 22 Nov, 2016 2 commits


Robbert Krebbers authored
We do this by introducing a type class UpClose with notation ↑. The reason for this change is as follows: since `nclose : namespace → coPset` is declared as a coercion, the notation `nclose N ⊆ E` was pretty printed as `N ⊆ E`. However, `N ⊆ E` could not be typechecked because type checking goes from left to right, and as such would look for an instance `SubsetEq namespace`, which causes the right hand side to be illtyped.

Ralf Jung authored

 03 Nov, 2016 1 commit


Robbert Krebbers authored
The old choice for ★ was a arbitrary: the precedence of the ASCII asterisk * was fixed at a wrong level in Coq, so we had to pick another symbol. The ★ was a random choice from a unicode chart. The new symbol ∗ (as proposed by David Swasey) corresponds better to conventional practise and matches the symbol we use on paper.

 01 Nov, 2016 3 commits
 28 Oct, 2016 2 commits


Robbert Krebbers authored

Ralf Jung authored

 27 Oct, 2016 2 commits
 25 Oct, 2016 4 commits


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.

Robbert Krebbers authored

Robbert Krebbers authored

Robbert Krebbers authored
And also rename the corresponding proof mode tactics.

 06 Sep, 2016 1 commit


Robbert Krebbers authored

 25 Aug, 2016 1 commit


Robbert Krebbers authored
NB: these scopes delimiters were already there before Janno's a0067662.

 09 Aug, 2016 1 commit


Ralf Jung authored

 08 Aug, 2016 1 commit


Robbert Krebbers authored
This makes stuff more uniform and also removes the need for the [inGFs] type class. Instead, there is now a type class [subG Σ1 Σ2] which expresses that a list of functors [Σ1] is contained in [Σ2].

 05 Aug, 2016 4 commits


Robbert Krebbers authored
This better reflects the name of the bind rule. I renamed an internal tactic that was previously called wp_bind into wp_bind_core.

Robbert Krebbers authored

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).

 04 Aug, 2016 1 commit


Robbert Krebbers authored
It not behaves more consistently with iExact and thus also works in the case H : P ★ □^n Q  Q.

 27 Jul, 2016 2 commits


Robbert Krebbers authored
This reverts commit 20b4ae55, which does not seem to work with Coq 8.5pl2 (I accidentally tested with 8.5pl1).

Robbert Krebbers authored
This makes type checking more directed, and somewhat more predictable. On the downside, it makes it impossible to declare the singleton on lists as an instance of SingletonM and the insert and alter operations on functions as instances of Alter and Insert. However, these were not used often anyway.

 19 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 1 commit


Robbert Krebbers authored
Concretely, when execution of any of the wp_ tactics does not yield another wp, it will make sure that a view shift is kept. This behavior was already partially there, but now it is hopefully more consistent.

 16 Jun, 2016 1 commit


Robbert Krebbers authored
This introduces n hypotheses and destructs the nth one.

 01 Jun, 2016 3 commits


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

Robbert Krebbers authored

Robbert Krebbers authored

 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

 24 May, 2016 5 commits


Robbert Krebbers authored
Rationale: to make the code closer to what is on paper, I want the notations to look like quantifiers, i.e. have a binder builtin. I thus introduced the following notations: [★ map] k ↦ x ∈ m, P [★ set] x ∈ X, P The good thing  contrary to the notations that we had before that required an explicit lambda  is that type annotations of k and x are now not printed making goals much easier to read.

Robbert Krebbers authored

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.
