 25 Oct, 2016 2 commits


Robbert Krebbers authored

Robbert Krebbers authored
There are now two proof mode tactics for dealing with modalities:  `iModIntro` : introduction of a modality  `iMod pm_trm as (x1 ... xn) "ipat"` : eliminate a modality The behavior of these tactics can be controlled by instances of the `IntroModal` and `ElimModal` type class. We have declared instances for later, except 0, basic updates and fancy updates. The tactic `iMod` is flexible enough that it can also eliminate an updates around a weakest pre, and so forth. The corresponding introduction patterns of these tactics are `!>` and `>`. These tactics replace the tactics `iUpdIntro`, `iUpd` and `iTimeless`. Source of backwards incompatability: the introduction pattern `!>` is used for introduction of arbitrary modalities. It used to introduce laters by stripping of a later of each hypotheses.

 05 Oct, 2016 1 commit


Robbert Krebbers authored

 19 Sep, 2016 1 commit


Robbert Krebbers authored
This closes issue 32.

 09 Sep, 2016 1 commit


Robbert Krebbers authored
Before this commit, given "HP" : P and "H" : P ★ Q with Q persistent, one could write: iSpecialize ("H" with "#HP") to eliminate the wand in "H" while keeping the resource "HP". The lemma: own_valid : own γ x ⊢ ✓ x was the prototypical example where this pattern (using the #) was used. However, the pattern was too limited. For example, given "H" : P₁ ★ P₂ ★ Q", one could not write iSpecialize ("H" with "#HP₁") because P₂ ★ Q is not persistent, even when Q is. So, instead, this commit introduces the following tactic: iSpecialize pm_trm as # which allows one to eliminate implications and wands while being able to use all hypotheses to prove the premises, as well as being able to use all hypotheses to prove the resulting goal. In the case of iDestruct, we now check whether all branches of the introduction pattern start with an `#` (moving the hypothesis to the persistent context) or `%` (moving the hypothesis to the pure Coq context). If this is the case, we allow one to use all hypotheses for proving the premises, as well as for proving the resulting goal.

 24 Aug, 2016 1 commit


Robbert Krebbers authored
This is allowed as long as one of the conjuncts is thrown away (i.e. is a wildcard _ in the introduction pattern). It corresponds to the principle of "external choice" in linear logic.

 05 Aug, 2016 2 commits


Robbert Krebbers authored
Also make those for introduction and elimination more symmetric: !% pure introduction % pure elimination !# always introduction # always elimination !> later introduction > pat timeless later elimination !==> view shift introduction ==> pat view shift elimination

Robbert Krebbers authored
This commit features:  A simpler model. The recursive domain equation no longer involves a triple containing invariants, physical state and ghost state, but just ghost state. Invariants and physical state are encoded using (higherorder) ghost state.  (Primitive) view shifts are formalized in the logic and all properties about it are proven in the logic instead of the model. Instead, the core logic features only a notion of raw view shifts which internalizing performing frame preserving updates.  A better behaved notion of mask changing view shifts. In particular, we no longer have sideconditions on transitivity of view shifts, and we have a rule for introduction of mask changing view shifts ={E1,E2}=> P with E2 ⊆ E1 which allows to postpone performing a view shift.  The weakest precondition connective is formalized in the logic using Banach's fixpoint. All properties about the connective are proven in the logic instead of directly in the model.  Adequacy is proven in the logic and uses a primitive form of adequacy for uPred that only involves raw views shifts and laters. Some remarks:  I have removed binary view shifts. I did not see a way to describe all rules of the new mask changing view shifts using those.  There is no longer the need for the notion of "frame shifting assertions" and these are thus removed. The rules for Hoare triples are thus also stated in terms of primitive view shifts. TODO:  Maybe rename primitive view shift into something more sensible  Figure out a way to deal with closed proofs (see the commented out stuff in tests/heap_lang and tests/barrier_client).

 27 Jul, 2016 1 commit


Robbert Krebbers authored
This reverts commit c43eb936. The hack using class_apply has some strange behaviors, see: https://sympa.inria.fr/sympa/arc/coqclub/201607/msg00094.html

 26 Jul, 2016 1 commit


Robbert Krebbers authored

 13 Jul, 2016 1 commit


Robbert Krebbers authored
The intropattern {H} also meant clear (both in ssreflect, and the logic part of the introduction pattern).

 30 Jun, 2016 3 commits


Robbert Krebbers authored
For example iIntros "{$H1 H2} H1" frames H1, clears H2, and introduces H1.

Robbert Krebbers authored
This fixes a bug in 916ff44a causing proof mode notations not being pretty printed.

Robbert Krebbers authored
This tweak allows us to declare pvs as an instance of FromPure (it is not an instance of IntoPure), making some tactics (like iPureIntro and done) work with pvs too.

 17 Jun, 2016 1 commit


Robbert Krebbers authored

 01 Jun, 2016 1 commit


Robbert Krebbers authored
We used => before, which is strange, because it has another meaning in ssreflect.

 31 May, 2016 2 commits


Robbert Krebbers authored
be the same as
↔ . This is a fairly intrusive change, but at least makes notations more consistent, and often shorter because fewer parentheses are needed. Note that viewshifts already had the same precedence as →. 
Robbert Krebbers authored
It used to be: (P ={E}=> Q) := (True ⊢ (P → ={E}=> Q)) Now it is: (P ={E}=> Q) := (P ⊢ ={E}=> Q)

 30 May, 2016 1 commit


Robbert Krebbers authored

 27 May, 2016 1 commit


Robbert Krebbers authored

 24 May, 2016 3 commits


Robbert Krebbers authored
To do so, we have introduced the specialization patterns: =>[H1 .. Hn] and =>[H1 .. Hn] That generate a goal in which the view shift is preserved. These specialization patterns can also be used for e.g. iApply. Note that this machinery is not tied to primitive view shifts, and works for various kinds of goal (as captured by the ToAssert type class, which describes how to transform the asserted goal based on the main goal). TODO: change the name of these specialization patterns to reflect this generality.

Robbert Krebbers authored

Robbert Krebbers authored
Changes:  We no longer have a different syntax for specializing a term H : P ★ Q whose range P or domain Q is persistent. There is just one syntax, and the system automatically determines whether either P or Q is persistent.  While specializing a term, always modalities are automatically stripped. This gets rid of the specialization pattern !.  Make the syntax of specialization patterns more consistent. The syntax for generating a goal is [goal_spec] where goal_spec is one of the following: H1 .. Hn : generate a goal using hypotheses H1 .. Hn H1 .. Hn : generate a goal using all hypotheses but H1 .. Hn # : generate a goal for the premise in which all hypotheses can be used. This is only allowed when specializing H : P ★ Q where either P or Q is persistent. % : generate a goal for a pure premise.

 21 May, 2016 1 commit


Ralf Jung authored

 06 May, 2016 1 commit


Robbert Krebbers authored

 02 May, 2016 3 commits


Robbert Krebbers authored

Robbert Krebbers authored

Robbert Krebbers authored
iSpecialize and iDestruct. These tactics now all take an iTrm, which is a tuple consisting of a.) a lemma or name of a hypotheses b.) arguments to instantiate c.) a specialization pattern.

 27 Apr, 2016 1 commit


Robbert Krebbers authored

 25 Apr, 2016 1 commit


Robbert Krebbers authored

 20 Apr, 2016 2 commits


Robbert Krebbers authored

Robbert Krebbers authored
 It can now also frame under later.  Better treatment of evars, it now won't end up in loops whenever the goal involves subformulas ?P and it trying to apply all framing rules eagerly.  It no longer delta expands while framing.  Better clean up of True subformulas after a successful frame. For example, framing "P" in "▷ ▷ P ★ Q" yields just "Q" instead of "▷ True ★ Q" or so.

 11 Apr, 2016 1 commit


Robbert Krebbers authored
