/*
 * @(#)$Id: length,v 1.1 1994/09/16 09:37:56 dream Exp $
 *
 * $Log: length,v $
 * Revision 1.1  1994/09/16 09:37:56  dream
 * Initial revision
 *
 */

length(r)<==>list_ind(r,0,[~,~,v,s(v)]).
