pawarser(setup): basic parser stuff and types around it. also, a builder.

This commit is contained in:
Schrottkatze 2024-10-13 16:44:59 +02:00
parent a3ab844ba7
commit ec2ff5778b
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@ -1,9 +1,15 @@
#![feature(iter_collect_into)] #![feature(iter_collect_into)]
pub mod parser { pub mod parser {
use std::cell::Cell;
use enumset::{EnumSet, EnumSetType};
use self::{error::SyntaxError, event::Event, input::Input};
pub mod input { pub mod input {
use enumset::{EnumSet, EnumSetType}; use enumset::{EnumSet, EnumSetType};
struct Input<'src, 'toks, SyntaxKind: EnumSetType + Into<rowan::SyntaxKind>> { pub struct Input<'src, 'toks, SyntaxKind: EnumSetType + Into<rowan::SyntaxKind>> {
raw: &'toks Vec<(SyntaxKind, &'src str)>, raw: &'toks Vec<(SyntaxKind, &'src str)>,
// enumset of meaningless tokens // enumset of meaningless tokens
semantically_meaningless: EnumSet<SyntaxKind>, semantically_meaningless: EnumSet<SyntaxKind>,
@ -36,4 +42,125 @@ pub mod parser {
} }
} }
} }
mod event {
use enumset::EnumSetType;
use super::error::SyntaxError;
pub enum Event<SyntaxKind: EnumSetType + Into<rowan::SyntaxKind>, SyntaxErr: SyntaxError> {
Start {
kind: NodeKind<SyntaxKind, SyntaxErr>,
forward_parent: Option<usize>,
},
Finish,
Eat {
count: usize,
},
}
impl<SyntaxKind: EnumSetType + Into<rowan::SyntaxKind>, SyntaxErr: SyntaxError>
Event<SyntaxKind, SyntaxErr>
{
pub fn tombstone() -> Self {
Self::Start {
kind: NodeKind::Tombstone,
forward_parent: None,
}
}
}
pub enum NodeKind<SyntaxKind: EnumSetType + Into<rowan::SyntaxKind>, SyntaxErr: SyntaxError> {
Tombstone,
Syntax(SyntaxKind),
Error(SyntaxErr),
}
impl<SyntaxKind: EnumSetType + Into<rowan::SyntaxKind>, SyntaxErr: SyntaxError>
NodeKind<SyntaxKind, SyntaxErr>
{
pub fn is_tombstone(&self) -> bool {
matches!(self, Self::Tombstone)
}
pub fn is_syntax(&self) -> bool {
matches!(self, Self::Syntax(_))
}
pub fn is_error(&self) -> bool {
matches!(self, Self::Error(_))
}
}
}
mod error {
/// A marker trait... for now!
// TODO: constrain that conversion to `NodeKind::Error` is enforced to be possible
pub trait SyntaxError {}
}
pub struct Parser<
'src,
'toks,
SyntaxKind: EnumSetType + Into<rowan::SyntaxKind>,
SyntaxErr: SyntaxError,
> {
input: Input<'src, 'toks, SyntaxKind>,
pos: usize,
events: Vec<Event<SyntaxKind, SyntaxErr>>,
step_limit: u32,
steps: Cell<u32>,
}
pub struct ParserBuilder<
'src,
'toks,
SyntaxKind: EnumSetType + Into<rowan::SyntaxKind>,
// SyntaxErr: SyntaxError,
> {
raw_toks: &'toks Vec<(SyntaxKind, &'src str)>,
meaningless_token_kinds: EnumSet<SyntaxKind>,
step_limit: u32,
}
impl<'src, 'toks, SyntaxKind: EnumSetType + Into<rowan::SyntaxKind>>
ParserBuilder<'src, 'toks, SyntaxKind>
{
pub fn new(raw_toks: &'toks Vec<(SyntaxKind, &'src str)>) -> Self {
Self {
raw_toks,
meaningless_token_kinds: EnumSet::new(),
step_limit: 4096,
}
}
/// Sets the parser step limit.
/// Defaults to 4096
pub fn step_limit(mut self, new: u32) -> Self {
self.step_limit = new;
self
}
pub fn add_meaningless(mut self, kind: SyntaxKind) -> Self {
self.meaningless_token_kinds.insert(kind);
self
}
pub fn add_meaningless_many(mut self, kind: Vec<SyntaxKind>) -> Self {
self.meaningless_token_kinds
.insert_all(kind.into_iter().collect());
self
}
pub fn build<SyntaxErr: SyntaxError>(self) -> Parser<'src, 'toks, SyntaxKind, SyntaxErr> {
let Self {
raw_toks,
meaningless_token_kinds,
step_limit,
} = self;
Parser {
input: Input::new(raw_toks, Some(meaningless_token_kinds)),
pos: 0,
events: Vec::new(),
step_limit,
steps: Cell::new(0),
}
}
}
} }