is_attachment() WordPress Function

function is_attachment( $attachment = '' ) {
	global $wp_query;

	if ( ! isset( $wp_query ) ) {
		_doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1.0' );
		return false;
	}

	return $wp_query->is_attachment( $attachment );
}
Uses	Description
wp-includes/l10n.php:__()	Retrieve the translation of $text.
wp-includes/class-wp-query.php:WP_Query::is_attachment()	Is the query for an existing attachment page?
wp-includes/functions.php:_doing_it_wrong()	Mark something as being incorrectly called.
Used By	Description
wp-includes/embed.php:wp_embed_excerpt_attachment()	Filters the post excerpt for the embed template.
wp-includes/link-template.php:get_adjacent_post_link()	Retrieves the adjacent post link.
wp-includes/link-template.php:get_adjacent_post_rel_link()	Retrieves the adjacent post relational link.
wp-includes/link-template.php:adjacent_posts_rel_link_wp_head()	Displays relational links for the posts adjacent to the current post for single post pages.
wp-includes/link-template.php:get_boundary_post()	Retrieves the boundary post.
wp-includes/post-template.php:wp_list_pages()	Retrieves or displays a list of pages (or hierarchical post type items) in list (li) format.
wp-includes/post-template.php:get_post_class()	Retrieves an array of the class names for the post container element.
wp-includes/post-template.php:get_body_class()	Retrieves an array of the class names for the body element.
wp-includes/canonical.php:redirect_canonical()	Redirects incoming links to the proper URL based on the site url.