 31 Oct, 2017 2 commits


Robbert Krebbers authored

Robbert Krebbers authored

 30 Oct, 2017 14 commits


Robbert Krebbers authored

Robbert Krebbers authored

Robbert Krebbers authored
(All the later lemmas are now prefixed by later_, and dito for laterN, and except_0).

Robbert Krebbers authored

Aleš Bizjak authored

Robbert Krebbers authored

Robbert Krebbers authored

Robbert Krebbers authored
The absence of this axiom has two consequences:  We no longer have `■ (P ∗ Q) ⊢ ■ P ∗ ■ Q` and `□ (P ∗ Q) ⊢ □ P ∗ □ Q`, and as a result, separating conjunctions in the unrestricted/persistent context cannot be eliminated.  When having `(P ∗ ⬕ Q) ∗ P`, we do not get `⬕ Q ∗ P`. In the proof mode this means when having: H1 : P ∗ ⬕ Q H2 : P We cannot say `iDestruct ("H1" with "H2") as "#H1"` and keep `H2`. However, there is now a type class `PositiveBI PROP`, and when there is an instance of this type class, one gets the above reasoning principle back. TODO: Can we describe positivity of individual propositions instead of the whole BI? That way, we would get the above reasoning principles even when the BI is not positive, but the propositions involved are.

Robbert Krebbers authored
Otherwise, ownership of cores in our ordered RA model will not be persistent.

Robbert Krebbers authored

Robbert Krebbers authored
As Aleš observed, in the ordered RA model it is not, unless the order on the unit is timeless.

Robbert Krebbers authored

Robbert Krebbers authored
Thanks to discussions with Ales and Amin.

Robbert Krebbers authored
