err(error) => {
         eprintln!("Syntax error: {}", error);
         std::process::exit(1);
     }
-        Ok(parsed) => {
     dbg!(&parsed);
-            let compiled = Compiler::from(parsed).compile();
+    let compiled = Compiler::from(parsed.unwrap()).compile();
     if let Err(error) = compiled {
         eprintln!("Compilation error: {}", error);
         std::process::exit(1);
     }
-            dbg!(compiled);
+    dbg!(&compiled);
-        }
+
+    let mut vm = VirtualMachine::from(compiled.unwrap());
+    if let Err(error) = vm.run() {
+        eprintln!("Runtime panic: {:#?}", error);
+        std::process::exit(1);
     }
 }

src/vm.rs

@@ -0,0 +1,148 @@
+use std::collections::HashMap;
+
+use super::compiler::{Command, CompiledReid, HeapID, VariableType};
+use super::errors::RuntimePanic;
+
+pub struct VirtualMachine {
+    registry_stack: Vec<[Option<Value>; 8]>,
+    registry: [Option<Value>; 8],
+
+    stack: Vec<Value>,
+    heap: HashMap<HeapID, AllocatedVar>,
+
+    position: usize,
+    compiled: CompiledReid,
+}
+
+impl VirtualMachine {
+    pub fn from(compiled: CompiledReid) -> VirtualMachine {
+        VirtualMachine {
+            registry_stack: Vec::new(),
+            registry: Default::default(),
+
+            stack: Vec::new(),
+            heap: HashMap::new(),
+
+            position: 0,
+            compiled,
+        }
+    }
+
+    pub fn run(&mut self) -> Result<(), RuntimePanic> {
+        let mut error = None;
+        while error.is_none() {
+            if let Some(command) = self.compiled.list.get(self.position).map(|v| v.clone()) {
+                self.position += 1;
+                if let Err(err) = self.execute(command.clone()) {
+                    error = Some(err);
+                }
+                if self.remaining() == 0 {
+                    break;
+                }
+            } else {
+                error = Some(RuntimePanic::InvalidCommandIdx(self.position));
+            }
+        }
+
+        if let Some(error) = error {
+            Err(error)
+        } else {
+            Ok(())
+        }
+    }
+
+    fn remaining(&self) -> usize {
+        let len = self.compiled.list.len();
+        len - self.position.max(0).min(len)
+    }
+
+    fn execute(&mut self, command: Command) -> Result<(), RuntimePanic> {
+        match command {
+            Command::InitializeVariable(heapid, vtype) => {
+                self.heap.insert(heapid, AllocatedVar(vtype, None));
+                dbg!("Initialized new variable to heap", &self.heap);
+                Ok(())
+            }
+            Command::BeginScope => {
+                self.registry_stack.push(self.registry.clone());
+                self.registry = Default::default();
+                dbg!("Begun new scope");
+                Ok(())
+            }
+            Command::EndScope => {
+                if let Some(reg) = self.registry_stack.pop() {
+                    self.registry = reg;
+                    dbg!("Scope ended");
+                    Ok(())
+                } else {
+                    Err(RuntimePanic::ScopeStackUnderflow)
+                }
+            }
+            Command::Pop(regid) => {
+                if let Some(val) = self.stack.pop() {
+                    self.registry[regid] = Some(val);
+                    dbg!("Registry popped", regid, &self.stack, &self.registry);
+                    Ok(())
+                } else {
+                    Err(RuntimePanic::StackUnderflow)
+                }
+            }
+            Command::Push(regid) => {
+                if let Some(reg) = &self.registry[regid] {
+                    if self.stack.len() < usize::MAX {
+                        self.stack.push(reg.clone());
+                        dbg!("Registry pushed", regid, &self.stack);
+                        Ok(())
+                    } else {
+                        Err(RuntimePanic::StackOverflow)
+                    }
+                } else {
+                    Err(RuntimePanic::RegistryNotDefined)
+                }
+            }
+            Command::AssignVariable(heapid, regid) => {
+                if let Some(reg) = &self.registry[regid] {
+                    if let Some(var) = self.heap.get_mut(&heapid) {
+                        var.1 = Some(reg.clone());
+                        dbg!("Variable assigned", heapid, regid, &self.heap);
+                        Ok(())
+                    } else {
+                        Err(RuntimePanic::InvalidHeapAddress)
+                    }
+                } else {
+                    Err(RuntimePanic::RegistryNotDefined)
+                }
+            }
+            Command::VarToReg(heapid, regid) => {
+                if let Some(var) = self.heap.get(&heapid) {
+                    if let Some(val) = &var.1 {
+                        self.registry[regid] = Some(val.clone());
+                        dbg!("Variable pushed to registry", heapid, regid, &self.registry);
+                        Ok(())
+                    } else {
+                        Err(RuntimePanic::ValueNotInitialized)
+                    }
+                } else {
+                    Err(RuntimePanic::InvalidHeapAddress)
+                }
+            }
+            Command::StringLit(string) => {
+                if self.stack.len() < usize::MAX {
+                    self.stack.push(Value::StringVal(string.clone()));
+                    dbg!("String literal added to stack", string, &self.stack);
+                    Ok(())
+                } else {
+                    Err(RuntimePanic::StackOverflow)
+                }
+            }
+        }
+    }
+}
+
+#[derive(Clone, Debug)]
+struct AllocatedVar(VariableType, Option<Value>);
+
+#[derive(Clone, Debug)]
+enum Value {
+    StringVal(String),
+}