TweetFollow Us on Twitter

Apple, Meet Ruby

Volume Number: 25
Issue Number: 11
Column Tag: Programming

Apple, Meet Ruby

A gentle introduction

by Rich Morin

Welcome

Mac OS X is very popular with Ruby developers, but most Mac OS X developers are unfamiliar with Ruby. This is unfortunate, because the Ruby language, ecosystem, and community have a lot to offer. If you've been curious about Ruby, read on...

The Ruby Language

The Ruby language was developed by Yukihiro Matsumoto (Matz), as a way to "make programmers happy". It does this by providing powerful features, an elegant syntax, and a very accommodating attitude. The following description, while terse, covers most of the specifics:

Ruby is a dynamic programming language with a complex but expressive grammar and a core class library with a rich and powerful API. Ruby draws inspiration from Lisp, Smalltalk, and Perl, but uses a grammar that is easy for C and Java programmers to learn. Ruby is a pure object-oriented language, but it is also suitable for procedural and functional programming styles. It includes powerful metaprogramming capabilities and can be used to create domain-specific languages or DSLs.

-- "The Ruby Programming Language"

Possibly because the term "scripting language" didn't get enough respect, purveyors of these tools now call them "dynamic programming languages". So, Ruby has all of the convenience (ie, expressive syntax, low overhead, good OS integration) you'd expect to find in a scripting language. However, because it is a "pure object-oriented language", it is capable of handling much larger programming tasks than you might otherwise expect.

Ruby's grammar and dynamic nature (eg, metaprogramming, DSLs) combine to make it very expressive. So, Ruby code tends to be surprisingly small. Even a simple transliteration of Objective-C into Ruby can yield a substantial reduction in code size (a 5x reduction in character counts is quite plausible). This means a lot less code to write, read, and debug.

Ruby supports convenient interactive modes for debugging and general experimentation. As a stand-alone program, Interactive Ruby (irb) allows programmers to try out arbitrary code. Used in the context of a running program (eg, as a Rails "console"), it can allow developers to examine data, try out method calls, etc. Here's a sample irb session, to give you a small taste:

% irb -simple-prompt
>> 2+2
=> 4
>> s = "a string"
=> "a string"
>> s.reverse
=> "gnirts a"
>> ^D

Ruby is easy and pleasant to use, while providing a rich (and quite extensible) set of features. Although Ruby's origins are eclectic, Matz has excellent taste in language design. Consequently, Ruby offers (IMHO) a smooth integration of concepts and syntax. For details, see my weblog entry, "How I arrived at Ruby".

However, if Ruby is such a great language, who's using it? A few years ago, there wasn't a very good answer to this. Although Ruby was reputed to be "big in Japan", it was mostly used by system administrators, language aficionados, etc. The scripting API for Google SketchUp, although useful and fun to play with, did not exactly put Ruby in the big leagues.

Ruby rose to prominence, however, as the foundation for David Heinemeier Hansson's web development framework, Ruby on Rails. As Rails became popular, many web developers also learned Ruby. Other Ruby-based web frameworks (eg, Merb, Rack, Sinatra, Waves) have since been developed, making Ruby an important player in web development.

Any substantial web site uses a mixture of technologies: databases, routers, servers, etc. So, web developers have to be facile in a variety of languages and tools. Ruby is important as the "glue language", but the heavy lifting may well be done by tools written in C, Erlang, Java, etc.

Although Ruby can be run on any modern operating system, most Ruby code is developed on Mac OS X. In particular, Apple laptops dominate the picture at Ruby conferences, hackfests, and meetings. OSX-only tools such as Keynote and TextMate dominate the presentations.

Ezra Zygmuntowicz took advantage of this fact in a talk on cloud computing technologies (eg, chef, nanites, rabbitmq) at RailsConf 2009. He had all of the Mac users in the room download some server code, then ran some parallel-processing demonstrations from the podium, causing a chorus of Macs to "say" snippets of text.

Testing

The Ruby community emphasizes testing very strongly, putting it in the center of the development process. In fact, the definition for the Ruby language itself (including assorted variations) is captured by RubySpec, a test suite containing tens of thousands of executable "specs".

Tools and practices for "behavior-driven development" (BDD) and "test-driven development" (TDD) are also very popular. In these approaches, developers are encouraged to write tests first, verifying that they do not pass. Then, developers write enough code to make the tests pass. Once everything is "green", they are free (and encouraged) to refactor (ie, tidy up) the code.

This produces various levels of tests (eg, unit, functional, integration), giving the project a useful (and very comforting) "safety net" for changes. In many shops, "continuous integration" (CI) tools run the test suite after each code check-in. If a developer makes a change that breaks a test, the CI suite will let the developer (and maybe the entire shop :-) know about it.

Because most Ruby development is done on Rails (ie, web-based) applications, most Ruby deployment uses Linux-based PCs. The reasons are fairly straightforward. Commodity PCs make very economical servers. Also, Linux supports a variety of technologies (eg, clustering, virtual machines) that are useful for servers.

So, Rails developers have created a large number of tools for deployment, remote testing, etc. Many of these are also useful for network administration tasks, such as installing and configuring user applications.

In fact, one of the biggest differences between Mac and Ruby development is the wealth of community-based libraries, frameworks, and other tools. Instead of relying on Apple (and a handful of third-party vendors), the Ruby community develops its own infrastructure and shares it freely.

Implementations

Leopard ships with the original Ruby (1.8.6) implementation, known colloquially as MRI (Matz's Ruby Interpreter). Snow Leopard increments the version to 1.8.7. Many other variants are available or under development, including:

  • Duby - Ruby-like syntax with static types

  • ERuby - Embedded Ruby (for templating)

  • HotRuby - Ruby on JavaScript and Flash

  • IronRuby - Ruby on .NET (DLR)

  • JRuby - Ruby on Java

  • MacRuby - Ruby on Objective-C

  • MagLev - Ruby with object persistence

  • Rubinius - Ruby on Ruby and C

  • RubyCocoa - MRI with a Cocoa bridge

  • YARV - MRI, the next generation

Some of these variants change the language itself; others add features or provide access to particular run-time environments. RubySpec (the executable specification suite) provides guidance to developers of alternative implementations. Not surprisingly, RubySpec is also a critical resource as Ruby moves to new versions (eg, from 1.8.6 to 1.9 and 2.0).

The most interesting of these variants, from the perspective of a Mac developer, is MacRuby. MacRuby allows Ruby programs access to the entire range of Objective-C capabilities, including some that the base language makes difficult or impossible (eg, redefining ObjC methods at runtime). All without using a bridge (like RubyCocoa or PyObj-C).

The experimental branch, as of early July, uses LLVM to perform Just In Time (JIT) compilation of Ruby into machine code. Ahead Of Time (AOT) compilation is also in prospect, so the ability to run MacRuby code in sanctioned iPhone apps appears quite likely to present itself within a matter of months. Currently, as of beta 5, MacRuby can create a Mach-O object from Ruby source code. Stay tuned...

The Ruby Community

Rubyists are a motley crew. Some of us came because of the language itself. If so, our background may be in another dynamic language such as JavaScript, Lisp, Perl, PHP, Python, or Smalltalk. Others, who came to Ruby because of Rails, may have Java, JavaScript, and/or PHP experience. This diversity makes conversations interesting, to say the least!

Rubyists also tend to be "early adopters" of new technology, both in and out of the Ruby language. For example, CouchDB, Erlang, and jQuery get a lot of attention, despite the fact that they have nothing directly to do with Ruby. Basically, Rubyists are pretty agnostic about technology origins and implementation details, as long as it meets their needs.

This also extends to various aspects of "social computing". About a year ago, the entire Rails community switched to Git and GitHub for revision control and code exchange. Rubyists also tend to be active participants on email lists, IM, IRC, Twitter, wikis, etc. Finally, Internet-based videos (eg, screencasts, conference talks) are very popular as a way to present ideas and demonstrate technology.

Conference Videos

Speaking of videos, I really love the ability to attend Ruby conferences from the comfort of my office chair. I don't have to worry about missing a parallel track, never get stuck in a boring or irrelevant session, and have the ability to pause or back up when I start getting lost.

Confreaks is by far the biggest source of Ruby-related conference videos, but events such as MerbCamp and the South Carolina Ruby Conference are also recorded. My weblog entry, "Video Resources for Rubyists", has a relatively complete list.

Even when the entire conference isn't recorded for posterity (tsk!), occasional presentations may be recorded. O'Reilly, for example, commonly records keynotes. I'm hoping they will start recording all of their conference sessions, but keynotes are certainly better than nothing.

Live Conferences

Of course, videos do not provide the full conference experience. Less travel and dislocation, to be sure, but no opportunity for hallway discussions, BOFs, etc. So, taking in an occasional conference is quite worthwhile. This year, I have attended GoGaRuco (San Francisco) and RailsConf (Las Vegas); a couple of others are on my "wish list".

More than a dozen Ruby or Rails conferences are held each year. Some, like RailsConf and RubyConf, are big-tent, multi-track events; others tend to be smaller, single-track events. Both styles have their advantages and disadvantages.

About half of the Ruby and Rails conferences are held in the USA (eg, CA, DC, FL, HI, NC, NV, OH, TX, UT). Others are held around the world: Argentina (Locos X Rails), Australia (Rails Camp), Canada (FutureRuby, Ruby in the Rain), Europe (EuRuKo, Rails Konferenz, Ruby Fools, Scotland on Rails), and Japan (RubyKaigi). There are even some specialized events, such as the one-day "Ruby on OS X" conference and "erubycon" (Enterprise Ruby Conference). A web search (eg, "Conference Rails Ruby") will bring up lots of listings.

Local Groups

There are dozens of local groups for Ruby and Rails developers. Meetings often have invited speakers, but "hack sessions" and "lightning talks" are also popular. Announcements (eg, firms looking for Rails developers) are also a common feature.

Although groups are scattered around the world, the distribution is far from even. In the San Francisco Bay Area, for example, we have half a dozen groups that meet regularly and a few other events (eg, hackfests, seminars) that surface on occasion. The Ruby Brigade and Meetup pages are useful for finding (and if need be, starting) new groups.

Books

I'm a big fan of technical books, in both paper and online formats. I mark up the paper ones with errata and notes, add Post-it tabs liberally, and generally "make them my own". I find the online versions harder to read (and impossible to mark up), but much better for some kinds of searching and rapid access. So, I often get both versions.

As a MacTech reader, you're likely to be familiar with at least a few programming languages. Objective-C, in particular is de rigeur for Mac OS X application developers. So, I'm going to suggest some books that should help you get going in Ruby, without wasting your time.

Programming Ruby is the canonical "handbook" for Ruby. It contains a fairly complete introduction to the language, covers the standard classes and modules quite well, and covers a smattering of ancillary topics (eg, common add-on libraries). Versions are available for both the traditional (1.8) and upcoming (1.9) versions of the language.

The Ruby Programming Language is a definitive reference for Ruby (after all, Matz is a co-author!). It covers both Ruby 1.8 and 1.9, making comparisons as needed. I've been working my way (carefully) through the book, learning about language details I've missed in the past. I'm also working on Ruby Best Practices, which covers a lot of (deservedly) popular Ruby programming idioms.

Design Patterns in Ruby, despite its title, might well be the best introduction to Ruby for an Objective-C programmer. It begins with a slightly simplistic description of the language, then dives into assorted "design patterns". Typically, it begins with an approach that mimics that of the original (ie, in Design Patterns), but it often uses that as a starting point to discuss more and more Rubyish approaches.

The Well-Grounded Rubyist is a bit of a sleeper. The early chapters are paced pretty slowly, with rather elementary material. However, the author is able to maintain the same sedate (and unthreatening) pace as he delves further and further into Ruby arcana. So, if you really want to learn how to "do Ruby", this book is a must-read.

There are a variety of "cookbooks" for Ruby. I find them to be quite handy when I'm looking for an idiom or simply an example of how to use a particular part of the language. I use Ruby Cookbook a lot, but also dive into The Ruby Way and Enterprise Integration with Ruby on occasion. The latter book is particularly useful for topics such as LDAP and XML.

Bibliography and References

Here are citations for some of the books and web sites mentioned above:

Black, David A. The Well-Grounded Rubyist. Manning, 2009.

Brown, Gregory T. Ruby Best Practices. O'Reilly, 2009.

Carlson, Lucas and Richardson, Leonard. Ruby Cookbook. O'Reilly, 2006.

Flanagan, David and Matsumoto, Yukihiro. The Ruby Programming Language. O'Reilly, 2008.

Fulton, Hal. The Ruby Way. 2nd. Edn. Addison-Wesley, 2006.

Gamma, Erich, et al. Design Patterns. Addison-Wesley, 1995.

Schmidt, Maik. Enterprise Integration with Ruby. Pragmatic Bookshelf, 2006.

Thomas, Dave, et al. Programming Ruby. 2nd. Edn. Pragmatic Bookshelf, 2005.

Thomas, Dave, et al. Programming Ruby 1.9. Pragmatic Bookshelf, 2009.

Git - http://git-scm.com

GitHub - http://github.com

Google SketchUp Ruby API - http://code.google.com/apis/sketchup

IronRuby - http://www.ironruby.net

JRuby - http://jruby.codehaus.org

LLVM - http://llvm.org

MacRuby - http://macruby.org

MagLev - http://maglev.gemstone.com

Merb - http://merbivore.com

Rack - http://rack.rubyforge.org

Rich Morin's weblog - http://www.cfcl.com/rdm/weblog

Rubinius - http://rubini.us

Ruby APIs - http://www.ruby-doc.org

Ruby on OS X - http://rubyonosx.com

Ruby on Rails - http://rubyonrails.org

RubyCocoa - http://rubycocoa.sourceforge.net

Sinatra - http://www.sinatrarb.com

TextMate - http://macromates.com

Waves - http://rubywaves.com

YARV - http://www.atdot.net/yarv

Aloha on Rails - http://www.alohaonrails.com

Confreaks - http://www.confreaks.com

erubycon - http://erubycon.com

Lone Star Ruby Conference - http://lonestarrubyconf.com

Rails Konferenz - http://rails-konferenz.de

RailsConf - http://railsconf.com

Ruby Brigade - http://rubybrigade.org

Ruby Meetups - http://ruby.meetup.com

RubyConf - http://rubyconf.org

RubyKaigi - http://rubykaigi.org


Rich Morin has been programming computers since 1970, using a variety of languages and operating systems. He provides technical editing and writing, programming, and web development services, using (primarily) Ruby on Mac OS X.

 
AAPL
$98.15
Apple Inc.
-0.23
MSFT
$43.58
Microsoft Corpora
-0.31
GOOG
$587.42
Google Inc.
+1.81

MacTech Search:
Community Search:

Software Updates via MacUpdate

Knock 1.1.7 - Unlock your Mac by knockin...
Knock is a faster, safer way to sign in. You keep your iPhone with you all the time. Now you can use it as a password. You never have to open the app -- just knock on your phone twice, even when it's... Read more
Mellel 3.3.6 - Powerful word processor w...
Mellel is the leading word processor for OS X and has been widely considered the industry standard since its inception. Mellel focuses on writers and scholars for technical writing and multilingual... Read more
LibreOffice 4.3.0.4 - Free Open Source o...
LibreOffice is an office suite (word processor, spreadsheet, presentations, drawing tool) compatible with other major office suites. The Document Foundation is coordinating development and... Read more
Freeway Pro 7.0 - Drag-and-drop Web desi...
Freeway Pro lets you build websites with speed and precision... without writing a line of code! With it's user-oriented drag-and-drop interface, Freeway Pro helps you piece together the website of... Read more
Drive Genius 3.2.4 - Powerful system uti...
Drive Genius is an OS X utility designed to provide unsurpassed storage management. Featuring an easy-to-use interface, Drive Genius is packed with powerful tools such as a drive optimizer, a... Read more
Vitamin-R 2.15 - Personal productivity t...
Vitamin-R creates the optimal conditions for your brain to work at its best by structuring your work into short bursts of distraction-free, highly focused activity alternating with opportunities for... Read more
Toast Titanium 12.0 - The ultimate media...
Toast Titanium goes way beyond the very basic burning in the Mac OS and iLife software, and sets the standard for burning CDs, DVDs, and now Blu-ray discs on the Mac. Create superior sounding audio... Read more
OS X Yosemite Wallpaper 1.0 - Desktop im...
OS X Yosemite Wallpaper is the gorgeous new background image for Apple's upcoming OS X 10.10 Yosemite. This wallpaper is available for all screen resolutions with a source file that measures 5,418... Read more
Acorn 4.4 - Bitmap image editor. (Demo)
Acorn is a new image editor built with one goal in mind - simplicity. Fast, easy, and fluid, Acorn provides the options you'll need without any overhead. Acorn feels right, and won't drain your bank... Read more
Bartender 1.2.20 - Organize your menu ba...
Bartender lets you organize your menu bar apps. Features: Lets you tidy your menu bar apps how you want. See your menu bar apps when you want. Hide the apps you need to run, but do not need to... Read more

Latest Forum Discussions

See All

Murl the Squirrel (Games)
Murl the Squirrel 1.0 Device: iOS Universal Category: Games Price: $.99, Version: 1.0 (iTunes) Description: Meet Murl. He is teased by a group of flying squirrels because he can't fly. Determined to show them he's can fly, he meets... | Read more »
Celleste (Games)
Celleste 0.1 Device: iOS Universal Category: Games Price: $2.99, Version: 0.1 (iTunes) Description: Lots of cute action with amazing 3D graphics and a new type of gameplay! Take control over the forces of the universe to help a group... | Read more »
Super Heavy Sword (Games)
Super Heavy Sword 0.0.1 Device: iOS Universal Category: Games Price: $.99, Version: 0.0.1 (iTunes) Description: Get Ready to Get HEAVY! Monster Robot Studios presents SUPER Heavy Sword! The sequel to the smash hit HEAVY sword which... | Read more »
Angels In The Sky (Games)
Angels In The Sky 1.00 Device: iOS Universal Category: Games Price: $6.99, Version: 1.00 (iTunes) Description: - This game is only for the iPhone 5s. please do not use the iPad, iPhone 5 or earlier devices.- Just touch or holding... | Read more »
80 Days (Games)
80 Days 1.0.2 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0.2 (iTunes) Description: 1872, with a steampunk twist. Phileas Fogg has wagered he can circumnavigate the world in just eighty days. Choose your own route... | Read more »
Micromon (Games)
Micromon 1.0 Device: iOS Universal Category: Games Price: $.99, Version: 1.0 (iTunes) Description: 130+ Animated Monsters to Catch & Battle! No waiting, play at your own pace! Embark on an epic monster capture RPG like none... | Read more »
Empire Manager (Games)
Empire Manager 1.0 Device: iOS iPhone Category: Games Price: $3.99, Version: 1.0 (iTunes) Description: Become ruler of an empire. Manage your economy, develop technology, hire an army and conquer the world in this addictive turn-... | Read more »
Empire Manager HD (Games)
Empire Manager HD 1.0 Device: iOS Universal Category: Games Price: $7.99, Version: 1.0 (iTunes) Description: Become ruler of an empire. Manage your economy, develop technology, hire an army and conquer the world in this addictive... | Read more »
Star Admiral Review
Star Admiral Review By Rob Thomas on July 30th, 2014 Our Rating: :: ADMIRABLE ADMIRALSUniversal App - Designed for iPhone and iPad While this new digital CCG may feel a bit familiar, Star Admiral offers a sci-fi twist and galaxy’s... | Read more »
Zap! Pow! Become a Badass Wizard in Phan...
Zap! Pow! | Read more »

Price Scanner via MacPrices.net

iPad Cannibalization Threat “Overblown”
Seeking Alpha’s Kevin Greenhalgh observes that while many commentators think Apple’s forthcoming 5.5-inch panel iPhone 6 will cannibalize iPad sales, in his estimation, these concerns are being... Read more
Primate Labs Releases July 2014 MacBook Pro P...
Primate Labs’ John Poole has posted Geekbench 3 results for most of the new MacBook Pro models that Apple released on Tuesday. Poole observes that overall performance improvements for the new MacBook... Read more
Apple Re-Releases Bugfixed MacBook Air EFI Fi...
Apple has posted a bugfixed version EFI Firmware Update 2.9 a for MacBook Air (Mid 2011) models. The update addresses an issue where systems may take longer to wake from sleep than expected, and... Read more
Save $50 on the 2.5GHz Mac mini, plus free sh...
B&H Photo has the 2.5GHz Mac mini on sale for $549.99 including free shipping. That’s $50 off MSRP, and B&H will also include a free copy of Parallels Desktop software. NY sales tax only. Read more
Save up to $140 on an iPad Air with Apple ref...
Apple is offering Certified Refurbished iPad Airs for up to $140 off MSRP. Apple’s one-year warranty is included with each model, and shipping is free. Stock tends to come and go with some of these... Read more
$250 price drop on leftover 15-inch Retina Ma...
B&H Photo has dropped prices on 2013 15″ Retina MacBook Pros by $250 off original MSRP. Shipping is free, and B&H charges NY sales tax only: - 15″ 2.3GHz Retina MacBook Pro: $2249, $250 off... Read more
More iPad Upgrade Musings – The ‘Book Mystiqu...
Much discussed recently, what with Apple reporting iPad sales shrinkage over two consecutive quarters, is that it had apparently been widely assumed that tablet users would follow a two-year hardware... Read more
13-inch 2.5GHz MacBook Pro on sale for $999,...
Best Buy has the 13″ 2.5GHz MacBook Pro available for $999.99 on their online store. Choose free shipping or free instant local store pickup (if available). Their price is $100 off MSRP. Price is... Read more
Save up to $300 on an iMac with Apple refurbi...
The Apple Store has Apple Certified Refurbished iMacs available for up to $300 off the cost of new models. Apple’s one-year warranty is standard, and shipping is free. These are the best prices on... Read more
WaterField Unveils 15″ Outback Solo & 13″...
Hard on the heels of Apple’s refreshed MacBook Pro Retina laptops announcement, WaterField Designs has unveiled a 15-inch version of the waxed-canvas and leather Outback Solo and a 13-inch version of... Read more

Jobs Board

Sr. Product Leader, *Apple* Store Apps - Ap...
**Job Summary** Imagine what you could do here. At Apple , great ideas have a way of becoming great products, services, and customer experiences very quickly. Bring Read more
Sr Software Lead Engineer, *Apple* Online S...
Sr Software Lead Engineer, Apple Online Store Publishing Systems Keywords: Company: Apple Job Code: E3PCAK8MgYYkw Location (City or ZIP): Santa Clara Status: Full Read more
Sr Software Lead Engineer, *Apple* Online S...
Sr Software Lead Engineer, Apple Online Store Publishing Systems Keywords: Company: Apple Job Code: E3PCAK8MgYYkw Location (City or ZIP): Santa Clara Status: Full Read more
*Apple* Solutions Consultant (ASC) - Apple (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
Sr. Product Leader, *Apple* Store Apps - Ap...
**Job Summary** Imagine what you could do here. At Apple , great ideas have a way of becoming great products, services, and customer experiences very quickly. Bring Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.