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Getting type for a template

Lowest0ne (1536)
How might one go about solving this problem?
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unknownType func( void );
std::vector<  /* type of unknownType */ > objects


The source of my question is trying to make a templated button:
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template <typename T>
class Button
{
  T m_func;

  void onClick( void ) { m_func(); }
};

class Controller
{
  void updateSomething( void );
  
  Button< /* type of updateSomething */ > updateSomethingButton;
};


Thanks
Last edited on
closed account (o1vk4iN6)
Well you'd have to make updateSomething a static function otherwise you'd have to send a Controller object to button.

Are you trying to use this as a callback for when the button is pressed ? It might be better not to template this and simply provide a specific function type to be called:

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Button<void (*)(int)> button; // what now... what gets sent to int.

// ...

void Button<T>::onClick() { m_func(); } // err


or simply:

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class Button
{
public:
    using Function = std::function<void()>;

    Button(Function callback) : m_callback(callback) { }

private:

    Function m_callback;

    void onClick() { m_callback(); } // since this will always have to be void() anyways

};

class Controller
{
public:
    Controller() : button(std::bind(&Controller::updateSomething, this)) { }

private:
    Button button;

    void updateSomething() { }

};


Lowest0ne (1536)
Thanks xerzi, I didn't realize that std::function<void()> would be able to handle the case of a this.
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