MacRuby is a Ruby implementation for Mac OS X that allows Ruby code to be compiled to native machine code. It uses the LLVM compiler infrastructure and integrates tightly with Cocoa and Objective-C. Some key features include using the same syntax as Ruby but with faster performance due to compilation, ability to build Mac desktop applications that can be submitted to the Mac App Store, and direct access to technologies like Grand Central Dispatch for concurrent programming. The future of MacRuby may involve continued integration of Ruby with technologies like LLVM and GCD.
1. MacRuby
What is it?
and why should you care?
Presented by: Joshua Ballanco
2. A bit about me...
• Using Ruby since 2004 (didn’t discover
Rails until 2006)
• Worked for Apple 2006-2010 (Fifth Ave
store & HQ in Cupertino)
• Now at Patch (just completed a migration
to Ruby 1.9)
• MacRuby Core Team member
3. Overview
• Practical MacRuby
• How is MacRuby different?
• Working with Cocoa
• Compiled Ruby!
• Make your millions on the App store
• Nuts & Bolts
• GC
• Regular Expression Engine
• Hash method syntax
• LLVM & other Hacking
• GCD
8. What is MacRuby?
• http://www.macruby.org
• http://www.macruby.org/files/
• http://www.macruby.org/files/nightlies/
• Available from RVM (but not recommended)
• Source now located at GitHub!
https://github.com/MacRuby/MacRuby
9. What is MacRuby?
• Compiling MacRuby:
• Need LLVM (see the README; brew install llvm)
• rake ; sudo rake install
• Bugs – https://www.macruby.org/trac/report
• MacRuby-devel mailing list
• @macruby, #macruby
11. No Really, What is
MacRuby?
A language with:
• Dynamic typing
• Objects everywhere
• Method calls via sending messages
• Automatic generation of accessors
• Methods can be added to classes at runtime
• Garbage Collection
• Closures
12. No Really, What is
MacRuby?
A language with:
• Dynamic typing
• Objects everywhere
• Method calls via sending messages
• Automatic generation of accessors
• Methods can be added to classes at runtime
• Garbage Collection
• Closures
...called Objective-C
20. Integrating with Cocoa
• Bridge Support (please download preview 3
from the “files” page)
• gen_bridge_metadata reads header files
and generates XML descriptions of types
and method signatures
• MacRuby uses BS files to construct calls
and access constants and types
• framework “Foundation”
21. Integrating with Cocoa
• String, Array, Hash, are members of the
NSString, NSArray, and NSDictionary class
clusters
• Caution: NSString, NSArray, and
NSDictionary will lie to you!
• Time is implemented as a subclass of
NSDate
23. A Ruby You Can
Compile
• macrubyc
• Advantages:
• Faster startup, faster runtime (in most cases)
• Don’t distribute the source!
• Disadvantages:
• ?
• ...some bugs
24. A Ruby You Can
Compile
• -c → Compile and assemble; good for
multistage builds
• -C → Compile, assemble, and link creating
an *.rbo
• Can also create stand-alone executables
and entire “*.framework”s (experimental)
26. I wanna be an App
store billionaire...
• Downloads contain Xcode templates
(mostly work in Xcode 4)
• Integration with Interface Builder
• macruby_deploy
• Includes BS files
• Unpacks Gems
• Compiles source
30. Garbage Collector:
libauto
• Yet another open source project from
Apple
• The GC for Obj-C
• Based on write barriers
• scanning, conservative, generational, multi-
threaded garbage collector...
• ...unfortunately...slow
31. Garbage Collector:
the Next Generation(?)
• Ruby does A LOT of allocations
• Nice to not have to stop the world, but...
• Write barriers are slow
• Maybe ref counting?
• Maybe MRI’s collector isn’t so bad after all...
32. RegExps:
ICU
• Oniguruma is not (real thread) thread safe
• ICU is
• thread safe
• Unicode compatible
• not as crazy feature-full as Oniguruma
• There are some bugs...but honestly, stop
doing that with RegExps!!!
33. Hash method syntax
• Ruby 1.9’s hash syntax with Symbol keys:
a = { foo: 1, bar: 2, baz: “Hello, world” }
• ...looks a bit like:
[@”Hello, world” rangeOfString:@”ello”
options: NSCaseInsensitiveSearch]
• Let’s go with that!
34. Hash method syntax
• MacRuby turns method calls with hash
arguments into SEL
• MacRuby turns method definitions with
hash lists into SEL
• MacRuby can call Objective-C
• Objective-C can call MacRuby, but when
possible you should use:
[[MacRuby sharedRuntime]
performRubySelector:@”foo”]
35. LLVM, JIT, and Hacking
• LLVM provides optimizations
• LLVM provides JIT utilities (kinda slow)
• MacRuby can emit LLVM...
VM_DUMP_IR=1 macruby -e "def foo; puts
'hello'; end; foo"
• Find other neat tricks in HACKING.rdoc
38. GCD
• MacRuby can tap directly into GCD
• Dispatch module:
• Dispatch::Queue
• Dispatch::Group
• Dispatch::Source
• Dispatch Gem too!
39. GCD
• Dispatch is a powerful tool for concurrent
programming
• Example: ControlTower
• MacRuby Rack-based server
• Uses GCD to handle requets
• Accomplishes in 1 line what takes Thin/
EventMachine > 6000 lines of C++ &
Ruby
41. GCD
• Can we make GCD work in MRI?
• JRuby thinks they can make it work...
https://github.com/headius/jcd
• GCD is Multithreaded Programming, Ruby
Style
42. Who Is MacRuby?
• Laurent Sansonetti • Watson
• Vincent Isambart • Takao Kouji
• Eloy Durán • Mark Rada
• Matt Aimonetti • You?
• Joshua Ballanco
• Thibault Martin-
Lagardette
