CSC/ECE 517 Fall 2010/ch3 3i MM
Introduction
Ruby is a high-level, dynamic programming language that is useful for everything from short scripting assignments, to entire web applications and desktop GUI applications. However, there are inherent downsides to using Ruby come because of its interpreted, dynamic nature. Using C code for some tasks can improve memory usage, and raw execution speed when compared to Ruby [1].
However, what if you could combine the good performance aspects of C, with with the dynamic elements of Ruby? It seems like it should be possible, since Ruby is actually written in C.
Using C from Ruby
Following are some overviews and examples of ways to create C or C++ extensions to Ruby.
Ruby C API
README.EXT
The README.EXT file contains the latest information and an overview of how to create Ruby extensions in C. It is an invaluable source of information, and is included in any source code distribution of Ruby. The link is to the latest HEAD version in Ruby's official subversion repository, but you may want to read the version that came with your installed version of Ruby.
In Unix-like distributions, for example, this file may be installed installed in '/usr/share/doc/ruby1.8-dev/README.EXT.gz'. To read, from a command prompt type:
> zless /usr/share/doc/ruby1.8-dev/README.EXT.gz
VALUE
...
Example
RubyInline
SWIG
SWIG is a popular wrapper generator that can produce wrappers for C and C++ code in several high level programming languages, including Perl, Python, and Ruby.
Using Ruby from C
README.EXT
Once again, this file, included in the Ruby source code, has a section on using Ruby features from C. Section 2.2 is a brief overview of some techniques for doing this.