Annoying PHP quirk.

SplInt.php

<?php

$integer = new \SplInt( 5 );

if( false === filter_var( $integer, FILTER_VALIDATE_INT, array( 'options' => array( 'min_range' => 1, 'max_range' => 9 ) ) ) )
{
    throw new \InvalidArgumentException( sprintf( 'An integer value of 1 through 9 is required, %s "%s" given.', gettype( $integer ), $integer ) );
}

// Result:
//   PHP Fatal error: Uncaught exception 'InvalidArgumentException' with message
//     'An integer value of 1 through 9 is required, object "5" given.' in /SplInt.php:7