codegrinder

Will it grind ?

Yes, and in parallel !

codegrinder is a queue associated to one or several thread that share the same logic, and process the elements inserted into it.

How to install ?

gem install codegrinder

How to use ?

First, you have to require codegrinder:

require 'codegrinder'

Next, you have to build your codegrinder:

# That codegrinder print the square of any inserted value:
my_grinder = CodeGrinder.new { |i| print(String(i ** 2) + "\n") }

At last, you can start it:

# Starting the grinder with 4 threads. If no number is given, a single
# thread is used.
my_grinder.start(4)

From now on, any time you will insert a value in your grinder, it will be squared and printed to screen by one of your 4 threads.

Full example:

# Parallelized tiny pry-like implementation

STDOUT.sync = true
STDERR.sync = true

require 'codegrinder'

code_processor = CodeGrinder.new do |code|
  begin
    STDERR.write "  => #{eval(code).inspect}\n"
  rescue StandardError => e
    STDERR.write "  => #{e.class}: #{e.message}\n"
  end
end

code_processor.start(4)

QUIT = 'quit'

def self.next_command
  STDOUT.write("Enter command:\n")
  result = gets
  result.nil? ? QUIT : result.chomp
end

while (command = next_command) != QUIT
  code_processor << command
end

This small ruby shell can process up to 4 commands at the same time.