reid-llvm/reid/src/ast/parse.rs

1109 lines
40 KiB
Rust

use crate::ast::*;
use crate::lexer::Token;
use super::token_stream::{Error, TokenStream};
pub trait Parse
where
Self: std::marker::Sized,
{
fn parse(stream: TokenStream) -> Result<Self, Error>;
}
impl Parse for Type {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
let kind = if let Some(Token::BracketOpen) = stream.peek() {
stream.expect(Token::BracketOpen)?;
let inner = stream.parse::<Type>()?;
stream.expect(Token::Semi)?;
let length = if let Some(Token::DecimalValue(length)) = stream.next() {
length
} else {
return Err(stream.expected_err("array length (number)")?);
};
stream.expect(Token::BracketClose)?;
TypeKind::Array(
Box::new(inner.0),
length.parse().expect("Array length not parseable as u64!"),
)
} else if let Some(Token::Et) = stream.peek() {
stream.expect(Token::Et)?;
let mutable = if let Some(Token::MutKeyword) = stream.peek() {
stream.next();
true
} else {
false
};
let inner = stream.parse::<Type>()?;
TypeKind::Borrow(Box::new(inner.0), mutable)
} else if let Some(Token::Star) = stream.peek() {
stream.expect(Token::Star)?;
let inner = stream.parse::<Type>()?;
TypeKind::Ptr(Box::new(inner.0))
} else {
if let Some(Token::Identifier(ident)) = stream.next() {
match &*ident {
"bool" => TypeKind::Bool,
"i8" => TypeKind::I8,
"i16" => TypeKind::I16,
"i32" => TypeKind::I32,
"i64" => TypeKind::I64,
"i128" => TypeKind::I128,
"u8" => TypeKind::U8,
"u16" => TypeKind::U16,
"u32" => TypeKind::U32,
"u64" => TypeKind::U64,
"u128" => TypeKind::U128,
"f16" => TypeKind::F16,
"f32b" => TypeKind::F32B,
"f32" => TypeKind::F32,
"f64" => TypeKind::F64,
"f80" => TypeKind::F80,
"f128" => TypeKind::F128,
"f128ppc" => TypeKind::F128PPC,
"char" => TypeKind::Char,
_ => TypeKind::Custom(ident),
}
} else {
return Err(stream.expected_err("type identifier")?)?;
}
};
Ok(Type(kind, stream.get_range().unwrap()))
}
}
impl Parse for Expression {
fn parse(mut stream: TokenStream) -> Result<Expression, Error> {
let lhs = stream.parse::<PrimaryExpression>()?.0;
parse_binop_rhs(&mut stream, lhs, None)
}
}
impl Parse for UnaryOperator {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
if let Some(token) = stream.next() {
match token {
Token::Plus => Ok(UnaryOperator::Plus),
Token::Minus => Ok(UnaryOperator::Minus),
Token::Exclamation => Ok(UnaryOperator::Not),
_ => Err(stream.expected_err("unary operator")?),
}
} else {
Err(stream.expected_err("unary operator")?)
}
}
}
fn specific_float_lit(value: f64, stream: &mut TokenStream) -> Result<Expression, Error> {
use ExpressionKind as Kind;
let lit = match stream
.parse_if::<Type, _>(|t| match t.0 {
TypeKind::F16 => true,
TypeKind::F32B => true,
TypeKind::F32 => true,
TypeKind::F64 => true,
TypeKind::F128 => true,
TypeKind::F80 => true,
TypeKind::F128PPC => true,
_ => false,
})?
.0
{
TypeKind::F16 => SpecificLiteral::F16(value as f32),
TypeKind::F32 => SpecificLiteral::F32(value as f32),
TypeKind::F32B => SpecificLiteral::F32B(value as f32),
TypeKind::F64 => SpecificLiteral::F64(value as f64),
TypeKind::F128 => SpecificLiteral::F128(value as f64),
TypeKind::F80 => SpecificLiteral::F80(value as f64),
TypeKind::F128PPC => SpecificLiteral::F128PPC(value as f64),
_ => Err(stream.expected_err("float-compatible type")?)?,
};
Ok(Expression(
Kind::Literal(Literal::Specific(lit)),
stream.get_range().unwrap(),
))
}
fn specific_int_lit(value: u128, stream: &mut TokenStream) -> Result<Expression, Error> {
use ExpressionKind as Kind;
let lit = match stream
.parse_if::<Type, _>(|t| match t.0 {
TypeKind::Char => false,
TypeKind::Array(_, _) => false,
TypeKind::Custom(_) => false,
TypeKind::Borrow(_, _) => false,
TypeKind::Ptr(_) => false,
TypeKind::Bool => false,
_ => true,
})?
.0
{
TypeKind::I8 => SpecificLiteral::I8(value as i8),
TypeKind::I16 => SpecificLiteral::I16(value as i16),
TypeKind::I32 => SpecificLiteral::I32(value as i32),
TypeKind::I64 => SpecificLiteral::I64(value as i64),
TypeKind::I128 => SpecificLiteral::I128(value as i128),
TypeKind::U8 => SpecificLiteral::U8(value as u8),
TypeKind::U16 => SpecificLiteral::U16(value as u16),
TypeKind::U32 => SpecificLiteral::U32(value as u32),
TypeKind::U64 => SpecificLiteral::U64(value as u64),
TypeKind::U128 => SpecificLiteral::U128(value as u128),
TypeKind::F16 => SpecificLiteral::F16(value as f32),
TypeKind::F32 => SpecificLiteral::F32(value as f32),
TypeKind::F32B => SpecificLiteral::F32B(value as f32),
TypeKind::F64 => SpecificLiteral::F64(value as f64),
TypeKind::F128 => SpecificLiteral::F128(value as f64),
TypeKind::F80 => SpecificLiteral::F80(value as f64),
TypeKind::F128PPC => SpecificLiteral::F128PPC(value as f64),
_ => return Err(stream.expected_err("integer-compatible type")?),
};
Ok(Expression(
Kind::Literal(Literal::Specific(lit)),
stream.get_range().unwrap(),
))
}
#[derive(Debug)]
pub struct AssociatedFunctionCall(Type, FunctionCallExpression);
impl Parse for AssociatedFunctionCall {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
let ty = stream.parse()?;
stream.expect(Token::Colon)?;
stream.expect(Token::Colon)?;
Ok(AssociatedFunctionCall(ty, stream.parse()?))
}
}
fn apply_inner<T>(expr: PrimaryExpression, fun: T) -> Expression
where
T: FnOnce(PrimaryExpression) -> Expression,
{
match &expr.0 .0 {
ExpressionKind::Indexed(value_expr, index_expr) => Expression(
ExpressionKind::Indexed(
Box::new(apply_inner(PrimaryExpression(*value_expr.clone()), fun)),
index_expr.clone(),
),
expr.0 .1,
),
ExpressionKind::Accessed(value_expr, index_name) => Expression(
ExpressionKind::Accessed(
Box::new(apply_inner(PrimaryExpression(*value_expr.clone()), fun)),
index_name.clone(),
),
expr.0 .1,
),
ExpressionKind::AccessCall(value_expr, fn_call) => Expression(
ExpressionKind::AccessCall(
Box::new(apply_inner(PrimaryExpression(*value_expr.clone()), fun)),
fn_call.clone(),
),
expr.0 .1,
),
ExpressionKind::CastTo(value_expr, ty) => Expression(
ExpressionKind::CastTo(
Box::new(apply_inner(PrimaryExpression(*value_expr.clone()), fun)),
ty.clone(),
),
expr.0 .1,
),
_ => fun(expr),
}
}
#[derive(Debug)]
pub struct PrimaryExpression(Expression);
impl Parse for PrimaryExpression {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
use ExpressionKind as Kind;
let mut expr = if let Ok(exp) = stream.parse() {
Expression(Kind::FunctionCall(Box::new(exp)), stream.get_range().unwrap())
} else if let Ok(block) = stream.parse() {
Expression(Kind::BlockExpr(Box::new(block)), stream.get_range().unwrap())
} else if let Some(Token::If) = stream.peek() {
Expression(Kind::IfExpr(Box::new(stream.parse()?)), stream.get_range().unwrap())
} else if let (Some(Token::Et), Some(Token::MutKeyword)) = (stream.peek(), stream.peek2()) {
stream.next(); // Consume Et
stream.next(); // Consume mut
Expression(
Kind::Borrow(Box::new(stream.parse()?), true),
stream.get_range().unwrap(),
)
} else if let Some(Token::Et) = stream.peek() {
stream.next(); // Consume Et
Expression(
Kind::Borrow(Box::new(stream.parse()?), false),
stream.get_range().unwrap(),
)
} else if let Some(Token::Star) = stream.peek() {
stream.next(); // Consume Et
apply_inner(stream.parse()?, |e| {
Expression(Kind::Deref(Box::new(e.0)), stream.get_range().unwrap())
})
} else if let Ok(unary) = stream.parse() {
Expression(
Kind::UnaryOperation(unary, Box::new(stream.parse()?)),
stream.get_range().unwrap(),
)
} else if let Ok(assoc_function) = stream.parse::<AssociatedFunctionCall>() {
Expression(
Kind::AssociatedFunctionCall(assoc_function.0, Box::new(assoc_function.1)),
stream.get_range().unwrap(),
)
} else if let Some(token) = stream.peek() {
match &token {
Token::Identifier(v) => {
if let Ok(struct_expr) = stream.parse::<StructExpression>() {
let range = struct_expr.range.clone();
Expression(Kind::StructExpression(struct_expr), range)
} else {
stream.next(); // Consume ident
Expression(Kind::VariableName(v.clone()), stream.get_range().unwrap())
}
}
Token::BinaryValue(v) => {
stream.next(); // Consume binary
let value = u128::from_str_radix(&v, 2).expect("Value is not parseable as u128!");
if let Ok(expr) = specific_int_lit(value, &mut stream) {
expr
} else {
Expression(Kind::Literal(Literal::Integer(value)), stream.get_range().unwrap())
}
}
Token::OctalValue(v) => {
stream.next(); // Consume octal
let value = u128::from_str_radix(&v, 8).expect("Value is not parseable as u128!");
if let Ok(expr) = specific_int_lit(value, &mut stream) {
expr
} else {
Expression(Kind::Literal(Literal::Integer(value)), stream.get_range().unwrap())
}
}
Token::HexadecimalValue(v) => {
stream.next(); // Consume hexadecimal
let value = u128::from_str_radix(&v, 16).expect("Value is not parseable as u128!");
if let Ok(expr) = specific_int_lit(value, &mut stream) {
expr
} else {
Expression(Kind::Literal(Literal::Integer(value)), stream.get_range().unwrap())
}
}
Token::DecimalValue(v) => {
stream.next(); // Consume decimal
if let (Some(Token::Dot), Some(Token::DecimalValue(fractional))) = (stream.peek(), stream.peek2()) {
stream.next(); // Consume dot
stream.next(); // Consume fractional
let value = format!("{}.{}", v, fractional)
.parse()
.expect("Decimal is not parseable as f64!");
if let Ok(expr) = specific_float_lit(value, &mut stream) {
expr
} else {
Expression(Kind::Literal(Literal::Decimal(value)), stream.get_range().unwrap())
}
} else {
let value = u128::from_str_radix(&v, 10).expect("Value is not parseable as u128!");
if let Ok(expr) = specific_int_lit(value, &mut stream) {
expr
} else {
Expression(Kind::Literal(Literal::Integer(value)), stream.get_range().unwrap())
}
}
}
Token::StringLit(v) => {
stream.next(); // Consume
Expression(Kind::Literal(Literal::String(v.clone())), stream.get_range().unwrap())
}
Token::CharLit(v) => {
stream.next(); // Consume
let chars = v.as_bytes();
if chars.len() == 0 {
stream.expected_err("char to not be empty")?;
} else if chars.len() > 0 {
stream.expected_err("char to only have one char inside it")?;
}
Expression(
Kind::Literal(Literal::Char(v.chars().next().unwrap())),
stream.get_range().unwrap(),
)
}
Token::True => {
stream.next(); // Consume
Expression(Kind::Literal(Literal::Bool(true)), stream.get_range().unwrap())
}
Token::False => {
stream.next(); // Consume
Expression(Kind::Literal(Literal::Bool(false)), stream.get_range().unwrap())
}
Token::ParenOpen => {
stream.next(); // Consume
let exp = stream.parse()?;
stream.expect(Token::ParenClose)?;
exp
}
Token::BracketOpen => {
stream.next(); // Consume
if let Ok(exp) = stream.parse() {
if let Some(Token::Semi) = stream.peek() {
stream.next(); // Consume colon
let Some(Token::DecimalValue(val)) = stream.next() else {
return Err(stream.expecting_err("decimal value describing array length")?);
};
stream.expect(Token::BracketClose)?;
Expression(
Kind::ArrayShort(
Box::new(exp),
u64::from_str_radix(&val, 10)
.expect("Unable to parse array length to 64-bit decimal value"),
),
stream.get_range().unwrap(),
)
} else {
let mut expressions = Vec::new();
expressions.push(exp);
while let Some(Token::Comma) = stream.peek() {
stream.next(); // Consume comma
expressions.push(stream.parse()?);
}
stream.expect(Token::BracketClose)?;
Expression(Kind::Array(expressions), stream.get_range().unwrap())
}
} else {
stream.expect(Token::BraceClose)?;
Expression(Kind::Array(Vec::new()), stream.get_range().unwrap())
}
}
_ => Err(stream.expecting_err("expression")?)?,
}
} else {
Err(stream.expecting_err("expression")?)?
};
while let Ok(index) = stream.parse::<ValueIndex>() {
match index {
ValueIndex::Array(ArrayValueIndex(idx_expr)) => {
expr = Expression(
ExpressionKind::Indexed(Box::new(expr), Box::new(idx_expr)),
stream.get_range().unwrap(),
);
}
ValueIndex::Dot(val) => match val {
DotIndexKind::StructValueIndex(name) => {
expr = Expression(
ExpressionKind::Accessed(Box::new(expr), name),
stream.get_range().unwrap(),
);
}
DotIndexKind::FunctionCall(function_call_expression) => {
expr = Expression(
ExpressionKind::AccessCall(Box::new(expr), Box::new(function_call_expression)),
stream.get_range().unwrap(),
);
}
},
}
}
while let Ok(as_cast) = stream.parse::<AsCast>() {
expr = Expression(
ExpressionKind::CastTo(Box::new(expr), as_cast.0),
stream.get_range().unwrap(),
);
}
Ok(PrimaryExpression(expr))
}
}
#[derive(Debug)]
pub struct AsCast(Type);
impl Parse for AsCast {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
stream.expect(Token::AsKeyword)?;
Ok(AsCast(stream.parse()?))
}
}
/// This algorithm seems somewhat like magic to me. I understand it if I read
/// carefully, but it is difficult to read every single time.
///
/// Reference for how the algorithm is formed:
/// https://llvm.org/docs/tutorial/MyFirstLanguageFrontend/LangImpl02.html#binary-expression-parsing
fn parse_binop_rhs(
stream: &mut TokenStream,
mut lhs: Expression,
mut prev_operator: Option<BinaryOperator>,
) -> Result<Expression, Error> {
// Expression precedence = LHS precedence so far.
let expr_precedence = if let Some(op) = prev_operator.take() {
op.get_precedence()
} else {
0
};
while let Ok(op) =
// If next operator precedence is lower than expression precedence, we
// need to climb back up the recursion.
stream.parse_if::<BinaryOperator, _>(|b| b.get_precedence() >= expr_precedence)
{
let curr_token_prec = op.get_precedence();
let mut rhs = stream.parse::<PrimaryExpression>()?.0;
if let Ok(next_op) = stream.parse_peek::<BinaryOperator>() {
let next_prec = next_op.get_precedence();
if curr_token_prec < next_prec {
// Operator on the right of rhs has more precedence, turn
// rhs into lhs for new binop
rhs = parse_binop_rhs(stream, rhs, Some(op))?;
} else {
let _ = prev_operator.insert(next_op);
}
}
lhs = Expression(
ExpressionKind::Binop(op, Box::new(lhs), Box::new(rhs)),
stream.get_range_prev().unwrap(),
);
}
Ok(lhs)
}
impl Parse for BinaryOperator {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
Ok(match (stream.next(), stream.peek()) {
(Some(Token::Et), Some(Token::Et)) => {
stream.next();
BinaryOperator::And
}
(Some(Token::Pipe), Some(Token::Pipe)) => {
stream.next();
BinaryOperator::Or
}
(Some(Token::LessThan), Some(Token::Equals)) => {
stream.next();
BinaryOperator::LE
}
(Some(Token::GreaterThan), Some(Token::Equals)) => {
stream.next();
BinaryOperator::GE
}
(Some(Token::Equals), Some(Token::Equals)) => {
stream.next();
BinaryOperator::EQ
}
(Some(Token::Exclamation), Some(Token::Equals)) => {
stream.next();
BinaryOperator::NE
}
(Some(Token::GreaterThan), Some(Token::GreaterThan)) => {
stream.next();
BinaryOperator::BitshiftRight
}
(Some(Token::LessThan), Some(Token::LessThan)) => {
stream.next();
BinaryOperator::BitshiftLeft
}
(Some(Token::Hat), _) => BinaryOperator::Xor,
(Some(Token::Et), _) => BinaryOperator::BWAnd,
(Some(Token::Pipe), _) => BinaryOperator::BWOr,
(Some(Token::LessThan), _) => BinaryOperator::LT,
(Some(Token::GreaterThan), _) => BinaryOperator::GT,
(Some(Token::Plus), _) => BinaryOperator::Add,
(Some(Token::Minus), _) => BinaryOperator::Minus,
(Some(Token::Star), _) => BinaryOperator::Mult,
(Some(Token::Slash), _) => BinaryOperator::Div,
(Some(Token::Percent), _) => BinaryOperator::Mod,
(_, _) => Err(stream.expected_err("expected operator")?)?,
})
}
}
impl Parse for FunctionCallExpression {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
if let Some(Token::Identifier(name)) = stream.next() {
let args = stream.parse::<FunctionArgs>()?;
Ok(FunctionCallExpression(name, args.0, stream.get_range().unwrap()))
} else {
Err(stream.expected_err("identifier")?)
}
}
}
#[derive(Debug)]
pub struct FunctionArgs(Vec<Expression>);
impl Parse for FunctionArgs {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
stream.expect(Token::ParenOpen)?;
let mut params = Vec::new();
if let Ok(exp) = stream.parse() {
params.push(exp);
while stream.expect(Token::Comma).is_ok() {
params.push(stream.parse()?);
}
}
stream.expect(Token::ParenClose)?;
Ok(FunctionArgs(params))
}
}
impl Parse for IfExpression {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
stream.expect(Token::If)?;
let cond = stream.parse()?;
let then_b = stream.parse()?;
let else_b = if let Ok(_) = stream.expect(Token::Else) {
Some(stream.parse()?)
} else {
None
};
Ok(IfExpression(cond, then_b, else_b, stream.get_range().unwrap()))
}
}
impl Parse for LetStatement {
fn parse(mut stream: TokenStream) -> Result<LetStatement, Error> {
stream.expect(Token::LetKeyword)?;
let mutability = stream.expect(Token::MutKeyword).is_ok();
if let Some(Token::Identifier(variable)) = stream.next() {
let ty = if let Some(Token::Colon) = stream.peek() {
stream.next(); // Consume colon
Some(stream.parse()?)
} else {
None
};
let range = stream.get_range_prev().unwrap();
stream.expect(Token::Equals)?;
let expression = stream.parse()?;
stream.expect(Token::Semi)?;
Ok(LetStatement {
name: variable,
ty,
mutable: mutability,
value: expression,
name_range: range,
})
} else {
Err(stream.expected_err("identifier")?)
}
}
}
impl Parse for ImportStatement {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
stream.expect(Token::ImportKeyword)?;
let mut import_list = Vec::new();
if let Some(Token::Identifier(name)) = stream.next() {
import_list.push(name);
while stream.expect(Token::Colon).is_ok() && stream.expect(Token::Colon).is_ok() {
if let Some(Token::Identifier(name)) = stream.next() {
import_list.push(name);
} else {
Err(stream.expected_err("identifier")?)?
}
}
} else {
Err(stream.expected_err("identifier")?)?
}
stream.expect(Token::Semi)?;
Ok(ImportStatement(import_list, stream.get_range().unwrap()))
}
}
impl Parse for FunctionDefinition {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
let is_pub = if let Some(Token::PubKeyword) = stream.peek() {
stream.next(); // Consume pub
true
} else {
false
};
stream.expect(Token::FnKeyword)?;
Ok(FunctionDefinition(
stream.parse()?,
is_pub,
stream.parse()?,
stream.get_range().unwrap(),
))
}
}
#[derive(Debug)]
struct FunctionParam(String, Type);
impl Parse for FunctionParam {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
let Some(Token::Identifier(arg_name)) = stream.next() else {
return Err(stream.expected_err("parameter name")?);
};
stream.expect(Token::Colon)?;
Ok(FunctionParam(arg_name, stream.parse()?))
}
}
#[derive(Debug)]
pub struct SelfParam(SelfKind);
pub enum SelfParamKind {
Owned,
Borrow,
BorrowMut,
}
impl Parse for SelfParam {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
let kind = if let Some(Token::Et) = stream.peek() {
stream.next();
if let Some(Token::MutKeyword) = stream.peek() {
stream.next();
SelfParamKind::BorrowMut
} else {
SelfParamKind::Borrow
}
} else {
SelfParamKind::Owned
};
let Some(Token::Identifier(name)) = stream.next() else {
return Err(stream.expected_err("parameter name")?);
};
if name == "self" {
match kind {
SelfParamKind::BorrowMut => Ok(SelfParam(SelfKind::MutBorrow(TypeKind::Unknown))),
SelfParamKind::Borrow => Ok(SelfParam(SelfKind::Borrow(TypeKind::Unknown))),
SelfParamKind::Owned => Ok(SelfParam(SelfKind::Owned(TypeKind::Unknown))),
}
} else {
Err(stream.expected_err("self parameter")?)
}
}
}
impl Parse for FunctionSignature {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
if let Some(Token::Identifier(name)) = stream.next() {
stream.expect(Token::ParenOpen)?;
let mut params = Vec::new();
let self_kind = stream.parse::<SelfParam>().map(|s| s.0).unwrap_or(SelfKind::None);
match &self_kind {
SelfKind::None => {
if let Ok(param) = stream.parse::<FunctionParam>() {
params.push((param.0, param.1));
while let Some(Token::Comma) = stream.peek() {
stream.next();
let param = stream.parse::<FunctionParam>()?;
params.push((param.0, param.1));
}
}
}
_ => {
while let Some(Token::Comma) = stream.peek() {
stream.next();
let param = stream.parse::<FunctionParam>()?;
params.push((param.0, param.1));
}
}
}
stream.expect(Token::ParenClose)?;
let mut return_type = None;
if stream.expect(Token::Arrow).is_ok() {
return_type = Some(stream.parse()?);
}
Ok(FunctionSignature {
name,
params,
self_kind,
return_type,
range: stream.get_range().unwrap(),
})
} else {
Err(stream.expected_err("identifier")?)?
}
}
}
impl Parse for Block {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
let mut statements = Vec::new();
let mut return_stmt = None;
stream.expect(Token::BraceOpen)?;
while !matches!(stream.peek(), Some(Token::BraceClose)) {
if let Some((_, Some(e))) = return_stmt.take() {
// Special list of expressions that are simply not warned about,
// if semicolon is missing.
if !matches!(e, Expression(ExpressionKind::IfExpr(_), _)) {
// In theory could ignore the missing semicolon..
return Err(stream.expected_err("semicolon to complete statement")?);
}
statements.push(BlockLevelStatement::Expression(e));
}
let statement = stream.parse()?;
if let BlockLevelStatement::Return(r_type, e) = &statement {
match r_type {
ReturnType::Hard => {
return_stmt = Some((*r_type, e.clone()));
break; // Return has to be the last statement
// TODO: Make a mechanism that "can" parse even after this
}
ReturnType::Soft => {
return_stmt = Some((*r_type, e.clone()));
continue; // In theory possible to have lines after a soft return
}
};
}
statements.push(statement);
}
stream.expect(Token::BraceClose)?;
Ok(Block(statements, return_stmt, stream.get_range_prev().unwrap()))
}
}
impl Parse for StructExpression {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
let Some(Token::Identifier(name)) = stream.next() else {
return Err(stream.expected_err("struct identifier")?);
};
stream.expect(Token::BraceOpen)?;
let named_list = stream.parse::<NamedFieldList<Expression>>()?;
let fields = named_list.0.into_iter().map(|f| (f.0, f.1)).collect();
stream.expect(Token::BraceClose)?;
Ok(StructExpression {
name,
fields,
range: stream.get_range().unwrap(),
})
}
}
#[derive(Debug)]
pub struct NamedFieldList<T: Parse + std::fmt::Debug>(Vec<NamedField<T>>);
impl<T: Parse + std::fmt::Debug> Parse for NamedFieldList<T> {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
let mut fields = Vec::new();
while let Ok(field) = stream.parse() {
fields.push(field);
match stream.peek() {
Some(Token::Comma) => {
stream.next();
} // Consume comma
Some(Token::BraceClose) => break,
Some(_) | None => Err(stream.expecting_err("another field or closing brace")?)?,
}
}
Ok(NamedFieldList(fields))
}
}
#[derive(Debug)]
pub struct NamedField<T: Parse + std::fmt::Debug>(String, T, TokenRange);
impl<T: Parse + std::fmt::Debug> Parse for NamedField<T> {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
let Some(Token::Identifier(field_name)) = stream.next() else {
return Err(stream.expected_err("type name")?);
};
stream.expect(Token::Colon)?;
let value = stream.parse()?;
Ok(NamedField(field_name, value, stream.get_range().unwrap()))
}
}
#[derive(Debug, Clone)]
pub enum ValueIndex {
Array(ArrayValueIndex),
Dot(DotIndexKind),
}
impl Parse for ValueIndex {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
match stream.peek() {
Some(Token::BracketOpen) => Ok(ValueIndex::Array(stream.parse()?)),
Some(Token::Dot) => Ok(ValueIndex::Dot(stream.parse()?)),
_ => Err(stream.expecting_err("value or struct index")?),
}
}
}
#[derive(Debug, Clone)]
pub struct ArrayValueIndex(Expression);
impl Parse for ArrayValueIndex {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
stream.expect(Token::BracketOpen)?;
let expr = stream.parse()?;
stream.expect(Token::BracketClose)?;
Ok(ArrayValueIndex(expr))
}
}
#[derive(Debug, Clone)]
pub enum DotIndexKind {
StructValueIndex(String),
FunctionCall(FunctionCallExpression),
}
impl Parse for DotIndexKind {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
stream.expect(Token::Dot)?;
if let Some(Token::Identifier(name)) = stream.next() {
if let Ok(args) = stream.parse::<FunctionArgs>() {
Ok(Self::FunctionCall(FunctionCallExpression(
name,
args.0,
stream.get_range_prev().unwrap(),
)))
} else {
Ok(Self::StructValueIndex(name))
}
} else {
return Err(stream.expected_err("struct index (number)")?);
}
}
}
impl Parse for BlockLevelStatement {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
use BlockLevelStatement as Stmt;
Ok(match stream.peek() {
Some(Token::LetKeyword) => Stmt::Let(stream.parse()?),
Some(Token::ImportKeyword) => Stmt::Import { _i: stream.parse()? },
Some(Token::ReturnKeyword) => {
stream.next();
let exp = stream.parse().ok();
stream.expect(Token::Semi)?;
Stmt::Return(ReturnType::Hard, exp)
}
Some(Token::For) => {
let for_stmt = stream.parse::<ForStatement>()?;
Stmt::ForLoop(for_stmt.0, for_stmt.1, for_stmt.2, for_stmt.3, for_stmt.4)
}
Some(Token::While) => {
let while_stmt = stream.parse::<WhileStatement>()?;
Stmt::WhileLoop(while_stmt.0, while_stmt.1)
}
_ => {
if let Ok(SetStatement(ident, expr, range)) = stream.parse() {
Stmt::Set(ident, expr, range)
} else {
let e = stream.parse()?;
if stream.expect(Token::Semi).is_ok() {
Stmt::Expression(e)
} else {
Stmt::Return(ReturnType::Soft, Some(e))
}
}
}
})
}
}
#[derive(Debug)]
pub struct ForStatement(String, TokenRange, Expression, Expression, Block);
#[derive(Debug)]
pub struct WhileStatement(pub Expression, pub Block);
impl Parse for ForStatement {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
stream.expect(Token::For)?;
let Some(Token::Identifier(idx)) = stream.next() else {
return Err(stream.expected_err("loop counter")?);
};
let start_range = stream.get_range().unwrap();
stream.expect(Token::In)?;
let start = stream.parse()?;
stream.expect(Token::Dot)?;
stream.expect(Token::Dot)?;
let end = stream.parse()?;
Ok(ForStatement(idx, start_range, start, end, stream.parse()?))
}
}
impl Parse for WhileStatement {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
stream.expect(Token::While)?;
Ok(WhileStatement(stream.parse()?, stream.parse()?))
}
}
#[derive(Debug)]
pub struct SetStatement(Expression, Expression, TokenRange);
impl Parse for SetStatement {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
let var_ref = stream.parse()?;
stream.expect(Token::Equals)?;
let expr = stream.parse()?;
stream.expect(Token::Semi)?;
Ok(SetStatement(var_ref, expr, stream.get_range().unwrap()))
}
}
#[derive(Debug)]
pub struct StructDefinition(String, Vec<StructDefinitionField>, TokenRange);
impl Parse for StructDefinition {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
stream.expect(Token::Struct)?;
let Some(Token::Identifier(name)) = stream.next() else {
return Err(stream.expected_err("identifier")?);
};
stream.expect(Token::BraceOpen)?;
let named_fields = stream.parse::<NamedFieldList<Type>>()?;
let fields = named_fields
.0
.into_iter()
.map(|f| StructDefinitionField {
name: f.0,
ty: f.1,
range: f.2,
})
.collect();
stream.expect(Token::BraceClose)?;
Ok(StructDefinition(name, fields, stream.get_range().unwrap()))
}
}
impl Parse for TopLevelStatement {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
use TopLevelStatement as Stmt;
Ok(match stream.peek() {
Some(Token::ImportKeyword) => Stmt::Import(stream.parse()?),
Some(Token::Extern) => {
stream.next(); // Consume Extern
stream.expect(Token::FnKeyword)?;
let extern_fn = Stmt::ExternFunction(stream.parse()?);
stream.expect(Token::Semi)?;
extern_fn
}
Some(Token::FnKeyword) | Some(Token::PubKeyword) => Stmt::FunctionDefinition(stream.parse()?),
Some(Token::Struct) => {
let StructDefinition(name, fields, range) = stream.parse::<StructDefinition>()?;
Stmt::TypeDefinition(TypeDefinition {
name,
kind: TypeDefinitionKind::Struct(fields),
range,
})
}
Some(Token::Impl) => match stream.peek2() {
Some(Token::Binop) => Stmt::BinopDefinition(stream.parse()?),
Some(_) => {
let AssociatedFunctionBlock(ty, functions) = stream.parse::<AssociatedFunctionBlock>()?;
Stmt::AssociatedFunction(ty, functions)
}
_ => Err(stream.expecting_err("binop or associated function block")?)?,
},
_ => Err(stream.expecting_err("import or fn")?)?,
})
}
}
impl Parse for BinopDefinition {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
stream.expect(Token::Impl)?;
stream.expect(Token::Binop)?;
stream.expect(Token::ParenOpen)?;
let Some(Token::Identifier(lhs_name)) = stream.next() else {
return Err(stream.expected_err("lhs name")?);
};
stream.expect(Token::Colon)?;
let lhs_type = stream.parse()?;
stream.expect(Token::ParenClose)?;
let operator = stream.parse()?;
stream.expect(Token::ParenOpen)?;
let Some(Token::Identifier(rhs_name)) = stream.next() else {
return Err(stream.expected_err("rhs name")?);
};
stream.expect(Token::Colon)?;
let rhs_type = stream.parse()?;
stream.expect(Token::ParenClose)?;
let signature_range = stream.get_range().unwrap();
stream.expect(Token::Arrow)?;
Ok(BinopDefinition {
lhs: (lhs_name, lhs_type),
op: operator,
rhs: (rhs_name, rhs_type),
return_ty: stream.parse()?,
block: stream.parse()?,
signature_range,
})
}
}
#[derive(Debug)]
pub struct AssociatedFunctionBlock(Type, Vec<FunctionDefinition>);
impl Parse for AssociatedFunctionBlock {
fn parse(mut stream: TokenStream) -> Result<Self, Error> {
stream.expect(Token::Impl)?;
let ty = stream.parse::<Type>()?;
stream.expect(Token::BraceOpen)?;
let mut functions = Vec::new();
loop {
match stream.peek() {
Some(Token::FnKeyword) | Some(Token::PubKeyword) => {
let mut fun: FunctionDefinition = stream.parse()?;
fun.0.self_kind = match fun.0.self_kind {
SelfKind::Owned(_) => SelfKind::Owned(ty.0.clone()),
SelfKind::Borrow(_) => SelfKind::Borrow(ty.0.clone()),
SelfKind::MutBorrow(_) => SelfKind::MutBorrow(ty.0.clone()),
SelfKind::None => SelfKind::None,
};
functions.push(fun);
}
_ => break,
}
}
stream.expect(Token::BraceClose)?;
Ok(AssociatedFunctionBlock(ty, functions))
}
}