public object visitSuperExpr(Expr.Super expr)
{
if (currentClass == ClassType.NONE)
{
Lox.error(expr.keyword, "Cannot use 'super' outside of a class.");
}
else if (currentClass != ClassType.SUBCLASS)
{
Lox.error(expr.keyword, "Cannot use 'super' in a class with no superclass.");
}
resolveLocal(expr, expr.keyword);
return(null);
}
public object visitSuperExpr(Expr.Super expr)
{
int distance = locals[expr];
LoxClass superclass = (LoxClass)environment.getAt(distance, "super");
// "this" is always one level nearer than "super"'s environment
LoxInstance object_ = (LoxInstance)environment.getAt(distance - 1, "this");
LoxFunction method = superclass.findMethod(expr.method.lexeme);
if (method == null)
{
throw new RuntimeError(expr.method, "Undefined property '" + expr.method.lexeme + "'.");
}
return(method.bind(object_));
}
public string visitSuperExpr(Expr.Super expr)
{
return("");
}