Get error before they execute the error message function - php

Question

I want to receive the error message in php before it gets executed. Basicly what i mean is that if I would have a bad code:
// This code is incorrect, I want to receive the error before it gets handled!
$some_var = new this_class_is_not_made;
Now that class does not exist, so it would be handles by the default error handler in php. But I want to disable the normal error handler and create my own.
Another example:
somefunction( string some_var ); // some_var misses the variable prefix. ( $ )
Example error message:
Fatal error: function 'some_var' is not defined in line: $x!
And this error would be: somefunction( string some_var );
But how would I receive the messages but also disable the normal error system?
EDIT: Making the error system execute a user-defined function
// I would want the error system to execute a function like this:
function(string $errorMessage, int $error_code){
if($error_code < 253){ return "Fatal error"; }
if($error_code < 528 && $error_code > 253){ return "Warning"; }
}
Answer found: By: ShiraNai7
try
{
// Code that may throw an Exception or Error.
}
catch (Throwable $t)
{
// Executed only in PHP 7, will not match in PHP 5
}
catch (Exception $e)
{
// Executed only in PHP 5, will not be reached in PHP 7
}

Answer 1

In PHP 7.0.0 or newer the code will throw Error exception if this_class_is_not_made doesn't exist.
try {
$some_var = new this_class_is_not_made;
} catch (Error $e) {
echo $e->getMessage();
}
Note that that this will also catch any other Error exceptions in case this_class_is_not_made does exist and causes some other error along the way.
In PHP versions prior to 7.0.0 you're out of luck - fatal errors always terminate the main script.
It might be a better idea to use class_exists() instead:
if (class_exists('this_class_is_not_made')) {
$some_var = new this_class_is_not_made;
}
This works in all PHP versions that support classes.