Error Suppression Operator (@) as a shortcut for isset(). Bad Practice? [closed]
if ( isset($_SESSION) && isset($_SESSION['myVariable']) && $_SESSION['myVariable'] == true )
  echo "myVariable is True!";

if ( @$_SESSION['myVariable'] == true )
  echo "myVariable is True!";

session_start();
$count = 0;
$start = microtime(true);

for($i=0;$i<10000;$i++){
    if ( @$_SESSION['myVariable'] == true ){
      $count++;
    }
}
echo "Took ".(microtime(true)-$start)." Microseconds with error supression.<br />";

$count = 0;
$start = microtime(true);
for($i=0;$i<10000;$i++){
    if ( isset($_SESSION) && isset($_SESSION['myVariable']) && $_SESSION['myVariable'] == true ){
      $count++;
    }
}
echo "Took ".(microtime(true)-$start)." Microseconds with formal checks.<br />";

Took 0.010571002960205 Microseconds with error supression.
Took 0.002446174621582 Microseconds with formal checks.

Took 0.0098469257354736 Microseconds with error supression.
Took 0.00094795227050781 Microseconds with formal checks.

if (!@chmod($someFileUri)) {
    throw new Exception('Cannot change mode plus some extra stuff...');
}