Is there any key in php that can be used with an array without using isset check?

I have used a framework before, called speedPHP, which is rarely used by people. When using it, any key values ​​​​of these arrays such as session, get, post are not used isset, see I looked at its source code and didn’t see where it was set up. Recently, I thought this framework was slow, so I wrote a framework myself. I always have to isset when writing, especially when submitting a form. It can be written very quickly. Yes, I ended up writing for a long, long time, all while writing isset. So I want to ask if there is a way without writing isset? Also keep error reporting.

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Some people may say that this approach will screw me up in the end, but I have used that framework for more than a year, and I have never been screwed by the "no isset" thing...

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I woke up this morning and thought about it. I thought it had some kind of fault-tolerance settings. This morning I thought, maybe it was just the debug type that had been changed. Then I looked at its debug settings, and sure enough...

if( substr(PHP_VERSION, 0, 3) == "5.3" ){
    error_reporting(E_ALL & ~E_NOTICE & ~E_WARNING & ~E_DEPRECATED);
}else{
    error_reporting(E_ALL & ~E_NOTICE & ~E_WARNING);
}

speedPHP is written like this. After I copied these, sure enough, no errors were reported. It’s not that there were no errors, but no errors were reported.

Reply content:

I have used a framework before, called speedPHP, which is rarely used by people. When using it, any key values ​​​​of these arrays such as session, get, post are not used isset, see I looked at its source code and didn’t see where it was set up. Recently, I thought this framework was slow, so I wrote a framework myself. I always have to isset when writing, especially when submitting a form. It can be written very quickly. Yes, I ended up writing for a long, long time, all while writing isset. So I want to ask if there is a way without writing isset? Also keep error reporting.

---

Some people may say that this approach will screw me up in the end, but I have used that framework for more than a year, and I have never been screwed by the "no isset" thing...

---

I woke up this morning and thought about it. I thought it had some kind of fault-tolerance settings. This morning I thought, maybe it was just the debug type that had been changed. Then I looked at its debug settings, and sure enough...

if( substr(PHP_VERSION, 0, 3) == "5.3" ){
    error_reporting(E_ALL & ~E_NOTICE & ~E_WARNING & ~E_DEPRECATED);
}else{
    error_reporting(E_ALL & ~E_NOTICE & ~E_WARNING);
}

speedPHP is written like this. After I copied these, sure enough, no errors were reported. It’s not that there were no errors, but no errors were reported.