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filter is not described

wp_insert_post_empty_content filter-hook . WP 3.3.0

Filters whether the post should be considered "empty".

The post is considered "empty" if both:

  1. The post type supports the title, editor, and excerpt fields
  2. The title, editor, and excerpt fields are all empty

Returning a truthy value to the filter will effectively short-circuit the new post being inserted, returning 0. If $wp_error is true, a WP_Error will be returned instead.

Usage

add_filter( 'wp_insert_post_empty_content', 'filter_function_name_4395', 10, 2 );
function filter_function_name_4395( $maybe_empty, $postarr ){
	// filter...

	return $maybe_empty;
}
$maybe_empty(true/false)
Whether the post should be considered "empty".
$postarr(array)
Array of post data.

Where the hook is called

wp_insert_post()
wp_insert_post_empty_content
wp-includes/post.php 3292
if ( apply_filters( 'wp_insert_post_empty_content', $maybe_empty, $postarr ) ) {

Where the hook is used (in WP core)

wp-includes/class-wp-customize-nav-menus.php 831
add_filter( 'wp_insert_post_empty_content', '__return_false', 1000 );
wp-includes/class-wp-customize-nav-menus.php 833
remove_filter( 'wp_insert_post_empty_content', '__return_false', 1000 );