Changes by: Xin Yu (xiny at cs.caltech.edu)
Date: 2005-12-21 00:02:26 -0800 (Wed, 21 Dec 2005)
Revision: 8337
Log message:

      Added foldClose2C in Itt_Struct2, and using it reproved
      Itt_hoas_debruijn.reduce_vec_bind_of_mk_bterm_of_list_of_fun.