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#![deny(missing_debug_implementations)]
#![deny(missing_docs)]
#![deny(rust_2018_idioms)]
mod error;
mod lexer;
mod parser;
use std::{ops, str::FromStr};
pub use error::{Error, Result};
pub fn rust_grammar() -> Grammar {
let src = include_str!("../rust.ungram");
src.parse().unwrap()
}
#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct Node(usize);
#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct Token(usize);
#[derive(Default, Debug)]
pub struct Grammar {
nodes: Vec<NodeData>,
tokens: Vec<TokenData>,
}
impl FromStr for Grammar {
type Err = Error;
fn from_str(s: &str) -> Result<Self> {
let tokens = lexer::tokenize(s)?;
parser::parse(tokens)
}
}
impl Grammar {
pub fn iter(&self) -> impl Iterator<Item = Node> + '_ {
(0..self.nodes.len()).map(Node)
}
pub fn tokens(&self) -> impl Iterator<Item = Token> + '_ {
(0..self.tokens.len()).map(Token)
}
}
impl ops::Index<Node> for Grammar {
type Output = NodeData;
fn index(&self, Node(index): Node) -> &NodeData {
&self.nodes[index]
}
}
impl ops::Index<Token> for Grammar {
type Output = TokenData;
fn index(&self, Token(index): Token) -> &TokenData {
&self.tokens[index]
}
}
#[derive(Debug)]
pub struct NodeData {
pub name: String,
pub rule: Rule,
}
#[derive(Debug)]
pub struct TokenData {
pub name: String,
}
#[derive(Debug, Eq, PartialEq)]
pub enum Rule {
Labeled {
label: String,
rule: Box<Rule>,
},
Node(Node),
Token(Token),
Seq(Vec<Rule>),
Alt(Vec<Rule>),
Opt(Box<Rule>),
Rep(Box<Rule>),
}
#[test]
fn smoke() {
let grammar = include_str!("../ungrammar.ungram");
let grammar = grammar.parse::<Grammar>().unwrap();
drop(grammar)
}
#[test]
fn test_rust_grammar() {
let _ = rust_grammar();
}