public object VisitFunctionStmt(Stmt.Function stmt) { BasilFunction function = new BasilFunction(stmt, environment, false); environment.Define(stmt.name.lexeme, function); return(null); }
public object VisitClassStmt(Stmt.Class stmt) { environment.Define(stmt.Name.lexeme, null); object superclass = null; if (stmt.Superclass != null) { superclass = Evaluate(stmt.Superclass); if (!(superclass is BasilClass)) { throw new RuntimeError(stmt.Name, "Superclass must be a class."); } environment = new Environment(environment); environment.Define("super", superclass); } Dictionary <string, BasilFunction> methods = new Dictionary <string, BasilFunction>(); foreach (var method in stmt.Methods) { BasilFunction function = new BasilFunction(method, environment, method.name.lexeme.Equals("init")); methods.Add(method.name.lexeme, function); } BasilClass klass = new BasilClass(stmt.Name.lexeme, (BasilClass)superclass, methods); if (superclass != null) { environment = environment.Enclosing; } environment.Assign(stmt.Name, klass); return(null); }
public object VisitSuperExpr(Expr.Super expr) { int distance = locals[expr]; BasilClass superclass = (BasilClass)environment.GetAt(distance, "super"); // "this" is always one level nearer than "super"'s environment. BasilInstance objekt = (BasilInstance)environment.GetAt(distance - 1, "this"); BasilFunction method = superclass.FindMethod(objekt, expr.Method.lexeme); if (method == null) { throw new RuntimeError(expr.Method, $"Undefined property '{expr.Method.lexeme}'."); } return(method); }
public object Get(Token name) { if (fields.ContainsKey(name.lexeme)) { return(fields[name.lexeme]); } BasilFunction method = klass.FindMethod(this, name.lexeme); if (method != null) { return(method); } throw new RuntimeError(name, $"Undefined property '{name.lexeme}'."); }