[fine] Rebuild main, it's probably broken
This commit is contained in:
parent
a9c1b04920
commit
b205ebcb4c
4 changed files with 24 additions and 892 deletions
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@ -1,9 +1,9 @@
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use fine::parser::old::Parser;
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use fine::parser::parse;
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use fine::semantics::Semantics;
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use std::env;
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use std::fs;
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pub fn process_file(file: &str) {
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println!("{file}");
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let source = match fs::read_to_string(file) {
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Ok(c) => c,
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Err(e) => {
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@ -12,20 +12,20 @@ pub fn process_file(file: &str) {
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}
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};
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let (mut tree, expr, lines) = Parser::new(&source).parse();
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if tree.errors.len() > 0 {
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for error in tree.errors {
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eprintln!("{error}");
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}
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return;
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// What am I doing here?
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let (tree, lines) = parse(&source);
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let semantics = Semantics::new(&tree, &lines);
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// This is... probably wrong, I don't know, what am I doing?
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for t in tree.trees() {
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let _ = semantics.type_of(t, false);
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}
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let _expr_type = tree.expr_type(&expr, &lines, true);
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if tree.errors.len() > 0 {
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for error in tree.errors {
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eprintln!("{error}");
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}
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return;
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// OK now there might be errors.
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let mut errors = semantics.snapshot_errors();
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errors.reverse();
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for e in errors {
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eprintln!("{file}: {}:{}: {}", e.start.0, e.start.1, e.message);
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}
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}
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@ -4,8 +4,6 @@ use crate::tokens::{Lines, Token, TokenKind, Tokens};
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use std::fmt::Write as _;
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use std::{cell::Cell, num::NonZeroU32};
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pub mod old; // Until I decide to delete it.
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pub struct SyntaxTree<'a> {
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trees: Vec<Tree<'a>>,
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root: Option<TreeRef>,
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@ -68,6 +66,10 @@ impl<'a> SyntaxTree<'a> {
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self[t].end_pos
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}
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pub fn trees(&self) -> impl Iterator<Item = TreeRef> {
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(0..self.trees.len()).map(|i| TreeRef::from_index(i))
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}
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pub fn find_tree_at(&self, pos: usize) -> Option<TreeRef> {
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let mut current = self.root?;
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let mut tree = &self[current];
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@ -1,872 +0,0 @@
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use crate::tokens::{Lines, Token, TokenKind, Tokens};
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use std::fmt;
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// TODO: An error should have:
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//
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// - a start
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// - an end
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// - a focus
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// - descriptive messages
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//
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// that will have to wait for now
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#[derive(PartialEq, Eq)]
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pub struct SyntaxError {
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pub start: (usize, usize),
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pub end: (usize, usize),
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pub message: String,
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}
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impl SyntaxError {
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pub fn new<T>(line: usize, column: usize, message: T) -> Self
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where
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T: ToString,
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{
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SyntaxError {
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start: (line, column),
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end: (line, column),
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message: message.to_string(),
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}
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}
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pub fn new_spanned<T>(start: (usize, usize), end: (usize, usize), message: T) -> Self
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where
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T: ToString,
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{
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SyntaxError {
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start,
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end,
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message: message.to_string(),
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}
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}
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}
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impl fmt::Debug for SyntaxError {
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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write!(f, "{self}")
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}
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}
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impl fmt::Display for SyntaxError {
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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write!(f, "{}:{}: {}", self.start.0, self.end.0, self.message)
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}
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}
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#[derive(Clone)]
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pub enum Literal {
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Float64(f64),
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String(String),
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Bool(bool),
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}
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#[derive(Copy, Clone)]
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pub enum UnaryOp {
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Negate,
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Not,
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}
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#[derive(Copy, Clone)]
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pub enum BinaryOp {
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Add,
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Subtract,
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Multiply,
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Divide,
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And,
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Or,
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}
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#[derive(Clone)]
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pub enum Expr<'a> {
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Literal(Literal, Token<'a>),
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Unary(UnaryOp, Token<'a>, ExprRef),
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Binary(BinaryOp, Token<'a>, ExprRef, ExprRef),
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Conditional(Token<'a>, ExprRef, ExprRef, Option<ExprRef>, Token<'a>),
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}
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#[derive(Clone)]
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pub struct ExprRef(Option<usize>);
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impl ExprRef {
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pub fn error() -> Self {
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ExprRef(None)
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}
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}
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// TODO: Eventually we will be unable to use Eq and PartialEq here, and will
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// need to do out own thing.
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#[derive(Copy, Clone)]
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pub enum Type {
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// Signals a type error. If you receive this then you know that an error
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// has already been reported; if you produce this be sure to also note
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// the error in the errors collection.
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Error,
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// Signals that the expression has a control-flow side-effect and that no
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// value will ever result from this expression. Usually this means
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// everything's fine.
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Unreachable,
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// TODO: Numeric literals should be implicitly convertable, unlike other
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// types. Maybe just "numeric literal" type?
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F64,
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String,
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Bool,
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}
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impl Type {
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pub fn is_error(&self) -> bool {
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match self {
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Type::Error => true,
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_ => false,
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}
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}
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pub fn compatible_with(&self, other: &Type) -> bool {
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// TODO: This is wrong; we because of numeric literals etc.
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match (self, other) {
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(Type::F64, Type::F64) => true,
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(Type::String, Type::String) => true,
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(Type::Bool, Type::Bool) => true,
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(Type::Unreachable, Type::Unreachable) => true,
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// Avoid introducing more errors
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(Type::Error, _) => true,
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(_, Type::Error) => true,
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(_, _) => false,
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}
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}
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}
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impl std::fmt::Debug for Type {
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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write!(f, "{self}")
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}
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}
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impl std::fmt::Display for Type {
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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use Type::*;
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match self {
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Error => write!(f, "<< INTERNAL ERROR >>"),
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Unreachable => write!(f, "<< UNREACHABLE >>"),
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F64 => write!(f, "f64"),
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String => write!(f, "string"),
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Bool => write!(f, "bool"),
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}
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}
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}
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pub struct SyntaxTree<'a> {
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pub errors: Vec<SyntaxError>,
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expressions: Vec<Expr<'a>>,
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}
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impl<'a> SyntaxTree<'a> {
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pub fn new() -> Self {
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SyntaxTree {
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errors: Vec::new(),
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expressions: Vec::new(),
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}
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}
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pub fn add_error(&mut self, error: SyntaxError) {
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self.errors.push(error);
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}
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pub fn add_expr(&mut self, expr: Expr<'a>) -> ExprRef {
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let index = self.expressions.len();
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self.expressions.push(expr);
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ExprRef(Some(index))
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}
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pub fn dump_expr(&self, expr: &ExprRef) -> String {
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match expr.0 {
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Some(idx) => {
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let expr = &self.expressions[idx];
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match expr {
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Expr::Literal(_, tok) => tok.to_string(),
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Expr::Unary(_, tok, e) => {
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format!("({tok} {})", self.dump_expr(e))
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}
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Expr::Binary(_, tok, l, r) => {
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format!("({tok} {} {})", self.dump_expr(l), self.dump_expr(r))
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}
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Expr::Conditional(tok, cond, t, e, _) => {
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if let Some(e) = e {
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format!(
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"({tok} {} {} {})",
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self.dump_expr(cond),
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self.dump_expr(t),
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self.dump_expr(e)
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)
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} else {
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format!("({tok} {} {})", self.dump_expr(cond), self.dump_expr(t))
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}
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}
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}
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}
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None => "<|EOF|>".to_string(),
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}
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}
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pub fn expr_span(&self, expr: &ExprRef) -> Option<(Token<'a>, Token<'a>)> {
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let expr = match expr.0 {
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Some(idx) => &self.expressions[idx],
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None => return None,
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};
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match expr {
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Expr::Literal(_, tok) => Some((tok.clone(), tok.clone())),
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Expr::Unary(_, tok, arg) => {
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let arg = self.expr_span(arg);
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match arg {
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None => None,
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Some((_, end)) => Some((tok.clone(), end)),
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}
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}
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Expr::Binary(_, _, left, right) => {
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let left = self.expr_span(left);
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let right = self.expr_span(right);
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match (left, right) {
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(None, _) => None,
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(_, None) => None,
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(Some((start, _)), Some((_, end))) => Some((start, end)),
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}
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}
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Expr::Conditional(head, _, _, _, tail) => Some((head.clone(), tail.clone())),
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}
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}
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pub fn expr_type(&mut self, expr: &ExprRef, lines: &Lines, value_required: bool) -> Type {
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// TODO: Cache and work on demand? Or is this just fine?
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let exr = expr.clone();
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let expr = match expr.0 {
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Some(idx) => &self.expressions[idx],
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None => return Type::Error,
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};
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match expr {
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Expr::Literal(lit, _) => match lit {
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Literal::Float64(_) => Type::F64,
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Literal::String(_) => Type::String,
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Literal::Bool(_) => Type::Bool,
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},
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// Figure out the main thing. Check for a... trait?
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Expr::Unary(op, tok, arg) => {
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let op = op.clone();
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let arg = arg.clone();
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let tok = tok.clone();
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let arg_type = self.expr_type(&arg, lines, true);
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match (op, arg_type) {
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(UnaryOp::Negate, Type::F64) => Type::F64,
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(UnaryOp::Not, Type::Bool) => Type::Bool,
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// This is dumb and should be punished, probably.
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(_, Type::Unreachable) => {
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let (line, col) = lines.position(tok.start);
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self.errors.push(SyntaxError::new(line, col, format!("cannot apply a unary operator to something that doesn't yield a value")));
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Type::Error
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}
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// Propagate existing errors without additional complaint.
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(_, Type::Error) => Type::Error,
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// Missed the whole table, must be an error.
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(_, arg_type) => {
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let (line, col) = lines.position(tok.start);
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self.errors.push(SyntaxError::new(line, col, format!("cannot apply unary operator '{tok}' to expression of type '{arg_type}'")));
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Type::Error
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}
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}
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}
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Expr::Binary(op, tok, left, right) => {
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let op = op.clone();
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let tok = tok.clone();
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let left = left.clone();
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let right = right.clone();
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let left_type = self.expr_type(&left, lines, true);
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let right_type = self.expr_type(&right, lines, true);
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match (op, left_type, right_type) {
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(
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BinaryOp::Add | BinaryOp::Subtract | BinaryOp::Multiply | BinaryOp::Divide,
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Type::F64,
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Type::F64,
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) => Type::F64,
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(BinaryOp::Add, Type::String, Type::String) => Type::String,
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(BinaryOp::And | BinaryOp::Or, Type::Bool, Type::Bool) => Type::Bool,
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// This is dumb and should be punished, probably.
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(_, _, Type::Unreachable) => {
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let (line, col) = lines.position(tok.start);
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self.errors.push(SyntaxError::new(
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line,
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col,
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format!(
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"cannot apply '{tok}' to an argument that doesn't yield a value (on the right)"
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),
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));
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Type::Error
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}
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(_, Type::Unreachable, _) => {
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let (line, col) = lines.position(tok.start);
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self.errors.push(SyntaxError::new(
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line,
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col,
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format!(
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"cannot apply '{tok}' to an argument that doesn't yield a value (on the left)"
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),
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));
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Type::Error
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}
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// Propagate existing errors without additional complaint.
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(_, Type::Error, _) => Type::Error,
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(_, _, Type::Error) => Type::Error,
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// Missed the whole table, it must be an error.
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(_, left_type, right_type) => {
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let (line, col) = lines.position(tok.start);
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self.errors.push(SyntaxError::new(line, col, format!("cannot apply binary operator '{tok}' to expressions of type '{left_type}' (on the left) and '{right_type}' (on the right)")));
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Type::Error
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}
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}
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}
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Expr::Conditional(_, cond, then_exp, else_exp, _) => {
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let cond = cond.clone();
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let then_exp = then_exp.clone();
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let else_exp = else_exp.clone();
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let cond_type = self.expr_type(&cond, lines, true);
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let then_type = self.expr_type(&then_exp, lines, value_required);
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let else_type = else_exp.map(|e| self.expr_type(&e, lines, value_required));
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if !cond_type.compatible_with(&Type::Bool) {
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if !cond_type.is_error() {
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let span = self
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.expr_span(&cond)
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.expect("If the expression has a type it must have a span");
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let start = lines.position(span.0.start);
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let end = lines.position(span.1.start);
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self.errors.push(SyntaxError::new_spanned(
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start,
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end,
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"the condition of an `if` expression must be a boolean",
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));
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}
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return Type::Error;
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}
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match (then_type, else_type) {
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(Type::Error, _) => Type::Error,
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(_, Some(Type::Error)) => Type::Error,
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|
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// It's an error to have a missing else branch if the value is required
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(_, None) if value_required => {
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let span = self
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.expr_span(&exr)
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.expect("How did I get this far with a broken parse?");
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let start = lines.position(span.0.start);
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let end = lines.position(span.1.start);
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self.errors.push(SyntaxError::new_spanned(
|
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start,
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end,
|
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"this `if` expression must have both a `then` clause and an `else` clause, so it can produce a value",
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));
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Type::Error
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}
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// If the value is required then the branches must be
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// compatible, and the type of the expression is the type
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// of the `then` branch.
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(then_type, Some(else_type)) if value_required => {
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if !then_type.compatible_with(&else_type) {
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let span = self
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.expr_span(&exr)
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.expect("How did I get this far with a broken parse?");
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let start = lines.position(span.0.start);
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let end = lines.position(span.1.start);
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self.errors.push(SyntaxError::new_spanned(
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start,
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end,
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format!("the type of the `then` branch ({then_type}) must match the type of the `else` branch ({else_type})"),
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));
|
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Type::Error
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} else {
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then_type
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}
|
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}
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|
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// The value must not be required, just mark this as unreachable.
|
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(_, _) => {
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assert!(!value_required);
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Type::Unreachable
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}
|
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}
|
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}
|
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}
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}
|
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}
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// BINDING POWERS. When parsing expressions we only accept expressions that
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// meet a minimum binding power. (This is like "precedence" but I just super
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// don't like that terminology.)
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const ASSIGNMENT_POWER: u8 = 0; // =
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const OR_POWER: u8 = 1; // or
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const AND_POWER: u8 = 2; // and
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const EQUALITY_POWER: u8 = 3; // == !=
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const COMPARISON_POWER: u8 = 4; // < > <= >=
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const TERM_POWER: u8 = 5; // + -
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const FACTOR_POWER: u8 = 6; // * /
|
||||
const UNARY_POWER: u8 = 7; // ! -
|
||||
|
||||
// const CALL_POWER: u8 = 8; // . ()
|
||||
// const PRIMARY_POWER: u8 = 9;
|
||||
|
||||
fn token_power<'a>(token: TokenKind) -> Option<u8> {
|
||||
match token {
|
||||
TokenKind::Equal => Some(ASSIGNMENT_POWER),
|
||||
TokenKind::Or => Some(OR_POWER),
|
||||
TokenKind::And => Some(AND_POWER),
|
||||
TokenKind::EqualEqual | TokenKind::BangEqual => Some(EQUALITY_POWER),
|
||||
TokenKind::Less | TokenKind::Greater | TokenKind::GreaterEqual | TokenKind::LessEqual => {
|
||||
Some(COMPARISON_POWER)
|
||||
}
|
||||
TokenKind::Plus | TokenKind::Minus => Some(TERM_POWER),
|
||||
TokenKind::Star | TokenKind::Slash => Some(FACTOR_POWER),
|
||||
_ => None,
|
||||
}
|
||||
}
|
||||
|
||||
pub struct Parser<'a> {
|
||||
tokens: Tokens<'a>,
|
||||
tree: SyntaxTree<'a>,
|
||||
current: Token<'a>,
|
||||
previous: Token<'a>,
|
||||
|
||||
panic_mode: bool,
|
||||
}
|
||||
|
||||
impl<'a> Parser<'a> {
|
||||
pub fn new(source: &'a str) -> Self {
|
||||
let mut parser = Parser {
|
||||
tokens: Tokens::new(source),
|
||||
tree: SyntaxTree::new(),
|
||||
current: Token::new(TokenKind::EOF, 0, ""),
|
||||
previous: Token::new(TokenKind::EOF, 0, ""),
|
||||
panic_mode: false,
|
||||
};
|
||||
parser.advance();
|
||||
parser
|
||||
}
|
||||
|
||||
pub fn parse(mut self) -> (SyntaxTree<'a>, ExprRef, Lines) {
|
||||
let expr = self.expression();
|
||||
self.consume(TokenKind::EOF, "expected end of expression");
|
||||
(self.tree, expr, self.tokens.lines())
|
||||
}
|
||||
|
||||
fn expression(&mut self) -> ExprRef {
|
||||
self.expression_with_power(0)
|
||||
}
|
||||
|
||||
fn expression_with_power(&mut self, minimum_power: u8) -> ExprRef {
|
||||
self.trace("expression with power");
|
||||
self.advance();
|
||||
let mut expr = self.prefix_expression();
|
||||
loop {
|
||||
let power = match token_power(self.current.kind) {
|
||||
Some(p) => p,
|
||||
None => break, // EOF, end of expression?
|
||||
};
|
||||
|
||||
if power < minimum_power {
|
||||
break;
|
||||
}
|
||||
|
||||
self.advance();
|
||||
expr = self.infix_expression(power, expr);
|
||||
}
|
||||
expr
|
||||
}
|
||||
|
||||
fn prefix_expression(&mut self) -> ExprRef {
|
||||
self.trace("prefix");
|
||||
let token = &self.previous;
|
||||
match token.kind {
|
||||
TokenKind::Bang => self.unary(),
|
||||
TokenKind::LeftParen => self.grouping(),
|
||||
TokenKind::Number => self.number(),
|
||||
TokenKind::Minus => self.unary(),
|
||||
TokenKind::String => self.string(),
|
||||
|
||||
TokenKind::True => self
|
||||
.tree
|
||||
.add_expr(Expr::Literal(Literal::Bool(true), token.clone())),
|
||||
TokenKind::False => self
|
||||
.tree
|
||||
.add_expr(Expr::Literal(Literal::Bool(false), token.clone())),
|
||||
|
||||
TokenKind::If => self.conditional(),
|
||||
|
||||
_ => {
|
||||
self.error("expected an expression");
|
||||
ExprRef::error()
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
fn infix_expression(&mut self, power: u8, left: ExprRef) -> ExprRef {
|
||||
self.trace("infix");
|
||||
match self.previous.kind {
|
||||
TokenKind::Plus
|
||||
| TokenKind::Minus
|
||||
| TokenKind::Star
|
||||
| TokenKind::Slash
|
||||
| TokenKind::And
|
||||
| TokenKind::Or => self.binary(power, left),
|
||||
_ => panic!("Unknown infix operator, dispatch error?"),
|
||||
}
|
||||
}
|
||||
|
||||
fn number(&mut self) -> ExprRef {
|
||||
let token = &self.previous;
|
||||
// What kind is it? For now let's just ... make it good.
|
||||
|
||||
let literal = match token.as_str().parse::<f64>() {
|
||||
Ok(v) => Literal::Float64(v),
|
||||
Err(e) => {
|
||||
self.error(format!("invalid f64: {e}"));
|
||||
return ExprRef::error();
|
||||
}
|
||||
};
|
||||
|
||||
self.tree.add_expr(Expr::Literal(literal, token.clone()))
|
||||
}
|
||||
|
||||
fn string(&mut self) -> ExprRef {
|
||||
let token = &self.previous;
|
||||
|
||||
let mut result = String::new();
|
||||
let mut input = token.as_str().chars();
|
||||
|
||||
assert!(input.next().is_some()); // Delimiter
|
||||
while let Some(ch) = input.next() {
|
||||
match ch {
|
||||
'\\' => match input.next().unwrap() {
|
||||
'n' => result.push('\n'),
|
||||
'r' => result.push('\r'),
|
||||
't' => result.push('\t'),
|
||||
ch => result.push(ch),
|
||||
},
|
||||
_ => result.push(ch),
|
||||
}
|
||||
}
|
||||
result.pop(); // We pushed the other delimiter on, whoops.
|
||||
|
||||
let literal = Literal::String(result);
|
||||
self.tree.add_expr(Expr::Literal(literal, token.clone()))
|
||||
}
|
||||
|
||||
fn grouping(&mut self) -> ExprRef {
|
||||
let result = self.expression();
|
||||
self.consume(TokenKind::RightParen, "expected ')' after an expression");
|
||||
result
|
||||
}
|
||||
|
||||
fn conditional(&mut self) -> ExprRef {
|
||||
let token = self.previous.clone();
|
||||
let condition_expr = self.expression();
|
||||
self.consume(TokenKind::LeftBrace, "expected '{' to start an 'if' block");
|
||||
let then_expr = self.expression();
|
||||
self.consume(TokenKind::RightBrace, "expected '}' to end an 'if' block");
|
||||
let else_expr = if self.current.kind == TokenKind::Else {
|
||||
self.advance();
|
||||
if self.current.kind == TokenKind::If {
|
||||
self.advance();
|
||||
Some(self.conditional())
|
||||
} else {
|
||||
self.consume(
|
||||
TokenKind::LeftBrace,
|
||||
"expected '{' to start an 'else' block",
|
||||
);
|
||||
let else_expr = self.expression();
|
||||
self.consume(TokenKind::RightBrace, "Expected '}' to end an 'else' block");
|
||||
Some(else_expr)
|
||||
}
|
||||
} else {
|
||||
None
|
||||
};
|
||||
let tail = self.previous.clone();
|
||||
self.tree.add_expr(Expr::Conditional(
|
||||
token,
|
||||
condition_expr,
|
||||
then_expr,
|
||||
else_expr,
|
||||
tail,
|
||||
))
|
||||
}
|
||||
|
||||
fn unary(&mut self) -> ExprRef {
|
||||
let token = self.previous.clone();
|
||||
let kind = token.kind;
|
||||
let expr = self.expression_with_power(UNARY_POWER);
|
||||
let op = match kind {
|
||||
TokenKind::Minus => UnaryOp::Negate,
|
||||
TokenKind::Bang => UnaryOp::Not,
|
||||
_ => panic!("unsuitable unary: {:?}: no op", kind),
|
||||
};
|
||||
|
||||
self.tree.add_expr(Expr::Unary(op, token, expr))
|
||||
}
|
||||
|
||||
fn binary(&mut self, power: u8, left: ExprRef) -> ExprRef {
|
||||
let token = self.previous.clone();
|
||||
let op = match token.kind {
|
||||
TokenKind::Plus => BinaryOp::Add,
|
||||
TokenKind::Minus => BinaryOp::Subtract,
|
||||
TokenKind::Star => BinaryOp::Multiply,
|
||||
TokenKind::Slash => BinaryOp::Divide,
|
||||
TokenKind::And => BinaryOp::And,
|
||||
TokenKind::Or => BinaryOp::Or,
|
||||
_ => panic!("unsuitable binary: {:?}: no op", self.previous),
|
||||
};
|
||||
let right = self.expression_with_power(power + 1);
|
||||
self.tree.add_expr(Expr::Binary(op, token, left, right))
|
||||
}
|
||||
|
||||
fn advance(&mut self) {
|
||||
self.previous = self.current.clone();
|
||||
self.current = self.tokens.next();
|
||||
while self.current.kind == TokenKind::Error
|
||||
|| self.current.kind == TokenKind::Whitespace
|
||||
|| self.current.kind == TokenKind::Comment
|
||||
{
|
||||
if self.current.kind == TokenKind::Error {
|
||||
self.error_at_current(self.current.to_string());
|
||||
}
|
||||
self.current = self.tokens.next();
|
||||
}
|
||||
}
|
||||
|
||||
fn consume(&mut self, kind: TokenKind, error: &str) {
|
||||
if self.current.kind == kind {
|
||||
self.advance();
|
||||
} else {
|
||||
self.error_at_current(error);
|
||||
}
|
||||
}
|
||||
|
||||
fn error<T>(&mut self, message: T)
|
||||
where
|
||||
T: Into<String>,
|
||||
{
|
||||
self.error_at(self.previous.clone(), message)
|
||||
}
|
||||
|
||||
fn error_at_current<T>(&mut self, message: T)
|
||||
where
|
||||
T: Into<String>,
|
||||
{
|
||||
self.error_at(self.current.clone(), message)
|
||||
}
|
||||
|
||||
fn error_at<T>(&mut self, token: Token<'a>, message: T)
|
||||
where
|
||||
T: Into<String>,
|
||||
{
|
||||
if self.panic_mode {
|
||||
return;
|
||||
}
|
||||
self.panic_mode = true;
|
||||
|
||||
let message: String = message.into();
|
||||
let (line, column) = self.tokens.token_position(&token);
|
||||
let mut final_message = "Error ".to_string();
|
||||
|
||||
if token.kind == TokenKind::EOF {
|
||||
final_message.push_str("at end")
|
||||
} else if token.kind != TokenKind::Error {
|
||||
final_message.push_str("at '");
|
||||
final_message.push_str(token.as_str());
|
||||
final_message.push_str("'");
|
||||
}
|
||||
final_message.push_str(": ");
|
||||
final_message.push_str(&message);
|
||||
|
||||
self.tree
|
||||
.add_error(SyntaxError::new(line, column, final_message));
|
||||
}
|
||||
|
||||
fn trace(&self, _msg: &str) {
|
||||
// let cpos = self.tokens.token_position(&self.current);
|
||||
// let ppos = self.tokens.token_position(&self.previous);
|
||||
|
||||
// eprintln!(
|
||||
// "[{}:{}:{}] [{}:{}:{}]: {msg}",
|
||||
// ppos.0,
|
||||
// ppos.1,
|
||||
// self.previous
|
||||
// .as_ref()
|
||||
// .map(|t| t.as_str())
|
||||
// .unwrap_or("<eof>"),
|
||||
// cpos.0,
|
||||
// cpos.1,
|
||||
// self.current.as_ref().map(|t| t.as_str()).unwrap_or("<eof>")
|
||||
// );
|
||||
}
|
||||
}
|
||||
|
||||
#[cfg(test)]
|
||||
mod tests {
|
||||
use super::*;
|
||||
use pretty_assertions::assert_eq;
|
||||
|
||||
fn test_successful_expression_parse(source: &str, expected: &str, expected_type: Type) {
|
||||
let (mut tree, expr, lines) = Parser::new(source).parse();
|
||||
assert_eq!(
|
||||
Vec::<SyntaxError>::new(),
|
||||
tree.errors,
|
||||
"Expected successful parse"
|
||||
);
|
||||
assert_eq!(
|
||||
expected,
|
||||
tree.dump_expr(&expr),
|
||||
"The parse structure of the expressions did not match"
|
||||
);
|
||||
|
||||
// TODO: 'assert_eq' is probably wrong here
|
||||
let expr_type = tree.expr_type(&expr, &lines, true);
|
||||
assert!(
|
||||
expected_type.compatible_with(&expr_type),
|
||||
"The type of the expression did not match. expected: {expected_type}, actual: {expr_type}"
|
||||
);
|
||||
}
|
||||
|
||||
macro_rules! test_expr {
|
||||
($name:ident, $input:expr, $expected:expr, $type:expr) => {
|
||||
#[test]
|
||||
fn $name() {
|
||||
test_successful_expression_parse($input, $expected, $type);
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
test_expr!(number_expr, "12", "12", Type::F64);
|
||||
test_expr!(add_expr, "1 + 2", "(+ 1 2)", Type::F64);
|
||||
test_expr!(
|
||||
prec_expr,
|
||||
"1 + 2 * 3 - 7 * 7",
|
||||
"(- (+ 1 (* 2 3)) (* 7 7))",
|
||||
Type::F64
|
||||
);
|
||||
test_expr!(unary, "-((23)) * 5", "(* (- 23) 5)", Type::F64);
|
||||
test_expr!(
|
||||
strings,
|
||||
r#" "Hello " + 'world!' "#,
|
||||
r#"(+ "Hello " 'world!')"#,
|
||||
Type::String
|
||||
);
|
||||
|
||||
test_expr!(
|
||||
booleans,
|
||||
"true and false or false and !true",
|
||||
"(or (and true false) (and false (! true)))",
|
||||
Type::Bool
|
||||
);
|
||||
|
||||
test_expr!(
|
||||
if_expression,
|
||||
"if true { 23 } else { 45 }",
|
||||
"(if true 23 45)",
|
||||
Type::F64
|
||||
);
|
||||
// test_expr!(
|
||||
// if_with_return,
|
||||
// "if true { 23 } else { return 'nothing' }",
|
||||
// "",
|
||||
// Type::F64
|
||||
// );
|
||||
|
||||
// ========================================================================
|
||||
// Type Error Tests
|
||||
// ========================================================================
|
||||
|
||||
fn test_type_error_expression(source: &str, expected_errors: Vec<&str>) {
|
||||
let (mut tree, expr, lines) = Parser::new(source).parse();
|
||||
assert_eq!(
|
||||
Vec::<SyntaxError>::new(),
|
||||
tree.errors,
|
||||
"Expected successful parse"
|
||||
);
|
||||
|
||||
let expr_type = tree.expr_type(&expr, &lines, true);
|
||||
assert!(expr_type.is_error());
|
||||
|
||||
let actual_errors = tree
|
||||
.errors
|
||||
.iter()
|
||||
.map(|e| e.message.as_str())
|
||||
.collect::<Vec<_>>();
|
||||
assert_eq!(expected_errors, actual_errors);
|
||||
}
|
||||
|
||||
macro_rules! test_type_error_expr {
|
||||
($name:ident, $input:expr, $($s:expr),+) => {
|
||||
#[test]
|
||||
fn $name() {
|
||||
let expected_errors: Vec<&str> = (vec![$($s),*]);
|
||||
test_type_error_expression($input, expected_errors);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
test_type_error_expr!(
|
||||
negate_string,
|
||||
"-('what?')",
|
||||
"cannot apply unary operator '-' to expression of type 'string'"
|
||||
);
|
||||
|
||||
test_type_error_expr!(
|
||||
add_string_number,
|
||||
"'what?' + 5",
|
||||
"cannot apply binary operator '+' to expressions of type 'string' (on the left) and 'f64' (on the right)"
|
||||
);
|
||||
|
||||
test_type_error_expr!(
|
||||
add_number_string,
|
||||
"5 + 'what?'",
|
||||
"cannot apply binary operator '+' to expressions of type 'f64' (on the left) and 'string' (on the right)"
|
||||
);
|
||||
|
||||
test_type_error_expr!(
|
||||
errors_propagate_do_not_duplicate,
|
||||
"!'hello' / 27 * -('what?') + 23",
|
||||
"cannot apply unary operator '!' to expression of type 'string'",
|
||||
"cannot apply unary operator '-' to expression of type 'string'"
|
||||
);
|
||||
|
||||
test_type_error_expr!(
|
||||
if_not_bool,
|
||||
"if 23 { 1 } else { 2 }",
|
||||
"the condition of an `if` expression must be a boolean"
|
||||
);
|
||||
|
||||
test_type_error_expr!(
|
||||
if_arm_mismatch,
|
||||
"if true { 1 } else { '1' }",
|
||||
"the type of the `then` branch (f64) must match the type of the `else` branch (string)"
|
||||
);
|
||||
|
||||
test_type_error_expr!(
|
||||
if_no_else,
|
||||
"if true { 1 }",
|
||||
"this `if` expression must have both a `then` clause and an `else` clause, so it can produce a value"
|
||||
);
|
||||
}
|
||||
|
|
@ -126,7 +126,7 @@ pub struct Semantics<'a> {
|
|||
syntax_tree: &'a SyntaxTree<'a>,
|
||||
lines: &'a Lines,
|
||||
errors: RefCell<Vec<Error>>,
|
||||
types: RefCell<HashMap<TreeRef, Type>>,
|
||||
types: RefCell<HashMap<(TreeRef, bool), Type>>,
|
||||
}
|
||||
|
||||
impl<'a> Semantics<'a> {
|
||||
|
|
@ -210,7 +210,7 @@ impl<'a> Semantics<'a> {
|
|||
}
|
||||
|
||||
pub fn type_of(&self, t: TreeRef, value_required: bool) -> Option<Type> {
|
||||
if let Some(existing) = self.types.borrow().get(&t) {
|
||||
if let Some(existing) = self.types.borrow().get(&(t, value_required)) {
|
||||
return Some(existing.clone());
|
||||
}
|
||||
|
||||
|
|
@ -239,7 +239,9 @@ impl<'a> Semantics<'a> {
|
|||
// NOTE: These return `None` if they encounter some problem.
|
||||
let result = result.unwrap_or(Type::Error);
|
||||
|
||||
self.types.borrow_mut().insert(t, result.clone());
|
||||
self.types
|
||||
.borrow_mut()
|
||||
.insert((t, value_required), result.clone());
|
||||
Some(result)
|
||||
}
|
||||
|
||||
|
|
@ -509,6 +511,6 @@ impl<'a> Semantics<'a> {
|
|||
|
||||
fn type_of_identifier(&self, tree: &Tree) -> Option<Type> {
|
||||
assert_eq!(tree.kind, TreeKind::Identifier);
|
||||
todo!()
|
||||
Some(Type::Error)
|
||||
}
|
||||
}
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue