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do_action( "hook_name" )apply_filters( "hook_name", "what_to_filter" ).Remember, this hook may occur in more than one file. Moreover, the hook's context may change from version to version.
This hook occurs 2 times in this file.
| Line | Code | 
|---|---|
| 1322 |      } | 
| 1323 |  | 
| 1324 |      /** | 
| 1325 |       * Filter the list of blacklisted usernames. | 
| 1326 |       * | 
| 1327 |       * @since 4.4.0 | 
| 1328 |       * | 
| 1329 |       * @param array $usernames Array of blacklisted usernames. | 
| 1330 |       */ | 
| 1331 |      $illegal_logins = (array) apply_filters( 'illegal_user_logins', array() ); | 
| 1332 |  | 
| 1333 |      if ( in_array( strtolower( $user_login ), array_map( 'strtolower', $illegal_logins ) ) ) { | 
| 1334 |           return new WP_Error( 'invalid_username', __( 'Sorry, that username is not allowed.' ) ); | 
| 1335 |      } | 
| 1336 |  | 
| 1337 |      /* | 
| 1338 |       * If a nicename is provided, remove unsafe user characters before using it. | 
| 1339 |       * Otherwise build a nicename from the user_login. | 
| 1340 |       */ | 
| Line | Code | 
| 2121 |           $errors->add( 'empty_username', __( '<strong>ERROR</strong>: Please enter a username.' ) ); | 
| 2122 |      } elseif ( ! validate_username( $user_login ) ) { | 
| 2123 |           $errors->add( 'invalid_username', __( '<strong>ERROR</strong>: This username is invalid because it uses illegal characters. Please enter a valid username.' ) ); | 
| 2124 |           $sanitized_user_login = ''; | 
| 2125 |      } elseif ( username_exists( $sanitized_user_login ) ) { | 
| 2126 |           $errors->add( 'username_exists', __( '<strong>ERROR</strong>: This username is already registered. Please choose another one.' ) ); | 
| 2127 |  | 
| 2128 |      } else { | 
| 2129 |           /** This filter is documented in wp-includes/user.php */ | 
| 2130 |           $illegal_user_logins = array_map( 'strtolower', (array) apply_filters( 'illegal_user_logins', array() ) ); | 
| 2131 |           if ( in_array( strtolower( $sanitized_user_login ), $illegal_user_logins ) ) { | 
| 2132 |                $errors->add( 'invalid_username', __( '<strong>ERROR</strong>: Sorry, that username is not allowed.' ) ); | 
| 2133 |           } | 
| 2134 |      } | 
| 2135 |  | 
| 2136 |      // Check the email address | 
| 2137 |      if ( $user_email == '' ) { | 
| 2138 |           $errors->add( 'empty_email', __( '<strong>ERROR</strong>: Please type your email address.' ) ); | 
| 2139 |      } elseif ( ! is_email( $user_email ) ) { |