Changes of Refinement Framework since 2011-12-24:

2014-06 Peter Lammich
  * Added vc_solve method
  * Fine-tuned rcg/vcg setup for ASSERT/ASSUME
  * Added more convenience lemmas
  * VCG-rules for nfoldli
  * Improved Autoref-setup for FOREACH-loops

2013-09 Peter Lammich
  * Made this dependent on Automatic_Refinement

2012-11-30 Peter Lammich
  * Added eq_assume_tac to Refine.post_tac

2012-11-06 Peter Lammich
  * Added knowledge that invar holds for initial state to WHILE refinement rules

2012-10-05 Peter Lammich
  * New autoref framework. MAJOR INCOMPATIBILITY
    The new framework, although a prototype, is aimed at producing reasonable
    translations with as few required configuration as possible. See examples
    in ex/ directory for usage.
  * Definitions of relators are now in lemm collection refine_rel_defs.
    No longer in refine_hsimp. INCOMPATIBILITY

2012-08-31 Peter Lammich
  * Adaptions to new ICF v2
  * Stronger REC/RECT rules: 
  * Added abbreviations xx.R == br \alpha invar to ICF interfaces

2012-07-10 Peter Lammich
  * Maintenance changes
  * Added fo_rule - method that applies theorems using first-order matching.
    Works particular well with arg_cong, fun_cong.
  * Removed definitions of standard relation combinators 
    (rprod, map_set_rel, etc.) from standard simpset. They are now all in the
    theorems collection refine_rel_defs. INCOMPATIBILITY: Add refine_rel_defs
    to the simpset, but first try whether adding refine_hsimp does the job.
  * Introduced ropt relation combinator, and changed setup for autoref_ex. 
    Maybe INCOMPATIBILITY.

2012-07-02 Peter Lammich
  * Changed map_set_rel to pose additional invariant on concrete set: All 
    elements must actually be mapped.
  * Added nested-DFS algorithm with witness generation as example. The algorithm
    uses the RECT-combinator to implement a nested DFS search for an accepting
    cycle in a Buechi-automaton. It is a quite complex example that 
    demonstrates how to use the RECT-combinators and automatic refinement.

2012-06-25 Peter Lammich
  * WHILExx_refine_genR and FOREACHxxx_refine_genR rules that allow to exploit
    that the condition does not hold when the loop terminates.
  * Changes imported from Neumann's Refine_Addition theory:
      - Added REC(T)_rule_arbN for N=2,3
      - Added bind2letRETURN_refine rules as [refine2], to account for pattern
        RETURN (Let _ _) <= \<Down> R bind _ _

2012-06-21 Peter Lammich
  * Fine-tuned standard refinement setup: intro_spec_refine and bind_refine_RES
    MAYBE INCOMPATIBILITY, but in most cases it should just do the right thing.
  * Improved concrete_definition command. Now also exports a lemma 
    name.refine.
  * Added prepare_code_thms command, that processes a set of definition 
    theorems, and declares code lemmas, handling recursion combinators.

2012-06-18 Peter Lammich
  * Added first version of concrete_definition command, that saves the user
    from copy-pasting when making definitions out of refinement theorems.
    See userguide for an example. 
    INCOMPATIBILITY: In order to make the new command work under ProofGeneral,
    you need to copy the keyword file Libs/Refine_Monadic/isar-keywords.el to
    some appropriate directory, e.g. ~/.isabelle/etc

2012-06-12 Peter Lammich:
  * Bugfix: FOREACHc_rule was to weak (probably a typo).
  * Added alternative FOREACH??i_rule', that allow for less redundant proofs
    in some cases.
  * Added support for option_case.
  * More general proof rules for recursion combinator:
    RECT_rule_arb and REC_rule_arb now allow for generalizing over variables
    that occur in the specification, but not in the program.
  * Improved rprems_tac such that it can cope with schematic type variables.
    Now refine_autoref works with REC-combinators more cleanly.

2012-04-23 Thomas Tuerk: Ordered FOREACH.

2012-03-20 Thomas Tuerk: Adaption to changed iterator interface in Collection Framework

2012-02-21
  * Declared RETURN_SPEC_refine_sv as standard [refine]-rule.
    Potential INCOMPATIBILITY.

2012-02-20
  * Modified automatic refinement: Using Method.assm_tac to discharge
    by assumption. Potential INCOMPATIBILITY, but should be limited to very
    rare cases, where one tried to work around the non-discharged assumption.

2012-01-28
  * Added parameters to refine_transfer, refine_rcg, and refine_autoref.
    Usage:
      refine_transfer trans_thms
      refine_rcg refine_thms
      refine_autoref spec_thms
  * "refine_dref_type_only" is now "refine_dref_type (nopost)". INCOMPATIBILITY.
  * Added "refine_dref_type (trace)"
  * "refine_autoref_ss" is now "refine_autoref (trace) (ss)". INCOMPATIBILITY.
  * Changed determinization for iterators. An additional wrapper-function 
    occurs in generated function. INCOMPATIBILITY if generated function was copied.
  


2012-01-26
  * Added monotonicity prover (refine_mono - method), and integrated it
    with refine_rcg tactic. Maybe INCOMPATIBILITY, however, it only changes
    mono-goals that it can completely solve.
  * Automatic Refinement. Examples are in: 
      (ex/Automatic_Determinization, ex/Recursion, 
       ../Dijkstra/Dijkstra_Impl_Aref).
  * Example for use of REC and RECT combinators (ex/Recursion)

2012-01-16 [Release to Cava-Repo]
  * Changed definition of conc_fun (\Down), such that \Up and \Down always form
    a Galois-Connection. Equivalent in the single valued case, INCOMPATIBILITY
    in the non-single-valued case. Currently, refinement rules for WHILE assume 
    singe-valued relations, thus had to disable WHILEI_invisible_refine example.
    Generalizing to general case remains future work.
  * Total correct recursion is now expressed by greatest fixed points rather than
    least fixed points with asserted variant. Rules remain the same for 
    WHILE-loops, INCOMPATIBILITY for arbitrary recursion. 
    Introduced REC and RECT combinators, that should be used for recursion 
    (formerly lfp and lfpT). 
  * Changed code generation. INCOMPATIBILITY. Partial correct code now is inside 
    a monad with a flat complete lattice domain, rather than the option monad.
    The embedding function is nres_of (formerly: EMBED).
    The actual translation is done by the refine_transfer method 
    (formerly: (rule refine_cgt / refine_cgp)+), that handles both, goals of the
    form "RETURN ?f <= S" and "nres_of ?f <= S"
    Also the attribute names changed: [refine_cgp] and [refine_cgt] are both
    [refine_transfer] now. 

2011-12-31
  * Added WHILEI_invisible_refine rule, that supports refinement with invisible
    concrete steps for partial correct WHILE-loops. Also added example to ex/ 
    subdirectory.
  * Fixed bind2let_refine rule, the assumption was to strong.
  * Renamed le_ASSERTI_pres -> ref_ASSERTI_pres

2011-12-30:
  * Added FOREACH-refine rules with stronger coupling invariants.
  * Added conditions to step-refine assumptions of conditional foreach rules.

2011-12-29:
  * Added nofail/inres predicates and related lemmas.
  * Arbitrary recursion via lfp. Changed basis of while-combinator to
    use that. Also a well-founded variant lfpT. 
    INCOMPATIBILITIES:
      WINV is now WI_reach, and definition of while-loop has changed completely.
  


