Hi there has anybody experimented with the implementation in R of linear lists, as described e.g. in books on Pascal (Jensen and Wirth), or Wirth, "Algorithms and data structures" ? See \url{www.dbnet.ece.ntua.gr/~adamo/csbooksonline/AD.pdf } Pointers would be welcome. Christian -- -- Christian W. Hoffmann, Rigiblickstrasse 15 b, CH-8915Hausen am Albis, Switzerland, Tel +41-44-7640853, c-w.hoffmann at sunrise.ch