Class: CouchShell::RingBuffer

Inherits:
Object
  • Object
show all
Defined in:
lib/couch-shell/ring_buffer.rb

Overview

Not threadsafe!

Defined Under Namespace

Classes: UninitializedAccess

Instance Method Summary collapse

Constructor Details

#initialize(size) ⇒ RingBuffer

Returns a new instance of RingBuffer.



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# File 'lib/couch-shell/ring_buffer.rb', line 22

def initialize(size)
  @ary = Array.new(size, nil)
  @index = nil
  @written = 0
end

Instance Method Details

#<<(elem) ⇒ Object 



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# File 'lib/couch-shell/ring_buffer.rb', line 73

def <<(elem)
  if @index.nil? || @index == size - 1
    @index = 0
  else
    @index += 1
  end
  @ary[@index] = elem
  if @written < @index + 1
    @written = @index + 1
  end
end

#[](i) ⇒ Object 



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# File 'lib/couch-shell/ring_buffer.rb', line 65

def [](i)
  i = i.to_int
  if i >= @written
    raise UninitializedAccess.new(i)
  end
  @ary[i]
end

#current ⇒ Object 



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# File 'lib/couch-shell/ring_buffer.rb', line 40

def current
  if @index.nil?
    if block_given?
      nil
    else
      raise UninitializedAccess.new(0)
    end
  else
    if block_given?
      yield @ary[index]
    else
      @ary[index]
    end
  end
end

#empty? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/couch-shell/ring_buffer.rb', line 36

def empty?
  @written == 0
end

#index ⇒ Object

index of current (last written) element, or nil if empty



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# File 'lib/couch-shell/ring_buffer.rb', line 61

def index
  @index
end

#initialized_size ⇒ Object 



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# File 'lib/couch-shell/ring_buffer.rb', line 32

def initialized_size
  @written
end

#readable_index?(i) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/couch-shell/ring_buffer.rb', line 56

def readable_index?(i)
  i >= 0 && i < @written
end

#size ⇒ Object 



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# File 'lib/couch-shell/ring_buffer.rb', line 28

def size
  @ary.size
end