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.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Skype 8.52.0.138 - Voice-over-internet p...
Skype allows you to talk to friends, family and co-workers across the Internet without the inconvenience of long distance telephone charges. Using peer-to-peer data transmission technology, Skype... Read more
Bookends 13.2.6 - Reference management a...
Bookends is a full-featured bibliography/reference and information-management system for students and professionals. Bookends uses the cloud to sync reference libraries on all the Macs you use.... Read more
BusyContacts 1.4.0 - Fast, efficient con...
BusyContacts is a contact manager for OS X that makes creating, finding, and managing contacts faster and more efficient. It brings to contact management the same power, flexibility, and sharing... Read more
Chromium 77.0.3865.75 - Fast and stable...
Chromium is an open-source browser project that aims to build a safer, faster, and more stable way for all Internet users to experience the web. Version 77.0.3865.75: A list of changes is available... Read more
DiskCatalogMaker 7.5.5 - Catalog your di...
DiskCatalogMaker is a simple disk management tool which catalogs disks. Simple, light-weight, and fast Finder-like intuitive look and feel Super-fast search algorithm Can compress catalog data for... Read more
Alfred 4.0.4 - Quick launcher for apps a...
Alfred is an award-winning productivity application for OS X. Alfred saves you time when you search for files online or on your Mac. Be more productive with hotkeys, keywords, and file actions at... Read more
A Better Finder Rename 10.45 - File, pho...
A Better Finder Rename is the most complete renaming solution available on the market today. That's why, since 1996, tens of thousands of hobbyists, professionals and businesses depend on A Better... Read more
iFinance 4.5.11 - Comprehensively manage...
iFinance allows you to keep track of your income and spending -- from your lunchbreak coffee to your new car -- in the most convenient and fastest way. Clearly arranged transaction lists of all your... Read more
OmniGraffle Pro 7.11.3 - Create diagrams...
OmniGraffle Pro helps you draw beautiful diagrams, family trees, flow charts, org charts, layouts, and (mathematically speaking) any other directed or non-directed graphs. We've had people use... Read more
BBEdit 12.6.7 - Powerful text and HTML e...
BBEdit is the leading professional HTML and text editor for the Mac. Specifically crafted in response to the needs of Web authors and software developers, this award-winning product provides a... Read more

Latest Forum Discussions

See All

Five Nights at Freddy's AR: Special...
Five Nights at Freddy's AR: Special Delivery is a terrifying new nightmare from developer Illumix. Last week, FNAF fans were sent into a frenzy by a short teaser for what we now know to be Special Delivery. Those in the comments were quick to... | Read more »
Rush Rally 3's new live events are...
Last week, Rush Rally 3 got updated with live events, and it’s one of the best things to happen to racing games on mobile. Prior to this update, the game already had multiplayer, but live events are more convenient in the sense that it’s somewhat... | Read more »
Why your free-to-play racer sucks
It’s been this way for a while now, but playing Hot Wheels Infinite Loop really highlights a big issue with free-to-play mobile racing games: They suck. It doesn’t matter if you’re trying going for realism, cart racing, or arcade nonsense, they’re... | Read more »
Steam Link Spotlight - The Banner Saga 3
Steam Link Spotlight is a new feature where we take a look at PC games that play exceptionally well using the Steam Link app. Our last entry talked about Terry Cavanaugh’s incredible Dicey Dungeons. Read about how it’s a great mobile experience... | Read more »
PSA: GRIS has some issues
You may or may not have seen that Devolver Digital just released GRIS on the App Store, but we wanted to do a quick public service announcement to say that you might not want to hop on buying it just yet. The puzzle platformer has come to small... | Read more »
Explore the world around you in new matc...
Got a hankering for a fresh-feeling Match-3 puzzle game that offers a unique twist? You might find exactly what you’re looking for with What a Wonderful World, a new spin on the classic mobile genre which merges entertaining puzzles with global... | Read more »
Combo Quest (Games)
Combo Quest 1.0 Device: iOS Universal Category: Games Price: $.99, Version: 1.0 (iTunes) Description: Combo Quest is an epic, time tap role-playing adventure. In this unique masterpiece, you are a knight on a heroic quest to retrieve... | Read more »
Hero Emblems (Games)
Hero Emblems 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: ** 25% OFF for a limited time to celebrate the release ** ** Note for iPhone 6 user: If it doesn't run fullscreen on your device... | Read more »
Puzzle Blitz (Games)
Puzzle Blitz 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: Puzzle Blitz is a frantic puzzle solving race against the clock! Solve as many puzzles as you can, before time runs out! You have... | Read more »
Sky Patrol (Games)
Sky Patrol 1.0.1 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0.1 (iTunes) Description: 'Strategic Twist On The Classic Shooter Genre' - Indie Game Mag... | Read more »

Price Scanner via MacPrices.net

Save $150-$250 on 10.2″ WiFi + Cellular iPads...
Verizon is offering $150-$250 discounts on Apple’s new 10.2″ WiFi + Cellular iPad with service. Buy the iPad itself and save $150. Save $250 on the purchase of an iPad along with an iPhone. The fine... Read more
Apple continues to offer 13″ 2.3GHz Dual-Core...
Apple has Certified Refurbished 2017 13″ 2.3GHz Dual-Core non-Touch Bar MacBook Pros available starting at $1019. An standard Apple one-year warranty is included with each model, outer cases are new... Read more
Apple restocks 2018 MacBook Airs, Certified R...
Apple has restocked Certified Refurbished 2018 13″ MacBook Airs starting at only $849. Each MacBook features a new outer case, comes with a standard Apple one-year warranty, and is shipped free. The... Read more
Sunday Sale! 2019 27″ 5K 6-Core iMacs for $20...
B&H Photo has the new 2019 27″ 5K 6-Core iMacs on stock today and on sale for up to $250 off Apple’s MSRP. Overnight shipping is free to many locations in the US. These are the same iMacs sold by... Read more
Weekend Sale! 2019 13″ MacBook Airs for $200...
Amazon has new 2019 13″ MacBook Airs on sale for $200 off Apple’s MSRP, with prices starting at $899, each including free shipping. Be sure to select Amazon as the seller during checkout, rather than... Read more
2019 15″ MacBook Pros now on sale for $350-$4...
B&H Photo has Apple’s 2019 15″ 6-Core and 8-Core MacBook Pros on sale today for $350-$400 off MSRP, starting at $2049, with free overnight shipping available to many addresses in the US: – 2019... Read more
Buy one Apple Watch Series 5 at Verizon, get...
Buy one Apple Watch Series 5 at Verizon, and get a second Watch for 50% off. Plus save $10 on your first month of service. The fine print: “Buy Apple Watch, get another up to 50% off on us. Plus $10... Read more
Sprint offers 64GB iPhone 11 for free to new...
Sprint will include the 64GB iPhone 11 for free for new customers with an eligible trade-in in of the iPhone 7 or newer through September 19, 2019. The fine print: “iPhone 11 64GB $0/mo. iPhone 11... Read more
Verizon offers new iPhone 11 models for up to...
Verizon is offering Apple’s new iPhone 11 models for $500 off MSRP to new customers with an eligible trade-in (see list below). Discount is applied via monthly bill credits over 24 months. Verizon is... Read more
AT&T offers free $300 reward card + free...
AT&T Wireless will include a second free 64GB iPhone 11 with the purchase of one eligible iPhone at full price. They will also include a free $300 rewards card. The fine print: “Buy an elig.... Read more

Jobs Board

Student Employment (Blue *Apple* Cafe) Spri...
Student Employment (Blue Apple Cafe) Spring 2019 Penn State University Campus/Location: Penn State Brandywine Campus City: Media, PA Date Announced: 12/20/2018 Date Read more
Best Buy *Apple* Computing Master - Best Bu...
**732359BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Store Associates **Location Number:** 000171-Winchester Road-Store **Job Description:** Read more
*Apple* Mobile Master - Best Buy (United Sta...
**732324BR** **Job Title:** Apple Mobile Master **Job Category:** Store Associates **Location Number:** 000013-Fargo-Store **Job Description:** **What does a Best Read more
Best Buy *Apple* Computing Master - Best Bu...
**732455BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Sales **Location Number:** 000449-Auburn Hills-Store **Job Description:** **What does a Read more
*Apple* Mobility Pro - Best Buy (United Stat...
**732490BR** **Job Title:** Apple Mobility Pro **Job Category:** Store Associates **Location Number:** 000449-Auburn Hills-Store **Job Description:** At Best Buy, Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.