${!${''} = 你的代码块}
var_dump(${!${''} = implode('、', ['apple', 'banana'])});
$fruits = implode('、', ['apple', 'banana']);
var_dump("fruits: $fruits.");
var_dump("fruits: implode('、', ['apple', 'banana']).");
var_dump("fruits: ${!${''} = implode('、', ['apple', 'banana'])}.");
// string(23) "fruits: apple、banana."
// string(44) "fruits: implode('、', ['apple', 'banana'])."
// string(23) "fruits: apple、banana."