Class: SlowEnumeratorTools::Merger::Iterator

Inherits:
Object
  • Object
show all
Defined in:
lib/slow_enumerator_tools/merger.rb

Constant Summary collapse

DONE = 
Object.new

Instance Method Summary collapse

Constructor Details

#initialize(enums) ⇒ Iterator

Returns a new instance of Iterator.



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# File 'lib/slow_enumerator_tools/merger.rb', line 16

def initialize(enums)
  @enums = enums
  @q = SizedQueue.new(5)
  @done = false
end

Instance Method Details

#next ⇒ Object

Raises:

  • (StopIteration) 


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# File 'lib/slow_enumerator_tools/merger.rb', line 22

def next
  raise StopIteration if @done

  nxt = @q.pop
  if DONE.equal?(nxt)
    @done = true
    raise StopIteration
  else
    nxt
  end
end

#start ⇒ Object 



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# File 'lib/slow_enumerator_tools/merger.rb', line 34

def start
  threads = @enums.map { |enum| spawn_empty_into(enum, @q) }

  spawn do
    threads.each(&:join)
    @q << DONE
  end
end