/usr/share/doc/ is in ruby-concurrent 1.0.0-3.
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/usr/share/doc/ruby-concurrent/
/usr/share/doc/ruby-concurrent/README.md.gz
/usr/share/doc/ruby-concurrent/changelog.Debian.gz
/usr/share/doc/ruby-concurrent/changelog.gz
/usr/share/doc/ruby-concurrent/copyright
/usr/share/doc/ruby-concurrent/examples/
/usr/share/doc/ruby-concurrent/examples/a-tour-of-go-channels/
/usr/share/doc/ruby-concurrent/examples/a-tour-of-go-channels/buffered-channels.rb
/usr/share/doc/ruby-concurrent/examples/a-tour-of-go-channels/channels.rb
/usr/share/doc/ruby-concurrent/examples/a-tour-of-go-channels/default-selection.rb
/usr/share/doc/ruby-concurrent/examples/a-tour-of-go-channels/equivalent-binary-trees.rb
/usr/share/doc/ruby-concurrent/examples/a-tour-of-go-channels/range-and-close.rb
/usr/share/doc/ruby-concurrent/examples/a-tour-of-go-channels/select.rb
/usr/share/doc/ruby-concurrent/examples/actor_stress_test.rb
/usr/share/doc/ruby-concurrent/examples/atomic_example.rb
/usr/share/doc/ruby-concurrent/examples/benchmark_async.rb
/usr/share/doc/ruby-concurrent/examples/benchmark_atomic.rb
/usr/share/doc/ruby-concurrent/examples/benchmark_atomic_1.rb
/usr/share/doc/ruby-concurrent/examples/benchmark_atomic_boolean.rb
/usr/share/doc/ruby-concurrent/examples/benchmark_atomic_fixnum.rb
/usr/share/doc/ruby-concurrent/examples/benchmark_map.rb
/usr/share/doc/ruby-concurrent/examples/benchmark_new_futures.rb
/usr/share/doc/ruby-concurrent/examples/benchmark_read_write_lock.rb
/usr/share/doc/ruby-concurrent/examples/benchmark_structs.rb
/usr/share/doc/ruby-concurrent/examples/benchmark_thread_pool_implementations.rb
/usr/share/doc/ruby-concurrent/examples/edge_futures.in.rb
/usr/share/doc/ruby-concurrent/examples/edge_futures.out.rb
/usr/share/doc/ruby-concurrent/examples/format.rb
/usr/share/doc/ruby-concurrent/examples/go-by-example-channels/
/usr/share/doc/ruby-concurrent/examples/go-by-example-channels/channel-buffering.rb
/usr/share/doc/ruby-concurrent/examples/go-by-example-channels/channel-directions.rb
/usr/share/doc/ruby-concurrent/examples/go-by-example-channels/channel-synchronization.rb
/usr/share/doc/ruby-concurrent/examples/go-by-example-channels/channels.rb
/usr/share/doc/ruby-concurrent/examples/go-by-example-channels/closing-channels.rb
/usr/share/doc/ruby-concurrent/examples/go-by-example-channels/non-blocking-channel-operations.rb
/usr/share/doc/ruby-concurrent/examples/go-by-example-channels/range-over-channels.rb
/usr/share/doc/ruby-concurrent/examples/go-by-example-channels/rate-limiting.rb
/usr/share/doc/ruby-concurrent/examples/go-by-example-channels/select.rb
/usr/share/doc/ruby-concurrent/examples/go-by-example-channels/ticker.rb
/usr/share/doc/ruby-concurrent/examples/go-by-example-channels/timeouts.rb
/usr/share/doc/ruby-concurrent/examples/go-by-example-channels/timers.rb
/usr/share/doc/ruby-concurrent/examples/go-by-example-channels/worker-pools.rb
/usr/share/doc/ruby-concurrent/examples/graph_atomic_bench.rb
/usr/share/doc/ruby-concurrent/examples/init.rb
/usr/share/doc/ruby-concurrent/examples/stress_ruby_thread_pool.rb
/usr/share/doc/ruby-concurrent/examples/thread_local_memory_usage.rb
/usr/share/doc/ruby-concurrent/examples/thread_local_var_bench.rb
/usr/share/doc/ruby-concurrent/examples/who.rb