Code Generation in Action

Appendix A. A brief introduction to Ruby

In this appendix, we provide a brief overview of the basics of the Ruby language.

Ruby programs and scripts are simple text files that have the filename extension .rb. To execute a Ruby program, you simply type

ruby file_name.rb

where file_name represents the name of the Ruby file you wish to run.

Ruby is an imperative language, and as such, a program file consists of a set of linear command invocations similar to C, C++, Perl, or Java. The Hello World application in Ruby is simply

print "Hello World\n"

Carriage returns are used to delineate commands. For example,

print "This is "
print "a test\n"

prints “This is a test” on a single line by calling print twice. You can use a semicolon if you prefer ...