PHP Require conditional reference issues

On the internet to see such a message
The Include () function is the same as require (), but there are some differences in usage, include () is a conditional include function, and require () is an unconditional include function.
Regardless of the $something value, the following code will include the file somefile.php in the file:

if ($something) {require ' somefile.php ';}

But in my actual test, the conditions are not included when the condition is false.

Because the environment is different, or there is another reason, please advise us

Reply to discussion (solution)

What you see is an introduction to PHP4.
In php5, both require and include are loaded at precompiled time (invisible when not in use)
The difference between the two is limited to the former when an error breaks the program, and the latter does not

This is obviously wrong, at least in the current version, if (false) {} will not execute the IF code block at all.

$something = 0 or equal to null look, you're going to introduce it.

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