I need help about php version.

First, thank you for CI4 development team.

I have a question.
- Why CI4 must require php 7.1 or above version, not 7.0 ?

So, I saw index.php file. 
there are the folling part.

$minPHPVersion = '7.1';

If I just change this to '7.0' then, can I use CI4 in php 7.0 version environment. No problem?
please help me.

I can't find the issue reference from GitHub right now, but there was a framework loading issue that needed PHP 7.1, so no, PHP 7.0 will not work properly.

7.1 introduce nullable types, void return type and catching of multiple exception types
-> so you could remove all parameter and function types and use it with 7.0

but the types gives strong guarantee which makes finding of errors much easier and the code overall more stable

7.1 introduce nullable types, void return type and catching of multiple exception types
-> so you could remove all parameter and function types and use it with 7.0

but the types gives strong guarantee which makes finding of errors much easier and the code overall more stable

Thank you for your advice. Perhaps there is not another problem.
I also checked it through PhpStorm inspection feature (php version 7.0).
So I think that maybe I could CI4 in php 7.0.

PHP 7 only has 23 days of security only fixes until it's considered EOL. A better option would be to see if you can get your PHP version upgraded, either locally or on your server.

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