Executing Objective-C from Ruby on Rails

Question

I want to execute the following Objective-C code in my Rails application:

CFMutableStringRef inputString = CFStringCreateMutableCopy(kCFAllocatorDefault, 32,     CFSTR("общей"));
CFLocaleRef locale = CFLocaleCreate(kCFAllocatorDefault, CFSTR("ru"));

CFStringTransform(inputString, NULL, kCFStringTransformStripDiacritics, false);
CFStringLowercase(inputString, locale);


NSLog(@"%@", (NSString *)inputString);

CFRelease(locale);
CFRelease(inputString);

It basically outputs a lowercase, diacritics-free version of the input string. I am running on a Snow Leopard server.

How can I do this (without using MacRuby, which seems to be an overkill here)? I've heard of Ruby extensions but can't find any resources in my case.

This really seems more like a pure Ruby question: "how do I strip diacritics from a string?". Answer: stackoverflow.com/questions/225471/… — rob mayoff
– rob mayoff, Commented Nov 17, 2011 at 2:01
Unfortunately, it's not that simple... I need to use the native Objective-C functions because I'm dealing with non-latin strings too (Hindi, Mandarin, Russian, etc.). — alste
– alste, Commented Nov 17, 2011 at 2:14
@alste: Somewhat pedantic, but there's no Objective-C in the above. You're using constants and functions from Core Foundation, which is a C library. Anyway, can Rails call out to a binary located on the filesystem? If so, make the above its own little utility, then call out to it as needed, passing the input string as an argument. Note that if you do that, remember not to use NSLog() because it's so noisy. — lowell
– lowell, Commented Nov 17, 2011 at 2:34
Thanks for your input. I've considered that, but I would have to call the binary thousands of times (when inserting new foreign words into a database, for example - I would want to store their lowercase/diacritics-free version). Is there a more native way to call Core Foundation functions from within Ruby? — alste
– alste, Commented Nov 17, 2011 at 3:28
Also, Ruby (especially 1.9) can deal with non-Latin characters quite well. You probably don't need Obj-C at all here. — Marnen Laibow-Koser
– Marnen Laibow-Koser, Commented Nov 17, 2011 at 14:55

rob mayoff · Accepted Answer · 2011-11-17 05:50:51Z

1

You can probably do it using ffi, but it'll require entering a bunch of function specs. Tiny test case for calling a Core Foundation function:

require 'ffi'

module CF
  extend FFI::Library
  ffi_lib '/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation'
  attach_function :CFAbsoluteTimeGetCurrent, [], :double
end

puts CF.CFAbsoluteTimeGetCurrent

answered Nov 17, 2011 at 5:50

rob mayoff

387k69 gold badges842 silver badges887 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Francisco Soto · Accepted Answer · 2011-11-17 05:32:58Z

0

Instead of creating an app you need to be spawning on and off in a single Rails instance you can write your app using other ways for communication, like named pipes:

http://hints.macworld.com/article.php?story=20041025103920992 http://www.pauldix.net/2009/07/using-named-pipes-in-ruby-for-interprocess-communication.html

Or going the Ruby C extensions way:

http://ruby-doc.org/docs/ProgrammingRuby/html/ext_ruby.html http://people.apache.org/~rooneg/talks/ruby-extensions/ruby-extensions.html

answered Nov 17, 2011 at 5:32

Francisco Soto

10.4k2 gold badges40 silver badges46 bronze badges

1 Comment

alste Over a year ago

ruby extensions is the way to go

Collectives™ on Stack Overflow

Executing Objective-C from Ruby on Rails

2 Answers 2

Comments

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related