Window.draw no instance of overloaded function

[Jadw1]

Hi, I have a problem with drawing my drawable object.

So:
I have a class that implements sf::Drawable
Node.h

#pragma once
#include <SFML/Graphics.hpp>
class Node : public sf::Drawable {
private:
virtual void draw(sf::RenderTarget& target, sf::RenderStates status) const;
}
 

Node.cpp

#include "Node.h"

void Node::draw(sf::RenderTarget& target, sf::RenderStates status) const {
sf::RectangleShape rect(...);
target.draw(rect);
}
 

In my app class, where I have pointer to window i have

Node node();

/* in loop */
...
_window->draw(node);
...
 

and there I have that error:

[FRex]

Variable 'node' type is 'Node()' not 'Node'.

Remove '()' after 'node' from the 'Node node();' line.

This is a common C++ trap: https://en.wikipedia.org/wiki/Most_vexing_parse

[Laurent]

Note that the "most vexing parse" is more specific, as shown in the wikipedia article. Here he just declared a function thinking it was a default-constructed instance, but it's more a developer oversight than a language trick

[FRex]

It's not very specific, it's not a trick, it's an ambiguity in the syntax, it's whenever something surprising arises from the C++ rule that says anything looking like a function is parsed as a function. Herb Sutter even lists trying to call default constructor as one in b): https://herbsutter.com/2013/05/09/gotw-1-solution/

Clang's -Wvexing-parse warns against this too:

[ff@localhost a]$ cat a.cpp
class Wat {};
int main()
{
    Wat wat();
}
[ff@localhost a]$ clang++ -Wvexing-parse a.cpp
a.cpp:4:12: warning: empty parentheses interpreted as a function declaration [-Wvexing-parse]
    Wat wat();
           ^~
a.cpp:4:12: note: remove parentheses to declare a variable
    Wat wat();
           ^~
1 warning generated.