private Stmt ForStatement() { Consume(LEFT_PAREN, "Expect '(' after 'for'."); // For loop doesn't get its own statement. // Instead we desugar and reduce it to a while loop. Stmt initializer; if (Match(SEMICOLON)) { initializer = null; } else if (Match(VAR)) { initializer = VarDeclaration(); } else { initializer = ExpressionStatement(); } Expr condition = null; if (!IsCurrentTokenType(SEMICOLON)) { condition = Expression(); } Consume(SEMICOLON, "Expect ';' after loop condition."); Expr increment = null; if (!IsCurrentTokenType(RIGHT_PAREN)) { increment = Expression(); } Consume(RIGHT_PAREN, "Expect ')' after for clauses."); // Parse the statement body of the for loop. Stmt body = Statement(); if (increment != null) { // Add increment to be executed after the main body. body = new Stmt.Block(new List <Stmt> { body, new Stmt.Expression(increment) }); } if (condition == null) { condition = new Expr.Literal(true); } body = new Stmt.While(condition, body); if (initializer != null) { // Run the initializer once before the while loop. body = new Stmt.Block(new List <Stmt> { initializer, body }); } return(body); }
private Stmt forStatement() { consume(TokenType.LEFT_PAREN, "Expect '(' after 'for'."); Stmt initializer; if (match(TokenType.SEMICOLON)) { initializer = null; } else if (match(TokenType.VAR)) { initializer = varDeclaration(); } else { initializer = expressionStatement(); } Expr condition = null; if (!check(TokenType.SEMICOLON)) { condition = expression(); } consume(TokenType.SEMICOLON, "Expect ';' after loop condition."); Expr increment = null; if (!check(TokenType.RIGHT_PAREN)) { increment = expression(); } consume(TokenType.RIGHT_PAREN, "Expect ')' after for clauses."); Stmt body = statement(); if (increment != null) { body = new Stmt.Block(new List <Stmt> { body, new Stmt.Expression(increment), }); } if (condition == null) { condition = new Expr.Literal(true); } body = new Stmt.While(condition, body); if (initializer != null) { body = new Stmt.Block(new List <Stmt> { initializer, body }); } return(body); }
public object VisitWhileStmt(Stmt.While stmt) { Resolve(stmt.condition); Resolve(stmt.body); return(null); }
public Void VisitWhileStmt(Stmt.While stmt) { Resolve(stmt.Condition); Resolve(stmt.Body); return(null); }
public string VisitWhileStmt(Stmt.While stmt) { throw new NotImplementedException(); }
public string VisitWhileStmt(Stmt.While stmt) => throw new System.NotImplementedException();
private Stmt ForStatement() { Consume(LEFT_PAREN, "Expect '(' after 'for'."); Stmt initializer; if (Match(SEMICOLON)) { initializer = null; } else if (Match(VAR)) { initializer = VarDeclaration(); } else { initializer = ExpressionStatement(); } Expr condition = null; if (!Check(SEMICOLON)) { condition = Expression(); } Consume(SEMICOLON, "Expect ';' after loop condition."); Expr increment = null; if (!Check(RIGHT_PAREN)) { increment = Expression(); } Consume(RIGHT_PAREN, "Expect ')' after for clauses."); var body = Statement(); if (increment != null) { body = new Stmt.Block(new List <Stmt>() { body, new Stmt.Expression(increment) }); } if (condition == null) { condition = new Expr.Literal(true); } body = new Stmt.While(condition, body); if (initializer != null) { body = new Stmt.Block(new List <Stmt>() { initializer, body }); } return(body); }