1. 04 Oct, 2017 2 commits
  2. 27 Sep, 2017 1 commit
  3. 26 Sep, 2017 2 commits
    • Robbert Krebbers's avatar
      aaa4f987
    • Robbert Krebbers's avatar
      Fix issue #98. · e17ac4ad
      Robbert Krebbers authored
      We used to normalize the goal, and then checked whether it was of
      a certain shape. Since `uPred_valid P` normalized to `True ⊢ P`,
      there was no way of making a distinction between the two, hence
      `True ⊢ P` was treated as `uPred_valid P`.
      
      In this commit, I use type classes to check whether the goal is of
      a certain shape. Since we declared `uPred_valid` as `Typeclasses
      Opaque`, we can now make a distinction between `True ⊢ P` and
      `uPred_valid P`.
      e17ac4ad
  4. 25 Sep, 2017 11 commits
  5. 21 Sep, 2017 2 commits
  6. 18 Sep, 2017 1 commit
  7. 17 Sep, 2017 3 commits
  8. 09 Sep, 2017 1 commit
  9. 28 Aug, 2017 2 commits
  10. 14 Jul, 2017 1 commit
  11. 27 Jun, 2017 1 commit
  12. 08 Jun, 2017 1 commit
  13. 06 Jun, 2017 1 commit
  14. 19 Apr, 2017 1 commit
  15. 24 Mar, 2017 3 commits
  16. 22 Mar, 2017 1 commit
  17. 14 Mar, 2017 3 commits
    • Robbert Krebbers's avatar
      Misc properties about languages. · 4e1bdcc7
      Robbert Krebbers authored
      4e1bdcc7
    • Robbert Krebbers's avatar
      Define `fill` in terms of a `foldl` over `fill_item`. · 6fc9c27e
      Robbert Krebbers authored
      This has some advantages:
      
      - Evaluation contexts behave like a proper "Huet's zipper", and thus:
        + We no longer need to reverse the list of evaluation context items in the
          `reshape_expr` tactic.
        + The `fill` function becomes tail-recursive.
      - It gives rise to more definitional equalities in simulation proofs using
        binary logical relations proofs.
      
        In the case of binary logical relations, we simulate an expressions in some
        ambient context, i.e. `fill K e`. Now, whenever we reshape `e` by turning it
        into `fill K' e'`, we end up with `fill K (fill K' e')`. In order to use the
        rules for the expression that is being simulated, we need to turn
        `fill K (fill K' e')` into `fill K'' e'` for some `K'`. In case of the old
        `foldr`-based approach, we had to rewrite using the lemma `fill_app` to
        achieve that. However, in case of the old `foldl`-based `fill`, we have that
        `fill K (fill K' e')` is definitionally equal to `fill (K' ++ K) e'` provided
        that `K'` consists of a bunch of `cons`es (which is always the case, since we
        obtained `K'` by reshaping `e`).
      
      Note that this change hardly affected `heap_lang`. Only the proof of
      `atomic_correct` broke. I fixed this by proving a more general lemma
      `ectxi_language_atomic` about `ectxi`-languages, which should have been there
      in the first place.
      6fc9c27e
    • Robbert Krebbers's avatar
  18. 09 Mar, 2017 1 commit
  19. 14 Feb, 2017 1 commit
  20. 06 Feb, 2017 1 commit