Class: FFWD::CircularBuffer

Inherits:
Object
  • Object
show all
Defined in:
lib/ffwd/circular_buffer.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(capacity) ⇒ CircularBuffer

Returns a new instance of CircularBuffer.



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# File 'lib/ffwd/circular_buffer.rb', line 22

def initialize capacity
  @capacity = capacity
  @first = nil
  @last = nil
  @size = 0
end

Instance Attribute Details

#buffer ⇒ Object (readonly)

Returns the value of attribute buffer.



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# File 'lib/ffwd/circular_buffer.rb', line 20

def buffer
  @buffer
end

#capacity ⇒ Object (readonly)

Returns the value of attribute capacity.



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# File 'lib/ffwd/circular_buffer.rb', line 20

def capacity
  @capacity
end

#size ⇒ Object (readonly)

Returns the value of attribute size.



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# File 'lib/ffwd/circular_buffer.rb', line 20

def size
  @size
end

Instance Method Details

#<<(item) ⇒ Object 



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# File 'lib/ffwd/circular_buffer.rb', line 53

def << item
  node = Node.new(item, nil)

  if @last.nil?
    @first = @last = node
  else
    @last = @last.next = node
  end

  if @size >= @capacity
    @first = @first.next
  else
    @size += 1
  end
end

#clear ⇒ Object 



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# File 'lib/ffwd/circular_buffer.rb', line 29

def clear
  @first = nil
  @last = nil
  @size = 0
end

#each ⇒ Object 



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# File 'lib/ffwd/circular_buffer.rb', line 69

def each
  current = @first

  while not current.nil?
    yield current.value
    current = current.next
  end
end

#empty? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ffwd/circular_buffer.rb', line 35

def empty?
  size == 0
end

#peek ⇒ Object 



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# File 'lib/ffwd/circular_buffer.rb', line 39

def peek
  return nil if @first.nil?
  @first.value
end

#shift ⇒ Object 



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# File 'lib/ffwd/circular_buffer.rb', line 44

def shift
  return nil if @first.nil?
  value = @first.value
  @first = @first.next
  @last = nil if @first.nil?
  @size -= 1
  value
end