diff options
Diffstat (limited to 'users/tazjin/rlox/src/treewalk')
| -rw-r--r-- | users/tazjin/rlox/src/treewalk/interpreter.rs | 106 | ||||
| -rw-r--r-- | users/tazjin/rlox/src/treewalk/parser.rs | 122 | ||||
| -rw-r--r-- | users/tazjin/rlox/src/treewalk/resolver.rs | 43 |
3 files changed, 91 insertions, 180 deletions
diff --git a/users/tazjin/rlox/src/treewalk/interpreter.rs b/users/tazjin/rlox/src/treewalk/interpreter.rs index d9fe33661684..3285775bbec6 100644 --- a/users/tazjin/rlox/src/treewalk/interpreter.rs +++ b/users/tazjin/rlox/src/treewalk/interpreter.rs @@ -34,11 +34,7 @@ impl Callable { } } - fn call( - &self, - lox: &mut Interpreter, - args: Vec<Value>, - ) -> Result<Value, Error> { + fn call(&self, lox: &mut Interpreter, args: Vec<Value>) -> Result<Value, Error> { match self { Callable::Builtin(builtin) => builtin.call(args), @@ -50,10 +46,8 @@ impl Callable { fn_env.define(param, value)?; } - let result = lox.interpret_block_with_env( - Some(Rc::new(RwLock::new(fn_env))), - &func.body, - ); + let result = + lox.interpret_block_with_env(Some(Rc::new(RwLock::new(fn_env))), &func.body); match result { // extract returned values if applicable @@ -109,22 +103,13 @@ pub struct Environment { } impl Environment { - fn define( - &mut self, - name: &scanner::Token, - value: Value, - ) -> Result<(), Error> { + fn define(&mut self, name: &scanner::Token, value: Value) -> Result<(), Error> { let ident = identifier_str(name)?; self.values.insert(ident.into(), value); Ok(()) } - fn get( - &self, - ident: &str, - line: usize, - depth: usize, - ) -> Result<Value, Error> { + fn get(&self, ident: &str, line: usize, depth: usize) -> Result<Value, Error> { if depth > 0 { match &self.enclosing { None => { @@ -137,9 +122,7 @@ impl Environment { }) } Some(parent) => { - let env = parent - .read() - .expect("fatal: environment lock poisoned"); + let env = parent.read().expect("fatal: environment lock poisoned"); return env.get(ident, line, depth - 1); } } @@ -154,11 +137,7 @@ impl Environment { }) } - fn assign( - &mut self, - name: &scanner::Token, - value: Value, - ) -> Result<(), Error> { + fn assign(&mut self, name: &scanner::Token, value: Value) -> Result<(), Error> { let ident = identifier_str(name)?; match self.values.get_mut(ident) { @@ -242,22 +221,14 @@ impl Lox for Interpreter { impl Interpreter { // Environment modification helpers - fn define_var( - &mut self, - name: &scanner::Token, - value: Value, - ) -> Result<(), Error> { + fn define_var(&mut self, name: &scanner::Token, value: Value) -> Result<(), Error> { self.env .write() .expect("environment lock is poisoned") .define(name, value) } - fn assign_var( - &mut self, - name: &scanner::Token, - value: Value, - ) -> Result<(), Error> { + fn assign_var(&mut self, name: &scanner::Token, value: Value) -> Result<(), Error> { self.env .write() .expect("environment lock is poisoned") @@ -271,11 +242,10 @@ impl Interpreter { kind: ErrorKind::UndefinedVariable(ident.into()), })?; - self.env.read().expect("environment lock is poisoned").get( - ident, - var.name.line, - depth, - ) + self.env + .read() + .expect("environment lock is poisoned") + .get(ident, var.name.line, depth) } /// Interpret the block in the supplied environment. If no @@ -324,16 +294,10 @@ impl Interpreter { Value::Literal(Literal::String(output)) } Statement::Var(var) => return self.interpret_var(var), - Statement::Block(block) => { - return self.interpret_block_with_env(None, block) - } + Statement::Block(block) => return self.interpret_block_with_env(None, block), Statement::If(if_stmt) => return self.interpret_if(if_stmt), - Statement::While(while_stmt) => { - return self.interpret_while(while_stmt) - } - Statement::Function(func) => { - return self.interpret_function(func.clone()) - } + Statement::While(while_stmt) => return self.interpret_while(while_stmt), + Statement::Function(func) => return self.interpret_function(func.clone()), Statement::Return(ret) => { return Err(Error { line: 0, @@ -348,9 +312,7 @@ impl Interpreter { fn interpret_var(&mut self, var: &parser::Var) -> Result<Value, Error> { let init = var.initialiser.as_ref().ok_or_else(|| Error { line: var.name.line, - kind: ErrorKind::InternalError( - "missing variable initialiser".into(), - ), + kind: ErrorKind::InternalError("missing variable initialiser".into()), })?; let value = self.eval(init)?; self.define_var(&var.name, value.clone())?; @@ -369,10 +331,7 @@ impl Interpreter { } } - fn interpret_while( - &mut self, - stmt: &parser::While, - ) -> Result<Value, Error> { + fn interpret_while(&mut self, stmt: &parser::While) -> Result<Value, Error> { let mut value = Value::Literal(Literal::Nil); while eval_truthy(&self.eval(&stmt.condition)?) { value = self.interpret_stmt(&stmt.body)?; @@ -381,10 +340,7 @@ impl Interpreter { Ok(value) } - fn interpret_function( - &mut self, - func: Rc<parser::Function>, - ) -> Result<Value, Error> { + fn interpret_function(&mut self, func: Rc<parser::Function>) -> Result<Value, Error> { let name = func.name.clone(); let value = Value::Callable(Callable::Function { func, @@ -414,9 +370,7 @@ impl Interpreter { (TokenKind::Minus, Value::Literal(Literal::Number(num))) => { Ok(Literal::Number(-num).into()) } - (TokenKind::Bang, right) => { - Ok(Literal::Boolean(!eval_truthy(&right)).into()) - } + (TokenKind::Bang, right) => Ok(Literal::Boolean(!eval_truthy(&right)).into()), (op, right) => Err(Error { line: expr.operator.line, @@ -478,10 +432,7 @@ impl Interpreter { Ok(value) } - fn eval_logical( - &mut self, - logical: &parser::Logical, - ) -> Result<Value, Error> { + fn eval_logical(&mut self, logical: &parser::Logical) -> Result<Value, Error> { let left = eval_truthy(&self.eval(&logical.left)?); let right = eval_truthy(&self.eval(&logical.right)?); @@ -490,10 +441,7 @@ impl Interpreter { TokenKind::Or => Ok(Literal::Boolean(left || right).into()), kind => Err(Error { line: logical.operator.line, - kind: ErrorKind::InternalError(format!( - "Invalid logical operator: {:?}", - kind - )), + kind: ErrorKind::InternalError(format!("Invalid logical operator: {:?}", kind)), }), } } @@ -504,10 +452,7 @@ impl Interpreter { Value::Literal(v) => { return Err(Error { line: call.paren.line, - kind: ErrorKind::RuntimeError(format!( - "not callable: {:?}", - v - )), + kind: ErrorKind::RuntimeError(format!("not callable: {:?}", v)), }) } }; @@ -546,10 +491,7 @@ fn eval_truthy(lit: &Value) -> bool { } } -fn set_enclosing_env( - this: &RwLock<Environment>, - parent: Rc<RwLock<Environment>>, -) { +fn set_enclosing_env(this: &RwLock<Environment>, parent: Rc<RwLock<Environment>>) { this.write() .expect("environment lock is poisoned") .enclosing = Some(parent); diff --git a/users/tazjin/rlox/src/treewalk/parser.rs b/users/tazjin/rlox/src/treewalk/parser.rs index 003cc34b4665..5794b42d1577 100644 --- a/users/tazjin/rlox/src/treewalk/parser.rs +++ b/users/tazjin/rlox/src/treewalk/parser.rs @@ -124,56 +124,54 @@ pub enum Statement { // Parser -/* -program → declaration* EOF ; - -declaration → funDecl - | varDecl - | statement ; - -funDecl → "fun" function ; -function → IDENTIFIER "(" parameters? ")" block ; -parameters → IDENTIFIER ( "," IDENTIFIER )* ; - - -statement → exprStmt - | forStmt - | ifStmt - | printStmt - | returnStmt - | whileStmt - | block ; - -forStmt → "for" "(" ( varDecl | exprStmt | ";" ) - expression? ";" - expression? ")" statement ; - -returnStmt → "return" expression? ";" ; - -whileStmt → "while" "(" expression ")" statement ; - -exprStmt → expression ";" ; - -ifStmt → "if" "(" expression ")" statement - ( "else" statement )? ; - -printStmt → "print" expression ";" ; - -expression → assignment ; -assignment → IDENTIFIER "=" assignment - | logic_or ; -logic_or → logic_and ( "or" logic_and )* ; -logic_and → equality ( "and" equality )* ; -equality → comparison ( ( "!=" | "==" ) comparison )* ; -comparison → term ( ( ">" | ">=" | "<" | "<=" ) term )* ; -term → factor ( ( "-" | "+" ) factor )* ; -factor → unary ( ( "/" | "*" ) unary )* ; -unary → ( "!" | "-" ) unary | call ; -call → primary ( "(" arguments? ")" )* ; -arguments → expression ( "," expression )* ; -primary → NUMBER | STRING | "true" | "false" | "nil" - | "(" expression ")" ; -*/ +// program → declaration* EOF ; +// +// declaration → funDecl +// | varDecl +// | statement ; +// +// funDecl → "fun" function ; +// function → IDENTIFIER "(" parameters? ")" block ; +// parameters → IDENTIFIER ( "," IDENTIFIER )* ; +// +// +// statement → exprStmt +// | forStmt +// | ifStmt +// | printStmt +// | returnStmt +// | whileStmt +// | block ; +// +// forStmt → "for" "(" ( varDecl | exprStmt | ";" ) +// expression? ";" +// expression? ")" statement ; +// +// returnStmt → "return" expression? ";" ; +// +// whileStmt → "while" "(" expression ")" statement ; +// +// exprStmt → expression ";" ; +// +// ifStmt → "if" "(" expression ")" statement +// ( "else" statement )? ; +// +// printStmt → "print" expression ";" ; +// +// expression → assignment ; +// assignment → IDENTIFIER "=" assignment +// | logic_or ; +// logic_or → logic_and ( "or" logic_and )* ; +// logic_and → equality ( "and" equality )* ; +// equality → comparison ( ( "!=" | "==" ) comparison )* ; +// comparison → term ( ( ">" | ">=" | "<" | "<=" ) term )* ; +// term → factor ( ( "-" | "+" ) factor )* ; +// factor → unary ( ( "/" | "*" ) unary )* ; +// unary → ( "!" | "-" ) unary | call ; +// call → primary ( "(" arguments? ")" )* ; +// arguments → expression ( "," expression )* ; +// primary → NUMBER | STRING | "true" | "false" | "nil" +// | "(" expression ")" ; struct Parser { tokens: Vec<Token>, @@ -213,9 +211,7 @@ impl Parser { if params.len() >= 255 { return Err(Error { line: self.peek().line, - kind: ErrorKind::InternalError( - "255 parameter limit exceeded.".into(), - ), + kind: ErrorKind::InternalError("255 parameter limit exceeded.".into()), }); } @@ -429,10 +425,7 @@ impl Parser { return Err(Error { line: equals.line, - kind: ErrorKind::InvalidAssignmentTarget(format!( - "{:?}", - equals - )), + kind: ErrorKind::InvalidAssignmentTarget(format!("{:?}", equals)), }); } @@ -495,9 +488,7 @@ impl Parser { } fn unary(&mut self) -> ExprResult { - if self.match_token(&TokenKind::Bang) - || self.match_token(&TokenKind::Minus) - { + if self.match_token(&TokenKind::Bang) || self.match_token(&TokenKind::Minus) { return Ok(Expr::Unary(Unary { operator: self.previous().clone(), right: Box::new(self.unary()?), @@ -557,10 +548,7 @@ impl Parser { TokenKind::LeftParen => { let expr = self.expression()?; - self.consume( - &TokenKind::RightParen, - ErrorKind::UnmatchedParens, - )?; + self.consume(&TokenKind::RightParen, ErrorKind::UnmatchedParens)?; return Ok(Expr::Grouping(Grouping(Box::new(expr)))); } @@ -632,11 +620,7 @@ impl Parser { &self.tokens[self.current - 1] } - fn consume( - &mut self, - kind: &TokenKind, - err: ErrorKind, - ) -> Result<Token, Error> { + fn consume(&mut self, kind: &TokenKind, err: ErrorKind) -> Result<Token, Error> { if self.check_token(kind) { return Ok(self.advance()); } diff --git a/users/tazjin/rlox/src/treewalk/resolver.rs b/users/tazjin/rlox/src/treewalk/resolver.rs index 8231ce5a9e58..3d12973aa089 100644 --- a/users/tazjin/rlox/src/treewalk/resolver.rs +++ b/users/tazjin/rlox/src/treewalk/resolver.rs @@ -56,13 +56,14 @@ impl<'a> Resolver<'a> { // The resolver does not clone references, so unless // the interpreter is called before the resolver this // case should never happen. - None => return Err(Error { - line: 0, - kind: ErrorKind::InternalError( - "multiple function references before interpretation" - .into(), - ), - }), + None => { + return Err(Error { + line: 0, + kind: ErrorKind::InternalError( + "multiple function references before interpretation".into(), + ), + }) + } }, } } @@ -79,10 +80,7 @@ impl<'a> Resolver<'a> { Ok(()) } - fn resolve_function( - &mut self, - func: &'a mut parser::Function, - ) -> Result<(), Error> { + fn resolve_function(&mut self, func: &'a mut parser::Function) -> Result<(), Error> { self.declare(&func.name.lexeme); self.define(&func.name.lexeme); @@ -123,17 +121,13 @@ impl<'a> Resolver<'a> { } } - fn resolve_variable( - &mut self, - var: &'a mut parser::Variable, - ) -> Result<(), Error> { + fn resolve_variable(&mut self, var: &'a mut parser::Variable) -> Result<(), Error> { if let Some(scope) = self.scopes.last_mut() { if let Some(false) = scope.get(var.name.lexeme.as_str()) { return Err(Error { line: var.name.line, kind: ErrorKind::StaticError( - "can't read local variable in its own initialiser" - .into(), + "can't read local variable in its own initialiser".into(), ), }); } @@ -143,10 +137,7 @@ impl<'a> Resolver<'a> { Ok(()) } - fn resolve_assign( - &mut self, - assign: &'a mut parser::Assign, - ) -> Result<(), Error> { + fn resolve_assign(&mut self, assign: &'a mut parser::Assign) -> Result<(), Error> { self.resolve_expr(&mut assign.value)?; assign.depth = self.resolve_local(&assign.name); Ok(()) @@ -162,10 +153,7 @@ impl<'a> Resolver<'a> { None } - fn resolve_call( - &mut self, - call: &'a mut parser::Call, - ) -> Result<(), Error> { + fn resolve_call(&mut self, call: &'a mut parser::Call) -> Result<(), Error> { self.resolve_expr(&mut call.callee)?; for arg in call.args.iter_mut() { @@ -198,10 +186,7 @@ impl<'a> Resolver<'a> { } } -pub fn resolve( - globals: &[String], - block: &mut parser::Block, -) -> Result<(), Error> { +pub fn resolve(globals: &[String], block: &mut parser::Block) -> Result<(), Error> { let mut resolver: Resolver = Default::default(); // Scope for static globals only starts, never ends. |