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Add a GC (#21)

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2
Cargo.toml
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@ -6,8 +6,6 @@ edition = "2021"
[dependencies]
logos = "0.12.0"
ariadne = { git = "https://github.com/zesterer/ariadne", rev = "689782a3531c3d4a3e53af998b059c733729c42e" }
either = "1.6.1"
hexponent = "0.3.1"
[dev-dependencies]
insta = "1.10.0"

201
LICENSE Normal file
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@ -0,0 +1,201 @@
Apache License
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5
README.md
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@ -23,3 +23,8 @@ We do not support the following Lua 5.4 features:
- `goto` statements and labels
- `\z` string literal escapes
- function calls without parentheses
## License
Zaia is licensed under the Apache v2.0 license.
See LICENSE for more information.

45
src/engine/gc/handle.rs Normal file
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@ -0,0 +1,45 @@
use std::{cmp, hash};
pub struct Handle<T> {
ptr: *mut T,
}
impl<T> Handle<T> {
pub fn new(ptr: *mut T) -> Self {
Handle { ptr }
}
pub unsafe fn get_unchecked<'a>(self) -> &'a T {
&*self.ptr
}
pub unsafe fn get_unchecked_mut<'a>(self) -> &'a mut T {
&mut *self.ptr
}
pub unsafe fn destroy(self) {
Box::from_raw(self.ptr);
}
}
impl<T> Clone for Handle<T> {
fn clone(&self) -> Self {
Handle { ptr: self.ptr }
}
}
impl<T> Copy for Handle<T> {}
impl<T> cmp::PartialEq for Handle<T> {
fn eq(&self, other: &Self) -> bool {
self.ptr == other.ptr
}
}
impl<T> cmp::Eq for Handle<T> {}
impl<T> hash::Hash for Handle<T> {
fn hash<H: hash::Hasher>(&self, state: &mut H) {
self.ptr.hash(state);
}
}

49
src/engine/gc/heuristics.rs Normal file
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@ -0,0 +1,49 @@
use std::cell::Cell;
use super::{trace::Trace, Heap};
const INITIAL_THRESHOLD: usize = 128 * 1024;
const THRESHOLD_FACTOR: f32 = 1.75;
pub struct Heuristics {
allocated: Cell<usize>,
threshold: Cell<usize>,
in_cycle: Cell<bool>,
}
impl Heuristics {
pub fn new() -> Self {
Self {
allocated: Cell::new(0),
threshold: Cell::new(INITIAL_THRESHOLD),
in_cycle: Cell::new(false),
}
}
fn threshold(&self) -> usize {
(self.threshold.get() as f32 * THRESHOLD_FACTOR) as usize
}
fn check_collect<T, B>(&self, heap: &Heap<T, B>)
where
B: Trace<T>,
{
if !self.in_cycle.get() && self.allocated >= self.threshold {
self.in_cycle.set(true);
heap.collect();
self.in_cycle.set(false);
let new_threshold = self.threshold();
self.threshold.set(new_threshold);
}
}
pub fn update_allocated<T, B, F>(&self, heap: &Heap<T, B>, f: F)
where
B: Trace<T>,
F: FnOnce(usize) -> usize,
{
self.allocated.update(f);
self.check_collect(heap);
}
}

141
src/engine/gc/mod.rs Normal file
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@ -0,0 +1,141 @@
mod handle;
mod heuristics;
mod trace;
use std::{alloc, cell::RefCell, collections::HashSet, ptr, rc::Rc};
pub use handle::Handle;
use heuristics::Heuristics;
pub use trace::{Trace, Visitor};
#[derive(Clone)]
pub struct Heap<T, B> {
internal: Rc<HeapInternal<T, B>>,
}
impl<T, B> Heap<T, B>
where
B: Trace<T>,
{
pub fn new(base: B) -> Self {
Heap {
internal: Rc::new(HeapInternal::new(base)),
}
}
pub fn insert(&self, value: T) -> Handle<T> {
self.internal.insert(value)
}
pub fn collect(&self) {
self.internal.collect();
}
}
struct Tree<T> {
objects: HashSet<Handle<T>>,
visitor: Visitor<T>,
}
struct HeapInternal<T, B> {
heuristics: Heuristics,
tree: RefCell<Tree<T>>,
base: B,
}
impl<T, B> HeapInternal<T, B>
where
B: Trace<T>,
{
fn new(base: B) -> Self {
let tree = RefCell::new(Tree {
objects: HashSet::new(),
visitor: Visitor::new(),
});
Self {
heuristics: Heuristics::new(),
tree,
base,
}
}
fn insert(&self, value: T) -> Handle<T> {
let ptr = Box::into_raw(Box::new(value));
let handle = Handle::new(ptr);
self.tree.borrow_mut().objects.insert(handle);
handle
}
fn collect(&self) {
let mut tree = self.tree.borrow_mut();
tree.visitor.run(&self.base);
for object in tree.visitor.unmarked(&tree.objects) {
unsafe {
object.destroy();
}
}
tree.visitor.reset();
}
}
unsafe impl<T, B> alloc::Allocator for Heap<T, B>
where
B: Trace<T>,
{
fn allocate(&self, layout: alloc::Layout) -> Result<ptr::NonNull<[u8]>, alloc::AllocError> {
self.internal
.heuristics
.update_allocated(self, |x| x + layout.size());
alloc::Global.allocate(layout)
}
unsafe fn deallocate(&self, ptr: ptr::NonNull<u8>, layout: alloc::Layout) {
self.internal
.heuristics
.update_allocated(self, |x| x - layout.size());
alloc::Global.deallocate(ptr, layout)
}
unsafe fn grow(
&self,
ptr: ptr::NonNull<u8>,
old_layout: alloc::Layout,
new_layout: alloc::Layout,
) -> Result<ptr::NonNull<[u8]>, alloc::AllocError> {
self.internal
.heuristics
.update_allocated(self, |x| x + new_layout.size() - old_layout.size());
alloc::Global.grow(ptr, old_layout, new_layout)
}
unsafe fn grow_zeroed(
&self,
ptr: ptr::NonNull<u8>,
old_layout: alloc::Layout,
new_layout: alloc::Layout,
) -> Result<ptr::NonNull<[u8]>, alloc::AllocError> {
self.internal
.heuristics
.update_allocated(self, |x| x + new_layout.size() - old_layout.size());
alloc::Global.grow_zeroed(ptr, old_layout, new_layout)
}
unsafe fn shrink(
&self,
ptr: ptr::NonNull<u8>,
old_layout: alloc::Layout,
new_layout: alloc::Layout,
) -> Result<ptr::NonNull<[u8]>, alloc::AllocError> {
self.internal
.heuristics
.update_allocated(self, |x| x + new_layout.size() - old_layout.size());
alloc::Global.shrink(ptr, old_layout, new_layout)
}
}

38
src/engine/gc/trace.rs Normal file
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@ -0,0 +1,38 @@
use std::collections::HashSet;
use super::handle::Handle;
pub trait Trace<T> {
fn visit(&self, visitor: &mut Visitor<T>);
}
pub struct Visitor<T> {
marked: HashSet<Handle<T>>,
}
impl<T> Visitor<T> {
pub fn new() -> Self {
Self {
marked: HashSet::new(),
}
}
pub fn mark(&mut self, handle: Handle<T>) {
self.marked.insert(handle);
}
pub fn run(&mut self, root: &dyn Trace<T>) {
root.visit(self);
}
pub fn unmarked<'a>(
&'a self,
objects: &'a HashSet<Handle<T>>,
) -> impl Iterator<Item = Handle<T>> + 'a {
objects.difference(&self.marked).copied()
}
pub fn reset(&mut self) {
self.marked.clear();
}
}

8
src/engine/mod.rs Normal file
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@ -0,0 +1,8 @@
mod gc;
mod value;
use value::Table;
pub struct Engine {
environment: Table,
}

92
src/engine/value.rs Normal file
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@ -0,0 +1,92 @@
use std::{cmp, collections::HashMap, hash};
use super::gc::Handle;
#[derive(Clone)]
pub enum Value {
Boolean(bool),
Integer(i32),
Float(f32),
String(Vec<u8>),
Ref(Handle<RefValue>),
}
impl cmp::PartialEq for Value {
fn eq(&self, other: &Value) -> bool {
match (self, other) {
(Value::Boolean(a), Value::Boolean(b)) => a == b,
(Value::Integer(a), Value::Integer(b)) => a == b,
(Value::Float(a), Value::Float(b)) => a == b,
(Value::String(a), Value::String(b)) => a == b,
(Value::Ref(a), Value::Ref(b)) => a == b,
_ => false,
}
}
}
impl cmp::Eq for Value {}
impl cmp::PartialOrd for Value {
fn partial_cmp(&self, other: &Value) -> Option<cmp::Ordering> {
match (self, other) {
(Value::Boolean(a), Value::Boolean(b)) => a.partial_cmp(b),
(Value::Integer(a), Value::Integer(b)) => a.partial_cmp(b),
(Value::Float(a), Value::Float(b)) => a.partial_cmp(b),
(Value::String(a), Value::String(b)) => a.partial_cmp(b),
(Value::Ref(_), Value::Ref(_)) => None,
_ => None,
}
}
}
impl cmp::Ord for Value {
fn cmp(&self, other: &Value) -> cmp::Ordering {
match (self, other) {
(Value::Boolean(a), Value::Boolean(b)) => a.cmp(b),
(Value::Integer(a), Value::Integer(b)) => a.cmp(b),
(Value::Float(a), Value::Float(b)) => float_cmp(*a, *b),
(Value::String(a), Value::String(b)) => a.cmp(b),
(Value::Ref(_), Value::Ref(_)) => cmp::Ordering::Equal,
_ => cmp::Ordering::Equal,
}
}
}
impl hash::Hash for Value {
fn hash<H: hash::Hasher>(&self, state: &mut H) {
match self {
Value::Boolean(a) => a.hash(state),
Value::Integer(a) => a.hash(state),
Value::Float(a) => a.to_ne_bytes().hash(state),
Value::String(ref a) => a.hash(state),
Value::Ref(ref a) => a.hash(state),
}
}
}
fn float_cmp(a: f32, b: f32) -> cmp::Ordering {
let convert = |f: f32| {
let i = f.to_bits();
let bit = 1 << (32 - 1);
if i & bit == 0 {
i | bit
} else {
!i
}
};
convert(a).cmp(&convert(b))
}
pub enum RefValue {
Function(Function),
Table(Table),
}
pub struct Function {
scope: HashMap<String, Value>,
}
pub struct Table {
inner: HashMap<Value, Value>,
}

5
src/lib.rs
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@ -1,3 +1,8 @@
#![feature(allocator_api)]
#![feature(cell_update)]
#![allow(dead_code)]
mod engine;
pub mod parser;
pub mod syntax_tree;
mod utf8;

398
src/parser/hex_float.rs Normal file
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@ -0,0 +1,398 @@
// This module is a giant mess. Hexadecimal floats suck to parse and everyone
// seems to do it differently. I'm not sure if this is the best way to do it,
// but it works.
//
// Thanks to Julia Scheaffer for coming up with the code this is based on.
// You will be remembered for your contribution to society.
use core::fmt;
#[derive(Debug)]
/// Indicates the preicsision of a conversion
pub enum ConversionResult<T> {
/// The conversion was precise and the result represents the original
/// exactly.
Precise(T),
/// The conversion was imprecise and the result is as close to the original
/// as possible.
Imprecise(T),
}
impl<T> ConversionResult<T> {
/// Convert the result to it's contained type.
pub fn inner(self) -> T {
match self {
ConversionResult::Precise(f) => f,
ConversionResult::Imprecise(f) => f,
}
}
}
/// Error type for parsing hexadecimal literals.
///
/// See the [`ParseErrorKind`](enum.ParseErrorKind.html) documentation for more
/// details about the kinds of errors and examples.
///
/// `ParseError` only implements `std::error::Error` when the `std` feature is
/// enabled.
#[derive(Clone, Copy, PartialEq, Eq, Debug)]
pub struct ParseError {
/// Kind of error
pub kind: ParseErrorKind,
/// Approximate index of the error in the source data. This will always be
/// an index to the source, except for when something is expected and
/// nothing is found, in this case, `index` will be the length of the input.
pub index: usize,
}
/// Kind of parsing error.
///
/// Used in [`ParseError`](struct.ParseError.html)
#[derive(Clone, Copy, PartialEq, Eq, Debug)]
pub enum ParseErrorKind {
/// No prefix was found. Hexadecimal literals must start with a "0x" or "0X"
/// prefix.
///
/// Example: `0.F`
MissingPrefix,
/// No digits were found. Hexadecimals literals must have digits before or
/// after the decimal point.
///
/// Example: `0x.` `0x.p1`
MissingDigits,
/// Hexadecimal literals with a "p" or "P" to indicate an float must have
/// an exponent.
///
/// Example: `0xb.0p` `0x1p-`
MissingExponent,
/// The exponent of a hexidecimal literal must fit into a signed 32-bit
/// integer.
///
/// Example: `0x1p3000000000`
ExponentOverflow,
/// The end of the literal was expected, but more bytes were found.
///
/// Example: `0x1.g`
MissingEnd,
}
impl ParseErrorKind {
fn at(self, index: usize) -> ParseError {
ParseError { kind: self, index }
}
}
impl fmt::Display for ParseError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self.kind {
ParseErrorKind::MissingPrefix => write!(f, "literal must have hex prefix"),
ParseErrorKind::MissingDigits => write!(f, "literal must have digits"),
ParseErrorKind::MissingExponent => write!(f, "exponent not present"),
ParseErrorKind::ExponentOverflow => write!(f, "exponent too large to fit in integer"),
ParseErrorKind::MissingEnd => {
write!(f, "extra bytes were found at the end of float literal")
},
}
}
}
impl std::error::Error for ParseError {}
/// Represents a floating point literal
///
/// This struct is a representation of the text, that can be used to convert to
/// both single- and double-precision floats.
///
/// `FloatLiteral` is not `Copy`-able because it contains a vector of the
/// digits from the source data.
#[derive(Debug, Clone)]
pub struct FloatLiteral {
is_positive: bool,
// These are the values of the digits, not the digits in ascii form.
digits: Vec<u8>,
decimal_offset: i32,
exponent: i32,
}
/// Get the byte index of the start of `sub_slice` in `master_slice`
fn get_cursed_index(master_slice: &[u8], sub_slice: &[u8]) -> usize {
(sub_slice.as_ptr() as usize).saturating_sub(master_slice.as_ptr() as usize)
}
impl FloatLiteral {
/// Convert the `self` to an `f32` or `f64` and return the precision of the
/// conversion.
pub fn convert<F: FPFormat>(self) -> ConversionResult<F> {
F::from_literal(self)
}
/// Parse a slice of bytes into a `FloatLiteral`.
///
/// This is based on hexadecimal floating constants in the C11
/// specification, section [6.4.4.2](http://port70.net/~nsz/c/c11/n1570.html#6.4.4.2).
pub fn from_bytes(data: &[u8]) -> Result<FloatLiteral, ParseError> {
let original_data = data;
let (is_positive, data) = match data.get(0) {
Some(b'+') => (true, &data[1..]),
Some(b'-') => (false, &data[1..]),
_ => (true, data),
};
let data = match data.get(0..2) {
Some(b"0X") | Some(b"0x") => &data[2..],
_ => return Err(ParseErrorKind::MissingPrefix.at(0)),
};
let (ipart, data) = consume_hex_digits(data);
let (fpart, data): (&[_], _) = if data.get(0) == Some(&b'.') {
let (fpart, data) = consume_hex_digits(&data[1..]);
(fpart, data)
} else {
(b"", data)
};
// Must have digits before or after the decimal point.
if fpart.is_empty() && ipart.is_empty() {
return Err(ParseErrorKind::MissingDigits.at(get_cursed_index(original_data, data)));
}
let (exponent, data) = match data.get(0) {
Some(b'P') | Some(b'p') => {
let data = &data[1..];
let sign_offset = match data.get(0) {
Some(b'+') | Some(b'-') => 1,
_ => 0,
};
let exponent_digits_offset = data[sign_offset..]
.iter()
.position(|&b| !matches!(b, b'0'..=b'9'))
.unwrap_or_else(|| data[sign_offset..].len());
if exponent_digits_offset == 0 {
return Err(
ParseErrorKind::MissingExponent.at(get_cursed_index(original_data, data))
);
}
// The exponent should always contain valid utf-8 beacuse it
// consumes a sign, and base-10 digits.
let exponent: i32 =
core::str::from_utf8(&data[..sign_offset + exponent_digits_offset])
.expect("exponent did not contain valid utf-8")
.parse()
.map_err(|_| {
ParseErrorKind::ExponentOverflow
.at(get_cursed_index(original_data, data))
})?;
(exponent, &data[sign_offset + exponent_digits_offset..])
},
_ => (0, data),
};
if !data.is_empty() {
return Err(ParseErrorKind::MissingEnd.at(get_cursed_index(original_data, data)));
}
let mut raw_digits = ipart.to_vec();
raw_digits.extend_from_slice(fpart);
let first_digit = raw_digits.iter().position(|&d| d != b'0');
let (digits, decimal_offset) = if let Some(first_digit) = first_digit {
// Unwrap is safe because there is at least one digit.
let last_digit = raw_digits.iter().rposition(|&d| d != b'0').unwrap();
let decimal_offset = (ipart.len() as i32) - (first_digit as i32);
// Trim off the leading zeros
raw_digits.truncate(last_digit + 1);
// Trim off the trailing zeros
raw_digits.drain(..first_digit);
// Convert all the digits from ascii to their values.
for item in raw_digits.iter_mut() {
*item = hex_digit_to_int(*item).unwrap();
}
(raw_digits, decimal_offset)
} else {
(Vec::new(), 0)
};
Ok(FloatLiteral {
is_positive,
digits,
decimal_offset,
exponent,
})
}
}
impl core::str::FromStr for FloatLiteral {
type Err = ParseError;
fn from_str(s: &str) -> Result<FloatLiteral, ParseError> {
FloatLiteral::from_bytes(s.as_bytes())
}
}
impl From<FloatLiteral> for f32 {
fn from(literal: FloatLiteral) -> f32 {
literal.convert().inner()
}
}
impl From<FloatLiteral> for f64 {
fn from(literal: FloatLiteral) -> f64 {
literal.convert().inner()
}
}
fn hex_digit_to_int(digit: u8) -> Option<u8> {
match digit {
b'0' => Some(0x0),
b'1' => Some(0x1),
b'2' => Some(0x2),
b'3' => Some(0x3),
b'4' => Some(0x4),
b'5' => Some(0x5),
b'6' => Some(0x6),
b'7' => Some(0x7),
b'8' => Some(0x8),
b'9' => Some(0x9),
b'a' | b'A' => Some(0xa),
b'b' | b'B' => Some(0xb),
b'c' | b'C' => Some(0xc),
b'd' | b'D' => Some(0xd),
b'e' | b'E' => Some(0xe),
b'f' | b'F' => Some(0xf),
_ => None,
}
}
fn consume_hex_digits(data: &[u8]) -> (&[u8], &[u8]) {
let i = data
.iter()
.position(|&b| hex_digit_to_int(b).is_none())
.unwrap_or(data.len());
data.split_at(i)
}
use core::ops;
macro_rules! impl_fpformat {
($fp_type:ty, $bits_type:ty, $exponent_bits: literal, $mantissa_bits: literal, $from_bits: expr, $infinity: expr, $max_exp: expr, $min_exp: expr) => {
impl FPFormat for $fp_type {
fn from_literal(literal: FloatLiteral) -> ConversionResult<$fp_type> {
const EXPONENT_BITS: u32 = $exponent_bits;
const MANTISSA_BITS: u32 = $mantissa_bits;
const TOTAL_BITS: u32 = 1 + EXPONENT_BITS + MANTISSA_BITS;
// The spec always gives an exponent bias that follows this formula.
const EXPONENT_BIAS: u32 = (1 << (EXPONENT_BITS - 1)) - 1;
// 4 bits for each hexadecimal offset
let mut exponent_offset: i32 = literal.decimal_offset * 4;
// If there were all
if literal.digits.is_empty() {
return ConversionResult::Precise(0.0);
}
// This code is a work of art.
let mut was_truncated = false;
let mut mantissa_result: $bits_type = 0;
for (index, digit) in literal.digits.iter().enumerate() {
if index as u32 * 4 > MANTISSA_BITS {
was_truncated = true;
break;
}
let mut digit_value = *digit as $bits_type;
digit_value <<= TOTAL_BITS - (index as u32 + 1) * 4;
mantissa_result |= digit_value;
}
let leading_zeros = mantissa_result.leading_zeros();
exponent_offset -= leading_zeros as i32 + 1;
mantissa_result <<= leading_zeros + 1;
mantissa_result >>= TOTAL_BITS - MANTISSA_BITS;
let final_exponent = exponent_offset + literal.exponent;
// Check for underflows
if final_exponent < $min_exp - 1 {
if literal.is_positive {
return ConversionResult::Imprecise(0.0);
} else {
return ConversionResult::Imprecise(-0.0);
};
}
// Check for overflows
if final_exponent > $max_exp - 1 {
if literal.is_positive {
return ConversionResult::Imprecise($infinity);
} else {
return ConversionResult::Imprecise(-$infinity);
};
}
let exponent_result: $bits_type =
((final_exponent + EXPONENT_BIAS as i32) as $bits_type) << MANTISSA_BITS;
let sign_result: $bits_type =
(!literal.is_positive as $bits_type) << (MANTISSA_BITS + EXPONENT_BITS);
let float_value = $from_bits(sign_result | exponent_result | mantissa_result);
if was_truncated {
ConversionResult::Imprecise(float_value)
} else {
ConversionResult::Precise(float_value)
}
// // This might be a bit faster.
// let mut final_result = !literal.is_positive as $bits_type;
// final_result <<= EXPONENT_BITS;
// final_result |= (final_exponent + EXPONENT_BIAS as i32) as
// $bits_type; final_result <<= MANTISSA_BITS;
// final_result |= mantissa_result;
// ConversionResult::Precise($from_bits(final_result))
}
}
};
}
/// Trait to describe conversion to floating point formats.
pub trait FPFormat: ops::Neg<Output = Self> + Sized + Copy {
/// Convert a literal to this format. This is a hack so that we can use
/// a macro to implement conversions.
fn from_literal(literal: FloatLiteral) -> ConversionResult<Self>;
}
impl_fpformat!(
f32,
u32,
8,
23,
f32::from_bits,
core::f32::INFINITY,
core::f32::MAX_EXP,
core::f32::MIN_EXP
);
impl_fpformat!(
f64,
u64,
11,
52,
f64::from_bits,
core::f64::INFINITY,
core::f64::MAX_EXP,
core::f64::MIN_EXP
);

29
src/parser/mod.rs
View file

@ -1,5 +1,6 @@
mod binding_power;
mod classifiers;
mod hex_float;
mod state;
mod token;
@ -12,7 +13,6 @@ use binding_power::{
INDEX_BINDING_POWER,
};
use classifiers::{token_is_expr_start, token_is_literal, token_to_binary_op, token_to_unary_op};
use either::Either;
use state::State;
use crate::{
@ -103,8 +103,8 @@ fn parse_stmt(state: &mut State) -> Stmt {
Stmt::If(item)
},
T![for] => match parse_for(state) {
Either::Left(numeric) => Stmt::ForNumeric(numeric),
Either::Right(generic) => Stmt::ForGeneric(generic),
For::Numeric(numeric) => Stmt::ForNumeric(numeric),
For::Generic(generic) => Stmt::ForGeneric(generic),
},
T![return] => {
let item = parse_return(state);
@ -459,16 +459,21 @@ fn parse_if(state: &mut State) -> If {
}
}
fn parse_for(state: &mut State) -> Either<ForNumeric, ForGeneric> {
enum For {
Numeric(ForNumeric),
Generic(ForGeneric),
}
fn parse_for(state: &mut State) -> For {
state.eat(T![for]);
let first_var = parse_ident(state);
if state.peek() == T![=] {
let item = parse_for_numeric(state, first_var);
Either::Left(item)
For::Numeric(item)
} else {
let item = parse_for_generic(state, first_var);
Either::Right(item)
For::Generic(item)
}
}
@ -765,27 +770,27 @@ fn parse_long_string(state: &mut State) -> Vec<u8> {
.into_bytes()
}
fn parse_int(state: &mut State) -> i64 {
fn parse_int(state: &mut State) -> i32 {
state.eat(T![int]);
state.slice().parse().unwrap()
}
fn parse_hex_int(state: &mut State) -> i64 {
fn parse_hex_int(state: &mut State) -> i32 {
state.eat(T![hex_int]);
let raw = &state.slice()[2..];
i64::from_str_radix(raw, 16).unwrap()
i32::from_str_radix(raw, 16).unwrap()
}
fn parse_float(state: &mut State) -> f64 {
fn parse_float(state: &mut State) -> f32 {
state.eat(T![float]);
state.slice().parse().unwrap()
}
fn parse_hex_float(state: &mut State) -> f64 {
fn parse_hex_float(state: &mut State) -> f32 {
state.eat(T![hex_float]);
let raw = state.slice();
hexponent::FloatLiteral::from_str(raw)
hex_float::FloatLiteral::from_str(raw)
.unwrap()
.convert()
.inner()

4
src/syntax_tree.rs
View file

@ -220,6 +220,6 @@ pub enum Literal {
#[derive(Debug, PartialEq)]
pub enum NumLiteral {
Int(i64),
Float(f64),
Int(i32),
Float(f32),
}