PHP5.5empty + trick variable pitfalls

PHP5.5empty + Magic variable pitfalls today when I was testing the code, I encountered such a question? Dump (int) empty ($ response-& gt; raw_body); $ response_body $ response-& gt; raw_body; dump (. (int) empty ($ response_body) PHP 5.5 empty + Magic variable pitfalls

Why do I have such a question during code testing today?

dump((int)empty($response->raw_body));$response_body = $response->raw_body;dump(' ' . (int)empty($response_body));

? The output result of this code is:

Write

1
0

?

Why? it's strange, isn't it? My $ response is a class object, which gets

raw_body

Properties are obtained through magic functions.

public function __get($property){echo 123;if (property_exists($this, $property)) {return $this->$property;}}

?

For testing, I output 123 in the above code and the result is displayed.

Write

1

123

0

?

That is to say

(int)empty($response->raw_body)

The _ get method of the $ response object is not executed.

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So when using PHP magic variables, you should pay attention to this pitfall.

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