CLearnLessonTree::EnsureStrictlyCastableToInt

protected function EnsureStrictlyCastableToInt ($i)
{
	if ( ( ! is_numeric($i) )
		|| ( ! is_int($i + 0) )
	)
	{
		throw new LearnException ('Non-strictly casts to integer: ' . htmlspecialcharsbx($i), 
			LearnException::EXC_ERR_ALL_PARAMS 
			| LearnException::EXC_ERR_ALL_LOGIC);
	}
}