# IRIS COQ DEVELOPMENT

This is the Coq development of the [Iris Project](http://iris-project.org).

## Prerequisites

This version is known to compile with:

 - Coq 8.6.1 / 8.7.0 / 8.7.1 / 8.7.2
 - Ssreflect 1.6.4
 - A development version of [std++](https://gitlab.mpi-sws.org/robbertkrebbers/coq-stdpp)

If you need to work with Coq 8.5, please check out the
[iris-3.0 branch](https://gitlab.mpi-sws.org/FP/iris-coq/tree/iris-3.0).

## Installing via opam

To obtain the latest stable release via opam (1.2.2 or newer), you have to add
the Coq opam repository:

    opam repo add coq-released https://coq.inria.fr/opam/released

Then you can do `opam install coq-iris`.

To obtain a development version, add the Iris opam repository:

    opam repo add iris-dev https://gitlab.mpi-sws.org/FP/opam-dev.git

## Building from source

When building Iris from source, we recommend to use opam (1.2.2 or newer) for
installing Iris's dependencies.  This requires the following two repositories:

    opam repo add coq-released https://coq.inria.fr/opam/released
    opam repo add iris-dev https://gitlab.mpi-sws.org/FP/opam-dev.git

Once you got opam set up, run `make build-dep` to install the right versions
of the dependencies.

Run `make -jN` to build the full development, where `N` is the number of your
CPU cores.

To update Iris, do `git pull`.  After an update, the development may fail to
compile because of outdated dependencies.  To fix that, please run `opam update`
followed by `make build-dep`.

## Directory Structure

* The folder [algebra](theories/algebra) contains the COFE and CMRA
  constructions as well as the solver for recursive domain equations.
* The folder [base_logic](theories/base_logic) defines the Iris base logic and
  the primitive connectives.  It also contains derived constructions that are
  entirely independent of the choice of resources.
  * The subfolder [lib](theories/base_logic/lib) contains some generally useful
    derived constructions.  Most importantly, it defines composeable
    dynamic resources and ownership of them; the other constructions depend
    on this setup.
* The folder [program_logic](theories/program_logic) specializes the base logic
  to build Iris, the program logic.   This includes weakest preconditions that
  are defined for any language satisfying some generic axioms, and some derived
  constructions that work for any such language.
* The folder [proofmode](theories/proofmode) contains the Iris proof mode, which
  extends Coq with contexts for persistent and spatial Iris assertions. It also
  contains tactics for interactive proofs in Iris. Documentation can be found in
  [ProofMode.md](ProofMode.md).
* The folder [heap_lang](theories/heap_lang) defines the ML-like concurrent heap
  language
  * The subfolder [lib](theories/heap_lang/lib) contains a few derived
    constructions within this language, e.g., parallel composition.
    For more examples of using Iris and heap_lang, have a look at the
    [Iris Examples](https://gitlab.mpi-sws.org/FP/iris-examples).
* The folder [tests](theories/tests) contains modules we use to test our
  infrastructure. Users of the Iris Coq library should *not* depend on these
  modules; they may change or disappear without any notice.

## Further Documentation

* A LaTeX version of the core logic definitions and some derived forms is
  available in [docs/iris.tex](docs/iris.tex).  A compiled PDF version of this
  document is [available online](http://plv.mpi-sws.org/iris/appendix-3.1.pdf).
* Information on how to set up your editor for unicode input and output is
  collected in [Editor.md](Editor.md).
* The Iris Proof Mode (IPM) is documented at [ProofMode.md](ProofMode.md)

## Case Studies

The following is a (probably incomplete) list of case studies that use Iris, and
that should be compatible with this version:

* [Iris Examples](https://gitlab.mpi-sws.org/FP/iris-examples) is where we
  collect miscellaneous case studies that do not have their own repository.
* [LambdaRust](https://gitlab.mpi-sws.org/FP/LambdaRust-coq/) is a Coq
  formalization of the core Rust type system.
* [Iris Atomic](https://gitlab.mpi-sws.org/FP/iris-atomic/) is an experimental
  formalization of logically atomic triples in Iris.

## For Developers: How to update the std++ dependency

* Do the change in std++, push it.
* Wait for CI to publish a new std++ version on the opam archive, then run
  `opam update iris-dev`.
* In Iris, change the `opam` file to depend on the new version.
* Run `make build-dep` (in Iris) to install the new version of std++.
  You may have to do `make clean` as Coq will likely complain about .vo file
  mismatches.