917 lines
33 KiB
Rust
917 lines
33 KiB
Rust
//! Virtual machine and errors
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use std::{
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cmp::Ordering,
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fmt::{self, Display, Formatter},
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io,
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};
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use crate::{
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compile, instruction::*, AbstractValue, AnnotatedError, Argument, Chunk, ChunkError,
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ConcreteValue, Destination, DustError, Instruction, NativeFunctionError, Operation, Span,
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Value, ValueError, ValueRef,
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};
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pub fn run(source: &str) -> Result<Option<ConcreteValue>, DustError> {
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let chunk = compile(source)?;
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let mut vm = Vm::new(&chunk, None);
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vm.run()
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.map_err(|error| DustError::Runtime { error, source })
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}
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/// Dust virtual machine.
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///
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/// See the [module-level documentation](index.html) for more information.
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#[derive(Debug)]
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pub struct Vm<'a> {
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chunk: &'a Chunk,
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stack: Vec<Register>,
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parent: Option<&'a Vm<'a>>,
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local_definitions: Vec<Option<u16>>,
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ip: usize,
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last_assigned_register: Option<u16>,
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current_position: Span,
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}
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impl<'a> Vm<'a> {
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const STACK_LIMIT: usize = u16::MAX as usize;
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pub fn new(chunk: &'a Chunk, parent: Option<&'a Vm<'a>>) -> Self {
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Self {
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chunk,
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stack: Vec::new(),
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parent,
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local_definitions: vec![None; chunk.locals().len()],
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ip: 0,
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last_assigned_register: None,
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current_position: Span(0, 0),
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}
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}
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pub fn chunk(&self) -> &Chunk {
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self.chunk
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}
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pub fn current_position(&self) -> Span {
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self.current_position
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}
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pub fn run(&mut self) -> Result<Option<ConcreteValue>, VmError> {
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while let Ok(instruction) = self.read() {
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log::info!(
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"{} | {} | {} | {}",
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self.ip - 1,
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self.current_position,
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instruction.operation(),
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instruction.disassembly_info()
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);
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match instruction.operation() {
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Operation::Move => {
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let Move { from, to } = Move::from(&instruction);
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let from_register_has_value = self
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.stack
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.get(from as usize)
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.is_some_and(|register| !matches!(register, Register::Empty));
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let register = Register::Pointer(Pointer::Stack(from));
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if from_register_has_value {
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self.set_register(to, register)?;
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}
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}
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Operation::Close => {
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let Close { from, to } = Close::from(&instruction);
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if self.stack.len() < to as usize {
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return Err(VmError::StackUnderflow {
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position: self.current_position,
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});
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}
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for register_index in from..to {
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self.stack[register_index as usize] = Register::Empty;
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}
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}
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Operation::LoadBoolean => {
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let LoadBoolean {
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destination,
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value,
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jump_next,
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} = LoadBoolean::from(&instruction);
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let register_index = self.get_destination(destination)?;
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let boolean = ConcreteValue::Boolean(value).to_value();
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let register = Register::Value(boolean);
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self.set_register(register_index, register)?;
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if jump_next {
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self.jump(1, true);
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}
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}
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Operation::LoadConstant => {
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let LoadConstant {
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destination,
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constant_index,
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jump_next,
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} = LoadConstant::from(&instruction);
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let register_index = self.get_destination(destination)?;
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let register = Register::Pointer(Pointer::Constant(constant_index));
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self.set_register(register_index, register)?;
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if jump_next {
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self.ip += 1
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}
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}
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Operation::LoadList => {
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let LoadList {
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destination,
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start_register,
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} = LoadList::from(&instruction);
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let register_index = self.get_destination(destination)?;
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let mut pointers = Vec::new();
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for register in start_register..register_index {
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if let Some(Register::Empty) = self.stack.get(register as usize) {
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continue;
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}
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let pointer = Pointer::Stack(register);
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pointers.push(pointer);
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}
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let register =
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Register::Value(AbstractValue::List { items: pointers }.to_value());
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self.set_register(register_index, register)?;
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}
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Operation::LoadSelf => {
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let LoadSelf { destination } = LoadSelf::from(&instruction);
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let register_index = self.get_destination(destination)?;
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let register = Register::Value(AbstractValue::FunctionSelf.to_value());
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self.set_register(register_index, register)?;
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}
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Operation::DefineLocal => {
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let DefineLocal {
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register,
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local_index,
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is_mutable,
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} = DefineLocal::from(&instruction);
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self.local_definitions[local_index as usize] = Some(register);
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}
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Operation::GetLocal => {
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let GetLocal {
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destination,
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local_index,
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} = GetLocal::from(&instruction);
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let register_index = self.get_destination(destination)?;
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let local_register = self.local_definitions[local_index as usize].ok_or(
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VmError::UndefinedLocal {
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local_index,
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position: self.current_position,
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},
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)?;
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let register = Register::Pointer(Pointer::Stack(local_register));
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self.set_register(register_index, register)?;
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}
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Operation::SetLocal => {
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let SetLocal {
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register,
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local_index,
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} = SetLocal::from(&instruction);
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self.local_definitions[local_index as usize] = Some(register);
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}
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Operation::Add => {
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let Add {
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destination,
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left,
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right,
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} = Add::from(&instruction);
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let register_index = self.get_destination(destination)?;
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let left = self.get_argument(left)?;
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let right = self.get_argument(right)?;
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let sum = left.add(right).map_err(|error| VmError::Value {
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error,
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position: self.current_position,
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})?;
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self.set_register(register_index, Register::Value(sum))?;
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}
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Operation::Subtract => {
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let Subtract {
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destination,
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left,
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right,
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} = Subtract::from(&instruction);
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let register_index = self.get_destination(destination)?;
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let left = self.get_argument(left)?;
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let right = self.get_argument(right)?;
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let difference = left.subtract(right).map_err(|error| VmError::Value {
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error,
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position: self.current_position,
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})?;
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self.set_register(register_index, Register::Value(difference))?;
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}
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Operation::Multiply => {
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let Multiply {
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destination,
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left,
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right,
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} = Multiply::from(&instruction);
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let register_index = self.get_destination(destination)?;
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let left = self.get_argument(left)?;
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let right = self.get_argument(right)?;
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let product = left.multiply(right).map_err(|error| VmError::Value {
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error,
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position: self.current_position,
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})?;
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self.set_register(register_index, Register::Value(product))?;
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}
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Operation::Divide => {
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let Divide {
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destination,
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left,
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right,
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} = Divide::from(&instruction);
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let register_index = self.get_destination(destination)?;
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let left = self.get_argument(left)?;
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let right = self.get_argument(right)?;
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let quotient = left.divide(right).map_err(|error| VmError::Value {
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error,
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position: self.current_position,
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})?;
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self.set_register(register_index, Register::Value(quotient))?;
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}
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Operation::Modulo => {
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let Modulo {
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destination,
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left,
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right,
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} = Modulo::from(&instruction);
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let register_index = self.get_destination(destination)?;
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let left = self.get_argument(left)?;
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let right = self.get_argument(right)?;
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let remainder = left.modulo(right).map_err(|error| VmError::Value {
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error,
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position: self.current_position,
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})?;
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self.set_register(register_index, Register::Value(remainder))?;
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}
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Operation::Test => {
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let Test {
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argument,
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test_value,
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} = Test::from(&instruction);
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let value = self.get_argument(argument)?;
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let boolean = if let ValueRef::Concrete(ConcreteValue::Boolean(boolean)) = value
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{
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*boolean
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} else {
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return Err(VmError::ExpectedBoolean {
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found: value.to_owned(),
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position: self.current_position,
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});
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};
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if boolean == test_value {
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self.jump(1, true);
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}
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}
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Operation::TestSet => {
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let TestSet {
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destination,
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argument,
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test_value,
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} = TestSet::from(&instruction);
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let register_index = self.get_destination(destination)?;
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let value = self.get_argument(argument)?;
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let boolean = if let ValueRef::Concrete(ConcreteValue::Boolean(boolean)) = value
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{
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*boolean
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} else {
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return Err(VmError::ExpectedBoolean {
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found: value.to_owned(),
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position: self.current_position,
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});
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};
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if boolean == test_value {
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self.jump(1, true);
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} else {
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let pointer = match argument {
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Argument::Constant(constant_index) => Pointer::Constant(constant_index),
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Argument::Local(local_index) => {
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let register_index = self.local_definitions[local_index as usize]
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.ok_or(VmError::UndefinedLocal {
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local_index,
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position: self.current_position,
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})?;
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Pointer::Stack(register_index)
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}
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Argument::Register(register_index) => Pointer::Stack(register_index),
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};
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let register = Register::Pointer(pointer);
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self.set_register(register_index, register)?;
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}
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}
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Operation::Equal => {
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let Equal { value, left, right } = Equal::from(&instruction);
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let left = self.get_argument(left)?;
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let right = self.get_argument(right)?;
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let equal_result = left.equal(right).map_err(|error| VmError::Value {
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error,
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position: self.current_position,
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})?;
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let is_equal =
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if let Value::Concrete(ConcreteValue::Boolean(boolean)) = equal_result {
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boolean
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} else {
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return Err(VmError::ExpectedBoolean {
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found: equal_result,
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position: self.current_position,
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});
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};
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if is_equal == value {
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self.jump(1, true);
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} else {
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let jump = self.read()?;
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let Jump {
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offset,
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is_positive,
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} = Jump::from(&jump);
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self.jump(offset as usize, is_positive);
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}
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}
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Operation::Less => {
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let Less { value, left, right } = Less::from(&instruction);
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let left = self.get_argument(left)?;
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let right = self.get_argument(right)?;
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let less_result = left.less_than(right).map_err(|error| VmError::Value {
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error,
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position: self.current_position,
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})?;
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let is_less_than =
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if let Value::Concrete(ConcreteValue::Boolean(boolean)) = less_result {
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boolean
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} else {
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return Err(VmError::ExpectedBoolean {
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found: less_result,
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position: self.current_position,
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});
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};
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if is_less_than == value {
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self.jump(1, true);
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} else {
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let jump = self.read()?;
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let Jump {
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offset,
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is_positive,
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} = Jump::from(&jump);
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self.jump(offset as usize, is_positive);
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}
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}
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Operation::LessEqual => {
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let LessEqual { value, left, right } = LessEqual::from(&instruction);
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let left = self.get_argument(left)?;
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let right = self.get_argument(right)?;
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let less_or_equal_result =
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left.less_than_or_equal(right)
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.map_err(|error| VmError::Value {
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error,
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position: self.current_position,
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})?;
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let is_less_than_or_equal =
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if let Value::Concrete(ConcreteValue::Boolean(boolean)) =
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less_or_equal_result
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{
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boolean
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} else {
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return Err(VmError::ExpectedBoolean {
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found: less_or_equal_result,
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position: self.current_position,
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});
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};
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if is_less_than_or_equal == value {
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self.jump(1, true);
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} else {
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let jump = self.read()?;
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let Jump {
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offset,
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is_positive,
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} = Jump::from(&jump);
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self.jump(offset as usize, is_positive);
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}
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}
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Operation::Negate => {
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let Negate {
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destination,
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argument,
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} = Negate::from(&instruction);
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let value = self.get_argument(argument)?;
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let negated = value.negate().map_err(|error| VmError::Value {
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error,
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position: self.current_position,
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})?;
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let register_index = self.get_destination(destination)?;
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let register = Register::Value(negated);
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self.set_register(register_index, register)?;
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}
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Operation::Not => {
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let Not {
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destination,
|
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argument,
|
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} = Not::from(&instruction);
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let value = self.get_argument(argument)?;
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let not = value.not().map_err(|error| VmError::Value {
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error,
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position: self.current_position,
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})?;
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let register_index = self.get_destination(destination)?;
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let register = Register::Value(not);
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self.set_register(register_index, register)?;
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}
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Operation::Jump => {
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let jump = self.read()?;
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let Jump {
|
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offset,
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is_positive,
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} = Jump::from(&jump);
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self.jump(offset as usize, is_positive);
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}
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Operation::Call => {
|
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let Call {
|
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destination,
|
|
function,
|
|
argument_count,
|
|
} = Call::from(&instruction);
|
|
let register_index = self.get_destination(destination)?;
|
|
let function = self.get_argument(function)?;
|
|
let chunk = if let ValueRef::Concrete(ConcreteValue::Function(chunk)) = function
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{
|
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chunk
|
|
} else if let ValueRef::Abstract(AbstractValue::FunctionSelf) = function {
|
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self.chunk
|
|
} else {
|
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return Err(VmError::ExpectedFunction {
|
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found: function.to_concrete_owned(self)?,
|
|
position: self.current_position,
|
|
});
|
|
};
|
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let mut function_vm = Vm::new(chunk, Some(self));
|
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let first_argument_index = register_index - argument_count - 1;
|
|
|
|
for (argument_index, argument_register_index) in
|
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(first_argument_index..register_index).enumerate()
|
|
{
|
|
function_vm.set_register(
|
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argument_index as u16,
|
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Register::Pointer(Pointer::ParentStack(argument_register_index)),
|
|
)?;
|
|
|
|
function_vm
|
|
.local_definitions
|
|
.push(Some(argument_index as u16));
|
|
}
|
|
|
|
let return_value = function_vm.run()?;
|
|
|
|
if let Some(concrete_value) = return_value {
|
|
let register = Register::Value(concrete_value.to_value());
|
|
|
|
self.set_register(register_index, register)?;
|
|
}
|
|
}
|
|
Operation::CallNative => {
|
|
let CallNative {
|
|
destination,
|
|
function,
|
|
argument_count,
|
|
} = CallNative::from(&instruction);
|
|
let return_value = function.call(self, instruction)?;
|
|
|
|
if let Some(value) = return_value {
|
|
let register_index = self.get_destination(destination)?;
|
|
let register = Register::Value(value);
|
|
|
|
self.set_register(register_index, register)?;
|
|
}
|
|
}
|
|
Operation::Return => {
|
|
let Return {
|
|
should_return_value,
|
|
} = Return::from(&instruction);
|
|
|
|
if !should_return_value {
|
|
return Ok(None);
|
|
}
|
|
|
|
return if let Some(register_index) = self.last_assigned_register {
|
|
let return_value = self
|
|
.open_register(register_index)?
|
|
.to_concrete_owned(self)?;
|
|
|
|
Ok(Some(return_value))
|
|
} else {
|
|
Err(VmError::StackUnderflow {
|
|
position: self.current_position,
|
|
})
|
|
};
|
|
}
|
|
}
|
|
}
|
|
|
|
Ok(None)
|
|
}
|
|
|
|
pub(crate) fn follow_pointer(&self, pointer: Pointer) -> Result<ValueRef, VmError> {
|
|
match pointer {
|
|
Pointer::Stack(register_index) => self.open_register(register_index),
|
|
Pointer::Constant(constant_index) => {
|
|
let constant = self.get_constant(constant_index)?;
|
|
|
|
Ok(ValueRef::Concrete(constant))
|
|
}
|
|
Pointer::ParentStack(register_index) => {
|
|
let parent = self
|
|
.parent
|
|
.as_ref()
|
|
.ok_or_else(|| VmError::ExpectedParent {
|
|
position: self.current_position,
|
|
})?;
|
|
|
|
parent.open_register(register_index)
|
|
}
|
|
Pointer::ParentConstant(constant_index) => {
|
|
let parent = self
|
|
.parent
|
|
.as_ref()
|
|
.ok_or_else(|| VmError::ExpectedParent {
|
|
position: self.current_position,
|
|
})?;
|
|
let constant = parent.get_constant(constant_index)?;
|
|
|
|
Ok(ValueRef::Concrete(constant))
|
|
}
|
|
}
|
|
}
|
|
|
|
fn open_register(&self, register_index: u16) -> Result<ValueRef, VmError> {
|
|
let register_index = register_index as usize;
|
|
let register =
|
|
self.stack
|
|
.get(register_index)
|
|
.ok_or_else(|| VmError::RegisterIndexOutOfBounds {
|
|
index: register_index,
|
|
position: self.current_position,
|
|
})?;
|
|
|
|
log::trace!("Open R{register_index} to {register}");
|
|
|
|
match register {
|
|
Register::Value(value) => Ok(value.to_ref()),
|
|
Register::Pointer(pointer) => self.follow_pointer(*pointer),
|
|
Register::Empty => Err(VmError::EmptyRegister {
|
|
index: register_index,
|
|
position: self.current_position,
|
|
}),
|
|
}
|
|
}
|
|
|
|
pub(crate) fn open_register_allow_empty(
|
|
&self,
|
|
register_index: u16,
|
|
) -> Result<Option<ValueRef>, VmError> {
|
|
let register_index = register_index as usize;
|
|
let register =
|
|
self.stack
|
|
.get(register_index)
|
|
.ok_or_else(|| VmError::RegisterIndexOutOfBounds {
|
|
index: register_index,
|
|
position: self.current_position,
|
|
})?;
|
|
|
|
log::trace!("Open R{register_index} to {register}");
|
|
|
|
match register {
|
|
Register::Value(value) => Ok(Some(value.to_ref())),
|
|
Register::Pointer(pointer) => self.follow_pointer(*pointer).map(Some),
|
|
Register::Empty => Ok(None),
|
|
}
|
|
}
|
|
|
|
/// DRY helper for handling JUMP instructions
|
|
fn jump(&mut self, offset: usize, is_positive: bool) {
|
|
log::trace!(
|
|
"Jumping {}",
|
|
if is_positive {
|
|
format!("+{}", offset)
|
|
} else {
|
|
format!("-{}", offset + 1)
|
|
}
|
|
);
|
|
|
|
let new_ip = if is_positive {
|
|
self.ip + offset
|
|
} else {
|
|
self.ip - offset - 1
|
|
};
|
|
self.ip = new_ip;
|
|
}
|
|
|
|
/// DRY helper to get a register index from a Destination
|
|
fn get_destination(&self, destination: Destination) -> Result<u16, VmError> {
|
|
let index = match destination {
|
|
Destination::Register(register_index) => register_index,
|
|
Destination::Local(local_index) => self
|
|
.local_definitions
|
|
.get(local_index as usize)
|
|
.copied()
|
|
.flatten()
|
|
.ok_or_else(|| VmError::UndefinedLocal {
|
|
local_index,
|
|
position: self.current_position,
|
|
})?,
|
|
};
|
|
|
|
Ok(index)
|
|
}
|
|
|
|
/// DRY helper to get a value from an Argument
|
|
fn get_argument(&self, argument: Argument) -> Result<ValueRef, VmError> {
|
|
let value_ref = match argument {
|
|
Argument::Constant(constant_index) => {
|
|
ValueRef::Concrete(self.get_constant(constant_index)?)
|
|
}
|
|
Argument::Register(register_index) => self.open_register(register_index)?,
|
|
Argument::Local(local_index) => self.get_local(local_index)?,
|
|
};
|
|
|
|
Ok(value_ref)
|
|
}
|
|
|
|
fn set_register(&mut self, to_register: u16, register: Register) -> Result<(), VmError> {
|
|
self.last_assigned_register = Some(to_register);
|
|
|
|
let length = self.stack.len();
|
|
let to_register = to_register as usize;
|
|
|
|
if length == Self::STACK_LIMIT {
|
|
return Err(VmError::StackOverflow {
|
|
position: self.current_position,
|
|
});
|
|
}
|
|
|
|
match to_register.cmp(&length) {
|
|
Ordering::Less => {
|
|
log::trace!("Change R{to_register} to {register}");
|
|
|
|
self.stack[to_register] = register;
|
|
|
|
Ok(())
|
|
}
|
|
Ordering::Equal => {
|
|
log::trace!("Set R{to_register} to {register}");
|
|
|
|
self.stack.push(register);
|
|
|
|
Ok(())
|
|
}
|
|
Ordering::Greater => {
|
|
let difference = to_register - length;
|
|
|
|
for index in 0..difference {
|
|
log::trace!("Set R{index} to {register}");
|
|
|
|
self.stack.push(Register::Empty);
|
|
}
|
|
|
|
log::trace!("Set R{to_register} to {register}");
|
|
|
|
self.stack.push(register);
|
|
|
|
Ok(())
|
|
}
|
|
}
|
|
}
|
|
|
|
fn get_constant(&self, constant_index: u16) -> Result<&ConcreteValue, VmError> {
|
|
self.chunk
|
|
.get_constant(constant_index)
|
|
.map_err(|error| VmError::Chunk {
|
|
error,
|
|
position: self.current_position,
|
|
})
|
|
}
|
|
|
|
fn get_local(&self, local_index: u16) -> Result<ValueRef, VmError> {
|
|
let register_index = self
|
|
.local_definitions
|
|
.get(local_index as usize)
|
|
.ok_or_else(|| VmError::UndefinedLocal {
|
|
local_index,
|
|
position: self.current_position,
|
|
})?
|
|
.ok_or_else(|| VmError::UndefinedLocal {
|
|
local_index,
|
|
position: self.current_position,
|
|
})?;
|
|
|
|
self.open_register(register_index)
|
|
}
|
|
|
|
fn read(&mut self) -> Result<Instruction, VmError> {
|
|
let (instruction, _type, position) =
|
|
self.chunk
|
|
.get_instruction(self.ip)
|
|
.map_err(|error| VmError::Chunk {
|
|
error,
|
|
position: self.current_position,
|
|
})?;
|
|
|
|
self.jump(1, true);
|
|
self.current_position = *position;
|
|
|
|
Ok(*instruction)
|
|
}
|
|
}
|
|
|
|
#[derive(Clone, Debug, PartialEq)]
|
|
pub enum Register {
|
|
Empty,
|
|
Value(Value),
|
|
Pointer(Pointer),
|
|
}
|
|
|
|
impl Display for Register {
|
|
fn fmt(&self, f: &mut Formatter) -> fmt::Result {
|
|
match self {
|
|
Self::Empty => write!(f, "empty"),
|
|
Self::Value(value) => write!(f, "{}", value),
|
|
Self::Pointer(pointer) => write!(f, "{}", pointer),
|
|
}
|
|
}
|
|
}
|
|
|
|
#[derive(Clone, Copy, Debug, Eq, PartialEq, PartialOrd, Ord)]
|
|
pub enum Pointer {
|
|
Stack(u16),
|
|
Constant(u16),
|
|
ParentStack(u16),
|
|
ParentConstant(u16),
|
|
}
|
|
|
|
impl Display for Pointer {
|
|
fn fmt(&self, f: &mut Formatter) -> fmt::Result {
|
|
match self {
|
|
Self::Stack(index) => write!(f, "R{}", index),
|
|
Self::Constant(index) => write!(f, "C{}", index),
|
|
Self::ParentStack(index) => write!(f, "PR{}", index),
|
|
Self::ParentConstant(index) => write!(f, "PC{}", index),
|
|
}
|
|
}
|
|
}
|
|
|
|
#[derive(Clone, Debug, PartialEq)]
|
|
pub enum VmError {
|
|
// Stack errors
|
|
StackOverflow {
|
|
position: Span,
|
|
},
|
|
StackUnderflow {
|
|
position: Span,
|
|
},
|
|
|
|
// Register errors
|
|
EmptyRegister {
|
|
index: usize,
|
|
position: Span,
|
|
},
|
|
ExpectedConcreteValue {
|
|
found: AbstractValue,
|
|
position: Span,
|
|
},
|
|
ExpectedValue {
|
|
found: Register,
|
|
position: Span,
|
|
},
|
|
RegisterIndexOutOfBounds {
|
|
index: usize,
|
|
position: Span,
|
|
},
|
|
|
|
// Local errors
|
|
UndefinedLocal {
|
|
local_index: u16,
|
|
position: Span,
|
|
},
|
|
|
|
// Execution errors
|
|
ExpectedBoolean {
|
|
found: Value,
|
|
position: Span,
|
|
},
|
|
ExpectedFunction {
|
|
found: ConcreteValue,
|
|
position: Span,
|
|
},
|
|
ExpectedParent {
|
|
position: Span,
|
|
},
|
|
ValueDisplay {
|
|
error: io::ErrorKind,
|
|
position: Span,
|
|
},
|
|
|
|
// Wrappers for foreign errors
|
|
Chunk {
|
|
error: ChunkError,
|
|
position: Span,
|
|
},
|
|
NativeFunction(NativeFunctionError),
|
|
Value {
|
|
error: ValueError,
|
|
position: Span,
|
|
},
|
|
}
|
|
|
|
impl AnnotatedError for VmError {
|
|
fn title() -> &'static str {
|
|
"Runtime Error"
|
|
}
|
|
|
|
fn description(&self) -> &'static str {
|
|
match self {
|
|
Self::Chunk { .. } => "Chunk error",
|
|
Self::EmptyRegister { .. } => "Empty register",
|
|
Self::ExpectedBoolean { .. } => "Expected boolean",
|
|
Self::ExpectedConcreteValue { .. } => "Expected concrete value",
|
|
Self::ExpectedFunction { .. } => "Expected function",
|
|
Self::ExpectedParent { .. } => "Expected parent",
|
|
Self::ExpectedValue { .. } => "Expected value",
|
|
Self::NativeFunction(error) => error.description(),
|
|
Self::RegisterIndexOutOfBounds { .. } => "Register index out of bounds",
|
|
Self::StackOverflow { .. } => "Stack overflow",
|
|
Self::StackUnderflow { .. } => "Stack underflow",
|
|
Self::UndefinedLocal { .. } => "Undefined local",
|
|
Self::Value { .. } => "Value error",
|
|
Self::ValueDisplay { .. } => "Value display error",
|
|
}
|
|
}
|
|
|
|
fn details(&self) -> Option<String> {
|
|
match self {
|
|
Self::Chunk { error, .. } => Some(error.to_string()),
|
|
Self::EmptyRegister { index, .. } => Some(format!("Register R{index} is empty")),
|
|
Self::ExpectedFunction { found, .. } => Some(format!("{found} is not a function")),
|
|
|
|
Self::RegisterIndexOutOfBounds { index, .. } => {
|
|
Some(format!("Register {index} does not exist"))
|
|
}
|
|
Self::NativeFunction(error) => error.details(),
|
|
Self::Value { error, .. } => Some(error.to_string()),
|
|
Self::ValueDisplay { error, .. } => Some(error.to_string() + " while displaying value"),
|
|
_ => None,
|
|
}
|
|
}
|
|
|
|
fn position(&self) -> Span {
|
|
match self {
|
|
Self::Chunk { position, .. } => *position,
|
|
Self::EmptyRegister { position, .. } => *position,
|
|
Self::ExpectedBoolean { position, .. } => *position,
|
|
Self::ExpectedConcreteValue { position, .. } => *position,
|
|
Self::ExpectedFunction { position, .. } => *position,
|
|
Self::ExpectedParent { position } => *position,
|
|
Self::ExpectedValue { position, .. } => *position,
|
|
Self::NativeFunction(error) => error.position(),
|
|
Self::RegisterIndexOutOfBounds { position, .. } => *position,
|
|
Self::StackOverflow { position } => *position,
|
|
Self::StackUnderflow { position } => *position,
|
|
Self::UndefinedLocal { position, .. } => *position,
|
|
Self::Value { position, .. } => *position,
|
|
Self::ValueDisplay { position, .. } => *position,
|
|
}
|
|
}
|
|
}
|