Source Reference:

• Component: bbPress :: bbp-core

  File: /bbp-includes/bbp-common-template.php :: Trac Source Line: 334

  function bbp_is_reply( $post_id = 0 ) {
  
  	// Assume false
  	$retval = false;
  
  	// Supplied ID is a reply
  	if ( !empty( $post_id ) && ( bbp_get_reply_post_type() == get_post_type( $post_id ) ) )
  		$retval = true;
  
  	return (bool) apply_filters( 'bbp_is_reply', $retval, $post_id );
  }
  
  /**
   * Check if current page is a reply edit page
   *
   * @since bbPress (r2753)
   *
   * @uses WP_Query Checks if WP_Query::bbp_is_reply_edit is true
   * @return bool True if it's the reply edit page, false if not
   */