This repo has been moved to https://github.com/plclub/hs-to-coq.
We will no longer update the code here. All issues and pull requests should be reported on the repo.
This repository contains a converter from Haskell code to equivalent Coq code, as part of the CoreSpec component of the DeepSpec project.
CPP'18 paper “Total Haskell is Reasonable Coq” by Antal Spector-Zabusky, Joachim Breitner, Christine Rizkallah, and Stephanie Weirich. This paper describes the following examples:
- bag Multiset implementation from GHC's implemention
- compiler Hutton's razor
- base-src The sources of the
base/
directory
ICFP'18 paper "Ready, set, verify! applying hs-to-coq to real-world Haskell code (experience report)" by Joachim Breitner, Antal Spector-Zabusky, Yao Li, Christine Rizkallah, John Wiegley, and Stephanie Weirich. This paper describes the verification of the containers library.
Documentation for the hs-to-coq
tool is
available!
hs-to-coq
uses Coq 8.10.2 and ssreflect.
The recommended way of building hs-to-coq
is to use stack
. If you have not
setup stack before, run:
stack setup
To build hs-to-coq
, then run
stack build
(hs-to-coq
can be built with GHC 8.4, 8.6, 8.8, and 8.10. However, the repo
only contains the translation of Haskell libraries such as base
from GHC
8.4. Therefore, it is advised to build hs-to-coq
with GHC 8.4 if you plan to
use example translations contained in this repo.)
This repository comes with a version of (parts of the) Haskell base library converted to Coq, which you will likely need if you want to verify Haskell code.
You must have Coq 8.10.2 and ssreflect to build the base library. To install these tools:
opam repo add coq-released https://coq.inria.fr/opam/released
(for SSReflect and MathComp)opam update
opam install coq.8.10.2 coq-mathcomp-ssreflect.1.10.0
Once installed, you can build the base library with
make -C base
Th directory base-thy/
contains auxillary definitions and lemmas, such as
lawful type-class instances. You can build these with
make -C base-thy
To use the tool, run it (using stack
), passing the Haskell file to be
translated and an output directory to write to:
stack exec hs-to-coq -- -o output-directory/ Input/File.hs
Very likely you want to make use of the base/
library. In that case, make
sure you pass -e base/edits
.
Have a look at the example directories, e.g. examples/successors
, for a
convenient Makefile
based setup.
The edits
file contains directives to hs-to-coq
for ignoring or
transforming some Haskell constructs into proper Coq.
For example, it is common in Haskell to have the following code:
module Foo where
...
newtype SomeType = SomeType { someFiled :: Integer }
Coq has a single namespace for types and values hence the type name
will conflict with constructor name. One can pass -e edit
file
containing custom directives to ensure correctness of generated code
with the following directive:
rename value Foo.SomeType = Foo.MkSomeType
See the manual for documentation for the edits files.
-
The
examples/
directories contains a number of example translation and verification projects, including-
ghc Modules of GHC itself.
-
containers Modules from the
containers
library, includingData.Set
andData.IntSet
-
bag Multiset implementation from GHC's implemention
-
successors Successors Monad
-
compiler Hutton's razor
-
quicksort Quicksort
-
rle Run-length encoding
-
coinduction Translating infinite data structures
-
base-src The sources of the
base/
directory -
tests Simple unit-tests
-
base-tests Unit-tests that require
base/
Some examples use git submodule, so run
git submodule update --init --recursive
once.
-
structural-isomorphism-plugin
: (In progress.) A GHC plugin that connects the re-extracted converted code back into GHC, allowing us to run Haskell programs against verified/verifiable code. Currently does not work.