Class: FileQueue

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

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(file_name, delimiter = "\n") ⇒ FileQueue

Returns a new instance of FileQueue.



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# File 'lib/filequeue.rb', line 6

def initialize(file_name, delimiter="\n")
  @delimiter = delimiter
  @file_name = file_name
end

Instance Attribute Details

#delimiter ⇒ Object

Returns the value of attribute delimiter.



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# File 'lib/filequeue.rb', line 4

def delimiter
  @delimiter
end

#file_name ⇒ Object

Returns the value of attribute file_name.



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# File 'lib/filequeue.rb', line 4

def file_name
  @file_name
end

Instance Method Details

#clear ⇒ Object 



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# File 'lib/filequeue.rb', line 47

def clear
  safe_open 'w' do |file| end
end

#empty? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/filequeue.rb', line 43

def empty?
  return length == 0
end

#length ⇒ Object 



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# File 'lib/filequeue.rb', line 35

def length
  count = 0
  safe_open 'r' do |file|
    count = file.read.count @delimiter
  end
  count
end

#pop ⇒ Object 



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# File 'lib/filequeue.rb', line 22

def pop
  value = nil
  rest = nil
  safe_open 'r+' do |file|
    value = file.gets @delimiter
    rest = file.read
    file.rewind
    file.write rest
    file.truncate(file.pos)
  end
  value ? value[0..-(@delimiter.length) - 1] : nil
end

#push(obj) ⇒ Object Also known as: << 



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# File 'lib/filequeue.rb', line 11

def push(obj)
  if obj.match Regexp.new @delimiter
    raise "Queue objects cannot contain the queue delimiter"
  end
  safe_open 'a' do |file|
    file.write(obj + @delimiter)
  end
end