Common techniques for error handling in PHP

function error_reg(){
 $ar=array(
  E_ERROR => 'error',
  E_WARNING => 'warning',
  E_PARSE =>'prase',
  E_NOTICE => 'notice'
 );
 register_shutdown_function(function() use ($ar){
  $ers=error_get_last();
  if($ers['type']!=8 && $ers['type']){
   $er=$ar[$ers['type']].$ers['type'].': '.' '.$ers['message'].' => '.$ers['file'].' line:'.$ers['line'].' '.date('Y-m-d H:i:s')."\n";
   error_log($er,3,'/tmp/php_error.log');
  }
 });
 set_error_handler(function($a,$b,$c,$d) use ($ar){
  if($a!=8 && $a){
   $er=$ar[$a].$a.': '.$b.' => '.$c.' line:'.$d.' '.date('Y-m-d H:i:s')."\n";
   error_log($er,3,'/tmp/php_error.log');
  }
 },E_ALL ^ E_NOTICE);
}