Rubex

Rubex is a Ruby-like language for writing Ruby C extensions.

Rubex is a language that makes writing CRuby C extensions as simple as writing Ruby. It does this by providing a syntax that is the perfect blend of the elegance of Ruby and the power of C. Rubex compiles to C and implicitly interfaces with the Ruby VM in a manner that is completely transparent to the programmer.

Rubex keeps you happy even when writing C extensions.

Status

Table of Contents

• Quick Introduction
• Installation
• Usage
• Tutorial
• Syntax
• Roadmap
• Acknowledgements

Quick Introduction

Consider this Ruby code for computing a fibonnaci series and returning it in an Array:

class Fibonnaci
  def compute(n)
    i = 1, prev = 1, current = 1, temp
    arr = []

    while i < n do
      temp = current
      current = current + prev
      prev = temp
      arr.push(prev)
      i += 1
    end

    arr
  end
end

If you decide to port this to a C extension, the code will look like so:

#include <ruby.h>
#include <stdint.h>

void Init_a ();
static VALUE Fibonnaci_compute (int argc,VALUE* argv,VALUE self);

static VALUE Fibonnaci_compute (int argc,VALUE* argv,VALUE self)
{
  int n,i,prev,current,temp;
  VALUE arr;

  if (argc < 1) {
    rb_raise(rb_eArgError, "Need 1 args, not %d", argc);
  }

  n       = NUM2INT(argv[0]);
  i       = 1;
  prev    = 1;
  current = 1;
  arr     = rb_ary_new2(0);

  while (i < n)
  {
    temp = current;
    current = current + prev;
    prev = temp;
    rb_funcall(arr, rb_intern("push"), 1 ,INT2NUM(prev));
    i = i + 1;
  }

  return arr;
}

void Init_a ()
{
  VALUE cls_Fibonnaci;

  cls_Fibonnaci = rb_define_class("Fibonnaci", rb_cObject);

  rb_define_method(cls_Fibonnaci ,"compute", Fibonnaci_compute, -1);
}

However, if you decide to write a C extension using Rubex, the code will look like this!:

class Fibonnaci
  def compute(int n)
    int i = 1, prev = 1, current = 1, temp
    array = []

    while i < n do
      temp = current
      current = current + prev
      prev = temp
      array.push(prev)
      i += 1
    end

    return array
  end
end

Notice the only difference between the above Rubex code and Ruby is the specification of explicit int types for the variables. Above Rubex code will automatically compile into C code and will also implicitly interface with the Ruby VM without you having to remember any of the APIs.

Rubex also takes care of the initial setup and compilation of the C files, so all you need to do is execute a bunch of commands and your extension is up and running!

Installation

To build, requires Ruby version >= 2.3.0

The gem as of now has not reached v0.1. However, you can try it out with:

git clone https://github.com/v0dro/rubex.git
cd rubex
bundle install
rake install

Usage

Installing the gem will also install the rubex binary. You can now write a Rubex file (with a .rubex file extension) and compile it into C code with:

rubex file_name.rubex

This will produce the translated C code and an extconf.rb file inside a directory called file_name. CD into the directory, and run the extconf.rb file with:

ruby extconf.rb

This will produce a Makefile. Run make to compile the generated C file and generate a .so shared object file that can be used in any Ruby script.

Tutorial

Give yourself 5 min and go through the TUTORIAL. Convert a part of your C extension to Rubex and see the jump in cleanliness and productivity for yourself.

Syntax

Read the full Rubex reference in REFERENCE.

Roadmap

See the CONTRIBUTING and the GitHub issue tracker for future features.

Acknowledgements

• The Ruby Association (Japan) for providing the initial funding for this project through the Ruby Association Grant 2016.
• Koichi Sasada (@ko1) and Kenta Murata (@mrkn) for their support and mentorship throughout this project.
• Fukuoka Ruby Award 2017.