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Again, just an example of Ruby’s flexibility.

 class IO
   def | proc
     proc[self]
   end
 end

Pass a File or Socket through a chain of procs with a pipe!

 wc = proc { |io| io.inject(0) { |i, line| i += 1 } }

Like the above proc, which counts lines in a file.

 count = open("/var/log/messages") | wc

Now, if you want to keep going and get these procs all chained together into a nice series of pipes and ongoing IO, see:

 wc = proc { |io| IO[io.inject(0) { |i, line| i += 1 }] }
 grep = proc { |exp| proc { |io| IO[io.grep(exp)] } }

 count = open("/var/log/messages") | grep[/root/] | wc
 p count.read

Which can be done in a myriad of fashions, but I chose to use StringIO in my script: ruby-pipe.rb. What fun. See Symbol.to_proc for a like kind of wonderment.