ArgumentCountError

ArgumentCountError is thrown when too few arguments are passed to a user-defined function or method. This is an error, not an exception.

No exception is raised for extra parameters, as those may still be processed by the method itself.

<?php

function foo($a) {}

// No error is raised here
foo(1,2);

// ArgumentCountError is catchable
try {
    foo();
} catch (ArgumentCountError) {
    print 'No enough parameters passed.';
}
?>

Documentation

Related : throw, Try-catch