Files
lang/src/v1/parser/node.rs
T
2024-10-07 19:05:33 -04:00

99 lines
2.2 KiB
Rust

use std::{
fmt::Debug,
ops::{Deref, DerefMut},
};
use super::{FileSpan, ParserError, ParserErrors, TokenCursor};
#[derive(Clone)]
pub struct Node<T> {
pub inner: Result<T, ()>,
pub span: FileSpan,
}
pub trait Parsable: Sized {
fn parse(cursor: &mut TokenCursor, errors: &mut ParserErrors) -> Result<Self, ParserError>;
}
pub trait MaybeParsable: Sized {
fn maybe_parse(
cursor: &mut TokenCursor,
errors: &mut ParserErrors,
) -> Result<Option<Self>, ParserError>;
}
impl<T: Parsable> Node<T> {
pub fn parse(cursor: &mut TokenCursor, errors: &mut ParserErrors) -> Self {
let start = cursor.next_pos();
let inner = T::parse(cursor, errors).map_err(|e| errors.add(e));
let end = cursor.prev_end();
Self {
inner,
span: start.to(end),
}
}
}
impl<T: MaybeParsable> Node<T> {
pub fn maybe_parse(cursor: &mut TokenCursor, errors: &mut ParserErrors) -> Option<Self> {
let start = cursor.next_pos();
let inner = match T::maybe_parse(cursor, errors) {
Ok(v) => Ok(v?),
Err(e) => {
errors.add(e);
Err(())
}
};
let end = cursor.prev_end();
Some(Self {
inner,
span: start.to(end),
})
}
}
impl<T> Node<T> {
pub fn new(inner: T, span: FileSpan) -> Self {
Self {
inner: Ok(inner),
span,
}
}
pub fn bx(self) -> Node<Box<T>> {
Node {
inner: self.inner.map(|v| Box::new(v)),
span: self.span,
}
}
}
impl<T> Node<Box<T>> {
pub fn unbx(self) -> Node<T> {
Node {
inner: self.inner.map(|v| *v),
span: self.span,
}
}
}
impl<T> Deref for Node<T> {
type Target = Result<T, ()>;
fn deref(&self) -> &Self::Target {
&self.inner
}
}
impl<T> DerefMut for Node<T> {
fn deref_mut(&mut self) -> &mut Self::Target {
&mut self.inner
}
}
impl<T: Debug> Debug for Node<T> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match &self.inner {
Ok(v) => v.fmt(f),
Err(_) => f.write_str("{error}"),
}
}
}