disabled Thm.compress (again) -- costs for building tables tend to be higher than potential benefit;

entity markup for bound variables;

merged

made SML/NJ happy

adding some documentation about the values command to the isar reference

adding a minimal documentation about the code_pred command to the isar reference

more specific treatment of defines/assumes -- avoid normalizing defs by themselves (NB: locale specifications and Local_Theory.define may lead to arbitrary mixture);