SCHeMe UnterstüTZung

schmutz is a library to declare Scheme bindings for C++ code using a simple embedded DSL. Think of it as Boost.Python or LuaBind but for Scheme. At the moment, it only works with the GNU Guile Scheme implementation, but multiple backend support is considered for the future.

• Documentation (Contents)
• Code (GitHub)

This research project is part of a long-term vision helping interactive and concurrent C++ programs become easier to write. Support our vision by becoming a patron or buying a sponsorship package: [email protected]

Example

In the C++ world...

#include <scm/scm.hpp>
#include <numeric>

class counter {
    std::size_t count_ = 0;
public:
    std::size_t get() const { return count_; }
    void tick() { ++count_; }
};

int fold_args(scm::val fn, scm::val fst, scm::args xs) {
    return std::accumulate(xs.begin(), xs.end(), fst, fn);
}

extern "C" void init_module() {
    scm::type<counter>("counter")
        .constructor()
        .define("get", &counter::get)
        .define("tick!", &counter::tick);
    scm::group()
        .define("the-answer", [] { return 42; })
        .define("fold-args", fold_args);
}

In the Scheme world...

(use-modules (example module)
             (oop goops)
             (rnrs base))

(let ((cnt (counter)))
  (assert (is-a? cnt <counter>))
  (counter-tick! cnt)
  (counter-tick! cnt)
  (counter-tick! cnt)
  (assert (= 3 (counter-get cnt))))

(assert (= (the-answer) 42))
(assert (= 6 (fold-args + 0 1 2 3)))

Usage

This is a header only library. As long as you already have Guile installed, you can just copy the scm subfolder somewhere in your include path.

Otherwise, if you are using the Guix package manager you can just:

git clone https://github.com/arximboldi/schmutz
guix package -f schmutz/guix.scm -i

Or if you are using the Nix package manager you can just:

nix-env -if https://github.com/arximboldi/schmutz/archive/master.tar.gz

Alternatively, you can use CMake to install the library in your system once you have manually cloned the repository:

mkdir -p build && cd build
cmake .. && sudo make install

Development

In order to develop the library, you will need to compile and run the examples, tests and benchmarks. These require some additional tools. The easiest way to install them is by using the Guix package manager or the Nix package manager. At the root of the repository just type:

guix environment -l guix.scm

Or alternatively:

nix-shell

This will download all required dependencies and create an isolated environment in which you can use these dependencies, without polluting your system.

Then you can proceed to generate a development project using CMake:

mkdir build && cd build
cmake ..

From then on, one may build and run all tests by doing:

make check

License

This software is licensed under the Boost Software License, Version 1.0.

---

schmutz - Scheme Unterstüzung
Copyright (C) 2017 Juan Pedro Bolivar Puente

Boost Software License - Version 1.0 - August 17th, 2003

Permission is hereby granted, free of charge, to any person or
organization obtaining a copy of the software and accompanying
documentation covered by this license (the "Software") to use,
reproduce, display, distribute, execute, and transmit the Software,
and to prepare derivative works of the Software, and to permit
third-parties to whom the Software is furnished to do so, all
subject to the following:

The copyright notices in the Software and this entire statement,
including the above license grant, this restriction and the
following disclaimer, must be included in all copies of the
Software, in whole or in part, and all derivative works of the
Software, unless such copies or derivative works are solely in the
form of machine-executable object code generated by a source
language processor.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE AND
NON-INFRINGEMENT. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR ANYONE
DISTRIBUTING THE SOFTWARE BE LIABLE FOR ANY DAMAGES OR OTHER
LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.