What will be the output of the following PHP code?

interface Exp { public function x();}

class First implements Exp {

public function x() {}

}

class Second {}

function x(Exp $e){

echo get_class($e)."\n";

}

x(new First);

x(new Second);

?>

Which is the correct syntax for a function with iterable generator return type?

Under which scenario, a TypeError may be thrown? i) When the argument type, which is being passed to a function, does not match its corresponding declared parameter type. ii) When the returned value from a function does not match the declared function return type. iii) When an invalid number of arguments are passed to a built-in PHP function.

Find the output of the following PHP code. $string = echo 'The output for '$string' is '$string[-1]'.\n'; ?>

While creating or modifying an array in PHP 7.1, what will happen if an empty index operator is applied on a string?

(8 < 1 || 4 >= 4 ) will return

A fatal error would be caught by

Which function would you use to append one or more elements to the end of the array?

One can include ('abc.PHP') two times in a PHP page 'makeit.PHP'.

If regular expressions must be used, in general which type of regular expression functions available to PHP is preferred for performance reasons?