static variables in traits

[stijn0713]

From the manual: "Static variables can be referred to in trait methods, but cannot be defined by the trait. Traits can, however, define static methods for the exhibiting class."

 

trait Counter {
    public function inc() {
        static $c = 0;
        $c = $c + 1;
        echo "$c\n";
    }
}

 

Static variables always have to be defined in methods if i'm right, and considering that the above example works perfectly, i don't see what would be a problem to work with static variables in traits.

 

 

So my question is:

 

What is meant with "but cannot be defined by the trait"?

 

 

[trq]

 

Static variables always have to be defined in methods if i'm right

 

That is incorrect. You can define a static property like any other.

[requinix]

Meaning defined at the class (trait) level. Defining them in methods is fine.

trait Counter {

	private static $c = 0;

	public function inc() {

		$this->c++;

		echo $this->c, "\n";

	}

}