threach

threach adds to the Enumerable module to provide a threaded version of whatever enumerator you throw at it (each by default).

Use

# You like #each? You'll love...err..probably like #threach
require 'rubygems'
require 'threach'

# Process with 2 threads. It assumes you want 'each'
# as your iterator.
(1..10).threach(2) {|i| puts i.to_s}  

# You can also specify the iterator
File.open('mybigfile') do |f|
  f.threach(2, :each_line) do |line|
    processLine(line)
  end
end

# threach does not care what the arity of your block is
# as long as it matches the iterator you ask for

('A'..'Z').threach(3, :each_with_index) do |letter, index|
  puts "#{index}: #{letter}"
end

# Or with a hash
h = {'a' => 1, 'b'=>2, 'c'=>3}
h.threach(2) do |letter, i|
  puts "#{i}: #{letter}"
end

Why and when to use it?

Well, if you're using stock (MRI) ruby -- you probably shouldn't bother with threach. It'll just slow things down. But if you're using a ruby implementation that has real threads, like JRuby, this will give you relatively painless multi-threading.

You can always do something like:

if defined? JRUBY_VERSION
  numthreads = 3
else
  numthreads = 0
end

my_enumerable.threach(numthreads) {|i| ...}

Note the "relatively" in front of "painless" up there. The block you pass still has to be thread-safe, and there are many data structures you'll encounter that are not thread-safe. Scalars, arrays, and hashes are, though, under JRuby, and that'll get you pretty far.

Note on Patches/Pull Requests

Fork the project.
Make your feature addition or bug fix.
Add tests for it. This is important so I don't break it in a future version unintentionally.
Commit, do not mess with rakefile, version, or history. (if you want to have your own version, that is fine but bump version in a commit by itself I can ignore when I pull)
Send me a pull request. Bonus points for topic branches.

threach

Use

Why and when to use it?

Note on Patches/Pull Requests

Copyright