Description:
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It would be useful if trigger_error would accept custom error types.  Although I can do this with Exceptions, I can't see a way of sending variable context from where an exception is thrown to the exception handler, and loosing variable context would be a deal breaker.


Reproduce code:
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define('E_CUSTOM_1', -1);
define('E_CUSTOM_2', -2);
function error_handler ($errno, $errmsg, $scriptname, $scriptline, $errcontext) {
   if ($errno == E_CUSTOM_1) die('custom error type');
}
set_error_handler('error_handler');
trigger_user('message', E_CUSTOM_1);


Expected result:
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custom error type


Actual result:
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PHP Warning:  Invalid error type specified in - on line 7