diff options
| -rw-r--r-- | src/compiler.rs | 102 | ||||
| -rw-r--r-- | src/tokenizer.rs | 2 | ||||
| -rw-r--r-- | src/vm.rs | 12 | ||||
| -rw-r--r-- | tests/simple.tdy | 11 |
4 files changed, 119 insertions, 8 deletions
diff --git a/src/compiler.rs b/src/compiler.rs index 345088f..6074660 100644 --- a/src/compiler.rs +++ b/src/compiler.rs @@ -1,4 +1,5 @@ use std::path::{Path, PathBuf}; +use std::convert::TryFrom; use crate::tokenizer::{Token, TokenStream}; use crate::vm::{Value, Block, Op}; @@ -45,10 +46,38 @@ nextable_enum!(Prec { Factor }); +enum Type { + UnkownType, + Int, + Float, + Bool, +} + +impl TryFrom<&str> for Type { + type Error = (); + + fn try_from(value: &str) -> Result<Self, Self::Error> { + match value { + "int" => Ok(Type::Int), + "float" => Ok(Type::Float), + "bool" => Ok(Type::Bool), + _ => Err(()), + } + } +} + +struct Variable { + name: String, + typ: Type, +} + struct Compiler { curr: usize, tokens: TokenStream, current_file: PathBuf, + + stack: Vec<Variable>, + panic: bool, errors: Vec<Error>, } @@ -59,6 +88,9 @@ impl Compiler { curr: 0, tokens, current_file: PathBuf::from(current_file), + + stack: vec![], + panic: false, errors: vec![], } @@ -90,13 +122,22 @@ impl Compiler { } fn peek(&self) -> Token { - if self.tokens.len() <= self.curr { + self.peek_at(0) + } + + fn peek_at(&self, at: usize) -> Token { + if self.tokens.len() <= self.curr + at { crate::tokenizer::Token::EOF } else { - self.tokens[self.curr].0.clone() + self.tokens[self.curr + at].0.clone() } } + // TODO(ed): Const generics + fn peek_four(&self) -> (Token, Token, Token, Token) { + (self.peek_at(0), self.peek_at(1), self.peek_at(2), self.peek_at(3)) + } + fn eat(&mut self) -> Token { let t = self.peek(); self.curr += 1; @@ -135,6 +176,7 @@ impl Compiler { fn prefix(&mut self, token: Token, block: &mut Block) -> bool { match token { + Token::Identifier(_) => self.variable_expression(block), Token::LeftParen => self.grouping(block), Token::Minus => self.unary(block), @@ -236,17 +278,69 @@ impl Compiler { } } + fn find_local(&self, name: &str, block: &Block) -> Option<usize> { + self.stack.iter() + .rev() + .enumerate() + .find_map(|x| if x.1.name == name { Some(x.0) } else { None} ) + } + + fn variable_expression(&mut self, block: &mut Block) { + let name = match self.eat() { + Token::Identifier(name) => name, + _ => unreachable!(), + }; + if let Some(id) = self.find_local(&name, block) { + block.add(Op::ReadLocal(id), self.line()); + } else { + error!(self, format!("Using undefined variable {}.", name)); + } + } + + fn define_variable(&mut self, name: &str, typ: Type, block: &mut Block) { + + if self.find_local(&name, block).is_some() { + error!(self, format!("Multiple definitions of {}.", name)); + return; + } + + self.expression(block); + + self.stack.push(Variable { name: String::from(name), typ }); + + // block.add(Op::Assign(self.stack.len() - 1), self.line()); + } + fn statement(&mut self, block: &mut Block) { self.clear_panic(); - match self.peek() { - Token::Print => { + match self.peek_four() { + (Token::Print, _, _, _) => { self.eat(); self.expression(block); block.add(Op::Print, self.line()); expect!(self, Token::Newline, "Expect newline after expression."); }, + (Token::Identifier(name), Token::Identifier(typ), Token::ColonEqual, _) => { + self.eat(); + self.eat(); + self.eat(); + if let Ok(typ) = Type::try_from(typ.as_ref()) { + self.define_variable(&name, typ, block); + } else { + error!(self, format!("Failed to parse type '{}'.", typ)); + } + expect!(self, Token::Newline, "Expect newline after expression."); + } + + (Token::Identifier(name), Token::ColonEqual, _, _) => { + self.eat(); + self.eat(); + self.define_variable(&name, Type::UnkownType, block); + expect!(self, Token::Newline, "Expect newline after expression."); + } + _ => { self.expression(block); block.add(Op::Pop, self.line()); diff --git a/src/tokenizer.rs b/src/tokenizer.rs index e360085..18e1aa1 100644 --- a/src/tokenizer.rs +++ b/src/tokenizer.rs @@ -56,6 +56,8 @@ pub enum Token { Colon, #[token("::")] ColonColon, + #[token(":=")] + ColonEqual, #[token("=")] Equal, #[token("==")] @@ -40,6 +40,10 @@ pub enum Op { AssertEqual, + ReadLocal(usize), + Assign(usize), + + Print, Return, } @@ -247,6 +251,14 @@ impl VM { self.stack.push(Value::Bool(a == b)); } + Op::ReadLocal(slot) => { + self.stack.push(self.stack[slot]); + } + + Op::Assign(slot) => { + self.stack[slot] = self.stack.pop().unwrap(); + } + Op::Print => { println!("PRINT: {:?}", self.stack.pop()); } diff --git a/tests/simple.tdy b/tests/simple.tdy index d38c6af..01dc5aa 100644 --- a/tests/simple.tdy +++ b/tests/simple.tdy @@ -1,4 +1,7 @@ -1 + 1 <=> 2 -// asdlkjasl -print 1 + 3 -// OwO +// 1 + 1 <=> 2 +// // asdlkjasl +// print 1 + 3 +// // OwO +a int := 1 +print a +print a + a + a |