Template Coq

Template Coq is a quoting library for Coq. It takes Coq terms and constructs a representation of their syntax tree as a Coq inductive data type. The representation is based on the kernel's term representation.

In addition to this representation of terms, Template Coq includes:

• Reification of the environment structures, for constant and inductive declarations.

• Denotation of terms and global declarations

The branch master is stable and works with Coq 8.6, an opam package is available.

The coq-8.7, branch is in development and contains additional features:

• Complete reification and denotation of CIC terms, including universes

• A monad for manipulating global declarations, calling the type checker, and inserting them in the global environment, in the stype of MetaCoq/MTac.

• A partial type-checker for the Calculus of Inductive Constructions, runable as a plugin.

• Example plugins built on top of this.

Documentation

The 8.7 branch documentation (coqdoc files) and pretty-printed HTML versions of the translations are available.

Papers

• The system was presented at Coq'PL 2018

• "Towards Certified Meta-Programming with Typed Template-Coq" A. Anand, S. Boulier, C. Cohen, M. Sozeau and N. Tabareau. Submitted.

Credits

Template-Coq was originally developed by Gregory Malecha, and is now developed by Abhishek Anand, Simon Boulier and Matthieu Sozeau.

Contributors include Yannick Forster, Cyril Cohen and Nicolas Tabareau.

Copyright (c) 2014-2018 Gregory Malecha
Copyright (c) 2015-2018 Abhishek Anand, Matthieu Sozeau
Copyright (c) 2017-2018 Simon Boulier, Nicolas Tabareau, Cyril Cohen

This software is distributed under the terms of the MIT license. See LICENSE for details.

Branches

• The current stable branch is master and works with Coq 8.6. It includes only the syntax part of Template-Coq and the ability to make plugins.

• The development branch is coq-8.7, which includes:

  • The full syntax of CIC: Ast

  • The typing judgment of CIC: Typing

  • A partial type-checker implementation: Checker

  • The TemplateMonad datatype and the Run TemplateProgram command to run template programs: Ast

Examples of plugins

• a plugin to add a constructor in test-suite/add_constructor.v
• a parametricity plugin in translations/tsl_param.v
• a plugin to negate funext in translations/fun.v

Installation instructions

Install from scratch (for 8.6 and development versions)

To get the source code:

# git clone https://github.com/Template-Coq/template-coq.git
# git checkout -b coq-8.7 origin/coq-8.7
# git status

Check that you are indeed on the coq-8.7 branch.

Requirements

To compile the library, you need:

• Coq 8.7.1 (8.7.0 might work as well) and
• OCaml (tested with 4.04.1, beware that OCaml 4.06.0 can produce linking errors on some platforms).

Requirements through opam

The easiest way to get both is through opam:

You might want to create a "switch" (an environment of opam packages) for Coq if you don't have one yet:

# opam switch -A 4.04.1 coq.8.7.1
# eval `opam config env`

This creates the coq.8.7.1 switch which initially contains only the basic OCaml 4.04.1 compiler, and puts you in the right environment (check with ocamlc -v).

Once in the right switch, you can install Coq using:

# opam pin add coq 8.7.1 

Pinning coq prevents opam from trying to upgrade it afterwards, in this switch. If the command is successful you should have coq available (check with coqc -v).

Compile

Once in the right environment, Use:

• make to compile the template-coq plugin (and the checker in coq-8.7)

• make translations to compile the translation plugins (in coq-8.7)

• make test-suite to compile the test suite

• make install to install the plugin in coq's user-contrib local library. Then the Template namespace can be used for Require Import statements, e.g. From Template Require Import All..

Install with OPAM (for 8.6 version only)

Add the Coq repository:

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

and run:

opam install coq-template-coq

To get beta versions of Coq, you might want to activate the repository:

opam repo add coq-core-dev https://coq.inria.fr/opam/core-dev

How to Use

Check test-suite/demo.v for examples.

Unless you installed the library, you must add the theories directory to your Coq load path with the prefix Template. This can be done on the command line by adding:

coqc ... -R <path-to-theories> -as Template ...

or inside a running Coq session with:

Add LoadPath "<path-to-theories>" as Template.

Because paths are often not portable the later is not recommended.

If you use Emacs and Proof General, you can set up a .dir-locals.el with the following code:

((coq-mode . ((coq-load-path . (
 (nonrec "<absolute-path-to-theories>" "Template")
 )))))

As long as you don't check this file into a repository things should work out well.

Bugs

Please report any bugs (or feature requests) on the github issue tracker