use super::chunk::Chunk; use super::errors::{Error, ErrorKind, LoxResult}; use super::opcode::OpCode; use crate::scanner; struct Compiler> { // panic: bool, errors: Vec, tokens: T, chunk: Chunk, // TODO(tazjin): Restructure so that these don't need to be Option? current: Option, previous: Option, } impl> Compiler { fn compile(&mut self) -> LoxResult<()> { self.advance(); self.expression(); self.consume( &scanner::TokenKind::Eof, ErrorKind::ExpectedToken("Expected end of expression"), )?; self.end_compiler() } fn advance(&mut self) { self.previous = self.current.take(); self.current = self.tokens.next(); } fn expression(&mut self) { unimplemented!() } fn consume( &mut self, expected: &scanner::TokenKind, err: ErrorKind, ) -> LoxResult<()> { unimplemented!() } fn current_chunk(&mut self) -> &mut Chunk { &mut self.chunk } fn end_compiler(&mut self) -> LoxResult<()> { let line = self.previous().line; self.current_chunk().add_op(OpCode::OpReturn, line); Ok(()) } fn previous(&self) -> &scanner::Token { self.previous .as_ref() .expect("invalid internal compiler state: missing previous token") } } pub fn compile(code: &str) -> Result> { let chars = code.chars().collect::>(); let tokens = scanner::scan(&chars).map_err(|errors| { errors.into_iter().map(Into::into).collect::>() })?; let mut compiler = Compiler { tokens: tokens.into_iter().peekable(), errors: vec![], current: None, previous: None, chunk: Default::default(), }; compiler.compile()?; if compiler.errors.is_empty() { Ok(unimplemented!()) } else { Err(compiler.errors) } }