public object VisitAssignExpr(Assign expr) { object value = Evaluate(expr.Value); if (locals.TryGetValue(expr, out int distance)) { environment.AssignAt(distance, expr.Name, value); } else { Globals.Assign(expr.Name, value); } return(value); }
public void Assign(Token name, object value) { if (values.ContainsKey(name.Lexeme)) { values[name.Lexeme] = value; return; } if (Enclosing != null) { Enclosing.Assign(name, value); return; } throw new RuntimeException(name, $"Undefined variable '{name.Lexeme}'."); }
public object VisitClassStmt(Class stmt) { object superclass = null; if (stmt.Superclass != null) { superclass = Evaluate(stmt.Superclass); if (!(superclass is LoxClass)) { throw new RuntimeException(stmt.Superclass.Name, "Superclass must be a class."); } } environment.Define(stmt.Name.Lexeme, null); if (stmt.Superclass != null) { environment = new LoxEnvironment(environment); environment.Define("super", superclass); } Dictionary <string, LoxFunction> methods = new Dictionary <string, LoxFunction>(); foreach (Function method in stmt.Methods) { LoxFunction function = new LoxFunction(method, environment, method.Name.Lexeme.Equals("init")); methods.Add(method.Name.Lexeme, function); } LoxClass @class = new LoxClass(stmt.Name.Lexeme, (LoxClass)superclass, methods); if (superclass != null) { environment = environment.Enclosing; } environment.Assign(stmt.Name, @class); return(null); }