Declaring Multiple Object Pointers on One Line: Unraveling the Compiler Error

When declaring multiple object pointers on the same line, developers often encounter a common issue that may lead to compiler errors. Understanding the root cause of this issue is crucial to ensure correct code execution.

Consider the following class declaration:

public:
    Entity()
    {
        re_sprite_eyes = new sf::Sprite();
        re_sprite_hair = new sf::Sprite();
        re_sprite_body = new sf::Sprite();
    }

private:
    sf::Sprite* re_sprite_hair;
    sf::Sprite* re_sprite_body;
    sf::Sprite* re_sprite_eyes;

In this case, declaring each pointer separately ensures correct functionality. However, when attempting to condense the declarations into a single line:

private:
    sf::Sprite* re_sprite_hair, re_sprite_body, re_sprite_eyes;

the compiler raises an error:

error: no match for 'operator=' in '((Entity*)this)->Entity::re_sprite_eyes = (operator new(272u), (<statement>, ((sf::Sprite*)<anonymous>)))

The key to understanding this error lies in the purpose of the asterisk (*) operator. In C , the asterisk can indicate either a pointer or a dereference operation. In this instance, the asterisk should indicate pointers to sf::Sprite objects. However, the declaration above incorrectly interprets the asterisk as applying to re_sprite_body and re_sprite_eyes, creating objects rather than pointers.

To resolve this issue, the correct syntax is:

sf::Sprite *re_sprite_hair, *re_sprite_body, *re_sprite_eyes;

With this clarification, each pointer is properly declared, resolving the compiler error and ensuring the intended functionality.