PHP Late Static Binding - 解析错误:语法错误,意外T_STRING,期待T_VARIABLE

Question

测试一些后期静态绑定并在第5行获取此错误:

Parse error: syntax error, unexpected T_STRING, expecting T_VARIABLE

第5行:

protected static test = 'A TEST';

这是来源:

class A {

    protected static test = 'A TEST';

    public static function test() {
        echo $this->test;
    }
}

Class B extends A {
    public static test = "B TEST";
    public function static_test() {
        echo static::$test;
    }
}

$a = new A;
$b = new B;

echo '$a->test()<br />';
echo $a->test();
echo '<br /> <br />';
echo '$b->test()<br />';
echo $b->test();
echo '<br /> <br />';
echo '$b->static_test()<br />';
echo $b->static_test();

可以说我很难过.

Answer 1

protected static $test = 'A TEST';
                 ^--- !!!

这不是常数 - 所以它应该以$符号开头