Update parse orders a bit

This commit is contained in:
Sofia 2020-06-22 16:58:42 +03:00
parent c9dffa7713
commit 3414aaee9b
4 changed files with 77 additions and 51 deletions

View File

@ -18,22 +18,38 @@ impl From<io::Error> for GenericError {
pub enum CompilerError {
Fatal,
ExpectedToken(Position, char),
ExpectedExpression(Position, Box<CompilerError>),
ExpectedExpression(Position, Option<Box<CompilerError>>),
ExpectedIdent(Position),
ExpectedStatement(Position),
ExpectedStatement(Position, Option<Box<CompilerError>>),
ExpectedPattern(Position),
}
impl CompilerError {
fn from_opt(from: &Option<Box<CompilerError>>) -> String {
if let Some(err) = from {
format!("\n {}", err)
} else {
String::new()
}
}
}
impl Display for CompilerError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let text = match self {
CompilerError::Fatal => "Fatal error".to_string(),
CompilerError::ExpectedToken(pos, c) => format!("Expected token '{}' at {}", c, pos),
CompilerError::ExpectedExpression(pos, err) => {
format!("Expected expression at {}.\n {}", pos, err)
}
CompilerError::ExpectedExpression(pos, err) => format!(
"Expected expression at {}{}",
pos,
CompilerError::from_opt(err)
),
CompilerError::ExpectedIdent(pos) => format!("Expected ident at {}", pos),
CompilerError::ExpectedStatement(pos) => format!("Expected statement at {}", pos),
CompilerError::ExpectedStatement(pos, err) => format!(
"Expected statement at {}{}",
pos,
CompilerError::from_opt(err)
),
CompilerError::ExpectedPattern(pos) => format!("Expected pattern at {}", pos),
};
write!(f, "{}", text)

View File

@ -13,4 +13,5 @@ fn main() {
eprintln!("Syntax error: {}", error);
std::process::exit(1);
}
dbg!(reid);
}

View File

@ -1,7 +1,7 @@
mod parsed_reid;
use super::errors::CompilerError;
use parsed_reid::{Expression, ParsedReid};
use parsed_reid::{Expression, ParsedReid, Statement};
use std::fmt;
use std::fmt::Display;
@ -32,16 +32,16 @@ impl Parser {
}
pub fn parse(mut self) -> Result<ParsedReid, CompilerError> {
let mut exp_list = Vec::new();
let mut statement_list = Vec::new();
let mut error = None;
while {
self.skip_whitespace();
if self.remaining() > 0 {
match Expression::parse(&mut self) {
match Statement::parse(&mut self) {
Ok(exp) => {
exp_list.push(exp);
statement_list.push(exp);
true
}
Err(err) => {
@ -57,7 +57,10 @@ impl Parser {
if let Some(error) = error {
Err(error)
} else {
Ok(ParsedReid(Expression::BlockExpr(Position(0, 0), exp_list)))
Ok(ParsedReid(Expression::BlockExpr(
Position(0, 0),
statement_list,
)))
}
}

View File

@ -4,47 +4,11 @@ type Ident = String;
#[derive(Debug)]
pub struct ParsedReid(pub Expression);
#[derive(Debug)]
pub enum Expression {
BlockExpr(Position, Vec<Expression>),
StatementExpr(Position, Statement),
}
impl Expression {
pub fn parse(parser: &mut Parser) -> Result<Expression, CompilerError> {
let begin_pos = parser.pos();
let expect = parser.expect("{");
if let Some(_) = expect.get() {
let mut exp_list = Vec::new();
while {
match Expression::parse(parser) {
Ok(exp) => {
exp_list.push(exp);
true
}
Err(_) => false,
}
} {}
if let Some(_) = parser.expect("}").get() {
Ok(Expression::BlockExpr(begin_pos, exp_list))
} else {
Err(CompilerError::ExpectedToken(parser.pos(), '}'))
}
} else {
match Statement::parse(parser) {
Ok(statement) => Ok(Expression::StatementExpr(begin_pos, statement)),
Err(err) => Err(CompilerError::ExpectedExpression(begin_pos, Box::new(err))),
}
}
}
}
#[derive(Debug)]
pub enum Statement {
LetStatement(Position, Ident, Box<Expression>),
ValueRef(Position, Pattern),
ExprStatement(Position, Expression),
}
impl Statement {
@ -65,12 +29,54 @@ impl Statement {
.get_or(CompilerError::ExpectedToken(pos, ';'))?;
Ok(Statement::LetStatement(pos, ident, Box::new(expr)))
}
Err(err) => Err(CompilerError::ExpectedExpression(pos, Box::new(err))),
Err(err) => Err(CompilerError::ExpectedExpression(pos, Some(Box::new(err)))),
}
} else {
match Expression::parse(parser) {
Ok(expr) => {
let statement = Statement::ExprStatement(pos, expr);
parser
.expect(";")
.get_or(CompilerError::ExpectedToken(pos, ';'))?;
Ok(statement)
}
Err(err) => Err(CompilerError::ExpectedStatement(pos, Some(Box::new(err)))),
}
}
}
}
#[derive(Debug)]
pub enum Expression {
BlockExpr(Position, Vec<Statement>),
ValueRef(Position, Pattern),
}
impl Expression {
pub fn parse(parser: &mut Parser) -> Result<Expression, CompilerError> {
let begin_pos = parser.pos();
let expect = parser.expect("{");
if let Some(_) = expect.get() {
let mut statement_list = Vec::new();
while {
match Statement::parse(parser) {
Ok(exp) => {
statement_list.push(exp);
true
}
Err(_) => false,
}
} {}
if let Some(_) = parser.expect("}").get() {
Ok(Expression::BlockExpr(begin_pos, statement_list))
} else {
Err(CompilerError::ExpectedToken(parser.pos(), '}'))
}
} else if let Ok(pattern) = Pattern::parse(parser) {
Ok(Statement::ValueRef(pos, pattern))
Ok(Expression::ValueRef(begin_pos, pattern))
} else {
Err(CompilerError::ExpectedStatement(pos))
Err(CompilerError::ExpectedExpression(begin_pos, None))
}
}
}