2005-06-02 wenzelm 2005-06-02 header;
2005-05-05 dixon 2005-05-05 lucas - made clean unify smash unifiers so that when we get flex-flex constraints subst does not barf. Also added fix_vars_upto_idx to IsaND.
2005-05-03 dixon 2005-05-03 lucas - improved interface to isand.ML and cleaned up clean-unification code, and added some better comments.
2005-04-22 dixon 2005-04-22 lucas - fixed a big with renaming of bound variables. Other small changes.
2005-04-21 berghofe 2005-04-21 Adapted to new interface of instantiation and unification / matching functions.
2005-03-03 skalberg 2005-03-03 Move towards standard functions.
2005-02-13 skalberg 2005-02-13 Deleted Library.option type.
2005-02-01 paulson 2005-02-01 the new subst tactic, by Lucas Dixon