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#[macro_use]
extern crate pest_derive;
extern crate from_pest;
#[macro_use]
extern crate pest_ast;
extern crate pest;
mod parser {
#[derive(Parser)]
#[grammar = "grammar.pest"]
pub struct Parser;
}
mod ast {
use super::parser::Rule;
use pest::Span;
fn span_into_str(span: Span) -> &str {
span.as_str()
}
#[derive(Debug, FromPest)]
#[pest_ast(rule(Rule::program))]
pub struct Program {
pub statements: Vec<Statement>,
eoi: EOI,
}
#[derive(Debug, FromPest)]
#[pest_ast(rule(Rule::statement))]
pub enum Statement {
Definition(Definition),
Expression(Expression),
}
#[derive(Debug, FromPest)]
#[pest_ast(rule(Rule::definition))]
pub struct Definition {
pub symbols: Vec<Symbol>,
pub expression: Expression,
}
#[derive(Debug, FromPest)]
#[pest_ast(rule(Rule::expression))]
pub struct Expression {
pub leaves: Vec<Leaf>,
}
#[derive(Debug, FromPest)]
#[pest_ast(rule(Rule::leaf))]
pub enum Leaf {
Symbol(Symbol),
IntegerLiteral(IntegerLiteral),
}
#[derive(Debug, FromPest)]
#[pest_ast(rule(Rule::integer_literal))]
pub struct IntegerLiteral {
#[pest_ast(outer(with(span_into_str), with(str::parse::<i64>), with(Result::unwrap)))]
pub value: i64,
}
#[derive(Debug, FromPest)]
#[pest_ast(rule(Rule::symbol))]
pub struct Symbol {
#[pest_ast(outer(with(span_into_str), with(String::from)))]
pub value: String,
}
#[derive(Debug, FromPest)]
#[pest_ast(rule(Rule::EOI))]
struct EOI;
}
fn main() {
use ast::Program;
use from_pest::FromPest;
use pest::Parser;
use std::fs;
let unparsed_file = fs::read_to_string("samples/sample1.code").expect("cannot read file");
let mut parse_tree =
parser::Parser::parse(parser::Rule::program, &unparsed_file).expect("unsuccessful parse");
println!("parse tree = {:#?}", parse_tree);
let syntax_tree: Program = Program::from_pest(&mut parse_tree).expect("infallible");
println!("syntax tree = {:#?}", syntax_tree);
// let tokens = program.
// for token in program.tokens() {
// println!("{:?}", token);
// }
// println!("{}", program)
// for statement in program.into_inner() {
// match statement.as_rule() {
// Rule::statement => {
// println!("{}", statement.as_str());
// }
// Rule::EOI => (),
// _ => unreachable!(),
// }
// }
// println!("Sum of fields: {}", field_sum);
// println!("Number of records: {}", record_count);
}
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