变量可以作为方法名吗？该怎么处理

$name="hello()";
$this->$name;
function hello(){
echo "hello word";
}

$name="hello";
$name();
function hello(){
echo "hello word";
}

------解决方案--------------------
$name="hello()";
eval("return $name;");

function hello(){
echo "hello word";
}