function enqueue_assets() {
		if (!is_singular()) {
			return;
		}

		$content = get_post_field('post_content', get_the_ID());
		if (!has_shortcode($content, 'shortcode_name_here')) {
			return;
		}

		wp_enqueue_script('contact_js', get_template_directory_uri() . '/assets/js/contact.js', array(), '1.1', true);
}

add_action('wp_enqueue_scripts', 'enqueue_assets');