Class: Stream::ReversedStream

Inherits:
WrappedStream show all
Defined in:
lib/stream.rb

Overview

Each reversable stream (a stream that implements #backward and at_beginning?) can be wrapped by a ReversedStream.

A ReversedStream is created by the method #reverse:

(1..6).create_stream.reverse.to_a ==> [6, 5, 4, 3, 2, 1]

Instance Method Summary collapse

Constructor Details

#initialize(other_stream) ⇒ ReversedStream

Create a reversing wrapper for the reversable stream other_stream. If other_stream does not support backward moving a NotImplementedError is signaled on the first backward move.



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# File 'lib/stream.rb', line 421

def initialize(other_stream)
  super other_stream
  set_to_begin
end

Instance Method Details

#at_beginning? ⇒ Boolean

Returns true if the wrapped stream is at_end?.

Returns:

  • (Boolean) 


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# File 'lib/stream.rb', line 427

def at_beginning?
  wrapped_stream.at_end?
end

#at_end? ⇒ Boolean

Returns true if the wrapped stream is at_beginning?.

Returns:

  • (Boolean) 


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# File 'lib/stream.rb', line 432

def at_end?
  wrapped_stream.at_beginning?
end

#basic_backward ⇒ Object

Moves the wrapped stream one step forward.



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# File 'lib/stream.rb', line 442

def basic_backward
  wrapped_stream.basic_forward
end

#basic_forward ⇒ Object

Moves the wrapped stream one step backward.



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# File 'lib/stream.rb', line 437

def basic_forward
  wrapped_stream.basic_backward
end

#set_to_begin ⇒ Object

Sets the wrapped stream to the end.



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# File 'lib/stream.rb', line 452

def set_to_begin
  wrapped_stream.set_to_end
end

#set_to_end ⇒ Object

Sets the wrapped stream to the beginning.



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# File 'lib/stream.rb', line 447

def set_to_end
  wrapped_stream.set_to_begin
end