return single object from unique_ptr vector in c-CodePudding

I'm making a command applaction I have base class that other commands class inherate.

struct BaseCommand {
public:
    virtual ~BaseCommand() {}
    int id = 0;
    std::string name = "Base Command";
    std::string description = "Base Command";
    BaseCommand();
    virtual std::string getName();
    virtual int getId();
    virtual std::string getDescription();
private:
    virtual void init();
    virtual void run();
    
};

class HelpCommand: public BaseCommand {
public:
    HelpCommand();
    std::string name = "help";
    std::string description = "output help";
    int id = 1;
    virtual std::string getName();
    int getId() {return this->id;}; 
    virtual std::string getDescription();
    
private:
    virtual void init();
    virtual void run();
};

class ProductCommand: public BaseCommand {
public:
    ProductCommand();
    std::string name = "prod";
    std::string description = "product";
    int id = 2;
    virtual std::string getName();
    int getId() {return this->id;};
    virtual std::string getDescription();
    
private:
    virtual void init();
    virtual void run();
};

and in my main, I push my subclass to a vector. my goal is to get the command by its name how do I do that and get the only command and assign it to a variable

    std::vector<std::unique_ptr<BaseCommand>> commands;
    // lett's push our commands...
    commands.emplace_back(new HelpCommand);
    commands.emplace_back(new ProductCommand);
    std::string command = 'prod';

    // what's the type should be for selectedCommand?
    ?? selectedCommand;

    for (int i = 0; i < commands.size();   i) {
        if (commands[i]->getName() == command) {
             selectedCommand = commands[i];
        }
   }

I can't seem to determine which type should the selectedCommand be. please what I'm missing here?

CodePudding user response：

You can't "override" member variables.

Your derived classes have two of each member variable with the same name; one in the base class and one in the derived class.
When you access the objects through a pointer to BaseCommand, you get the members from BaseCommand and not those from the dervied class.

Redesign so these are only members of the base, and make the accessors non-virtual:

struct BaseCommand {
public:
    virtual ~BaseCommand() {}
    const std::string& getName() const { return name; }
    int getId() const { return id; }
    const std::string& getDescription() const { return description; }

protected:
    // Let only derived classes create base instances.
    BaseCommand(int id,
                const std::string& name,
                const std::string& description)
        : id(id), name(name), description(description)
    {}

private:
    int id = 0;
    std::string name = "Base Command";
    std::string description = "Base Command";

    virtual void init();
    virtual void run();
};

class HelpCommand: public BaseCommand {
public:
    HelpCommand() : BaseCommand(1, "help", "output help") {}
private:
    virtual void init();
    virtual void run();
};
class ProductCommand: public BaseCommand {
public:
    ProductCommand() : BaseCommand(2, "prod", "product") {}
private:
    virtual void init();
    virtual void run();
};