/usr/share/doc/ruby-concurrent/examples/a-tour-of-go-channels/range-and-close.rb is in ruby-concurrent 1.0.0-3.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
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$: << File.expand_path('../../../lib', __FILE__)
require 'concurrent-edge'
Channel = Concurrent::Channel
## A Tour of Go: Range and Close
# https://tour.golang.org/concurrency/4
def fibonacci(n, c)
x, y = 0, 1
(1..n).each do
c << x
x, y = y, x+y
end
c.close
end
c = Channel.new(capacity: 10)
Channel.go { fibonacci(c.capacity, c) }
c.each { |i| puts i }
__END__
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