CHANGELOG.md



In this changelog, we document "large-ish" changes to Iris that affect even the
way the logic is used on paper.  We also mention some significant changes in the
Coq development, but not every API-breaking change is listed.  Changes marked
[#] still need to be ported to the Iris Documentation LaTeX file(s).

Iris 3.0 (unfinished)

There now is a deprecation process.  The modules *.deprecated
contain deprecated notations and definitions that are provided for
backwards compatibility and will be removed in a future version of Iris.
View shifts are radically simplified to just internalize frame-preserving
updates.  Weakestpre is defined inside the logic, and invariants and view
shifts with masks are also coded up inside Iris.  Adequacy of weakestpre
is proven in the logic.
Use OFEs instead of COFEs everywhere.  COFEs are only used for solving the
recursive domain equation.  As a consequence, CMRAs no longer need a proof
of completeness.
(The old cofeT is provided by algebra.deprecated.)
Renaming and moving things around: uPred and the rest of the base logic are
in base_logic, while program_logic is for everything involving the
general Iris notion of a language.
Changed notation for embedding Coq assertions into Iris.  The new notation
is ⌜φ⌝.  Also removed = and ⊥ from the Iris scope.
(The old notations are provided in base_logic.deprecated.)
Up-closure of namespaces is now a notation (↑) instead of a coercion.
With invariants and the physical state being handled in the logic, there
is no longer any reason to demand the CMRA unit to be discrete.
The language can now fork off multiple threads at once.
Local Updates (for the authoritative monoid) are now a 4-way relation
with syntax-directed lemmas proving them.


Iris 2.0

[heap_lang] No longer use dependent types for expressions.  Instead, values
carry a proof of closedness.  Substitution, closedness and value-ness proofs
are performed by computation after reflecting into a term langauge that knows
about values and closed expressions.
[program_logic/language] The language does not define its own "atomic"
predicate.  Instead, atomicity is defined as reducing in one step to a value.
[program_logic] Due to a lack of maintenance and usefulness, lifting lemmas
for Hoare triples are removed.


Iris 2.0-rc2
This version matches the final ICFP paper.

[algebra] Make the core of an RA or CMRA a partial function.
[program_logic/lifting] Lifting lemmas no longer round-trip through a
user-chosen predicate to define the configurations we can reduce to; they
directly relate to the operational semantics.  This is equivalent and
much simpler to read.


Iris 2.0-rc1
This is the Coq development and Iris Documentation as submitted to ICFP.