Jello

Because everybody likes "paste & jello" sandwiches, right? I know I did when I was a kid.

Jello is a simple library to watch the OS X pasteboard and do something on every paste.

require 'jello'

Jello::Mould.new do |paste|
  system "say 'You pasted #{paste}'"
end

Jello.start!

For example, to watch for URLs copied, and then shorten the URL and replace the long URL with the shortened one, write a short mould like the following:

require 'open-uri'
require 'jello'

Jello::Mould.new do |paste|

  if paste =~ %r{^http://.*}
    uri = $&
    uri.gsub! /#/, '%23'
    unless uri =~ %r{^http://bit.ly}
      shortener = 'http://bit.ly/api?url=' + uri
      open(shortener).gets.chomp
    else
      nil
    end
  end
  
end

Jello.start! :verbose => true

Moulds can even be stacked:

require 'jello'

Jello::Mould.new do |paste|
  paste += '123'
end

Jello::Mould.new do |paste|
  paste += '456'
end

Jello.start! :verbose => true

Jello also provides a binary - if you have some moulds you use often, you can throw them in your ~/.jello/ folder (as .rb files), and then run jello with them:

# Assuming ~/.jello/ contains foo.rb, bar.rb, and gaz/{one,two}.rb
$ jello foo bar gaz
# Now foo.rb, bar.rb, one.rb, and two.rb would be executed on incoming
# pastes

You can also use pasteboards other than the general one (see man pbcopy for more information about this):

require 'jello'

Jello::Mould.new do |paste|
  paste.gsub! /abc/, 'def'
end

Jello.start!

Finally, you can create a Jello [property list][plist] for [launchd][] that will keep jello running all the time, even after you restart. Just run rake launchd from the Jello distribution directory. (This requires that you install the [LaunchDoctor][] gem first!)

[launchd]: <http://en.wikipedia.org/wiki/Launchd> "launchd on Wikipedia"
[plist]: <http://en.wikipedia.org/wiki/Property_list> "Property list on Wikipedia"
[LaunchDoctor]: <http://github.com/elliottcable/launchdr> "elliottcable's launchdr on GitHub"