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59 lines
841 B
Ruby
59 lines
841 B
Ruby
# This file contains the Ruby code from book of
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# "Data Structures and Algorithms
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# with Object-Oriented Design Patterns in Ruby"
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# by Bruno R. Preiss.
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#
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# Copyright (c) 2004 by Bruno R. Preiss, P.Eng. All rights reserved.
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class Container < AbstractObject
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include ::Enumerable
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def initialize
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super
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@count = 0
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end
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attr_reader :count
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def purge
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@count = 0
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end
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def empty?
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count == 0
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end
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def full?
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false
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end
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abstractmethod :iter
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def each
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i = iter
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while i.more?
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yield i.succ
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end
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end
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def to_s
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s = ""
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each do |obj|
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s << ", " if not s.empty?
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s << obj.to_s
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end
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type.name + "{" + s + "}"
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end
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def accept(visitor)
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assert { visitor.is_a?(Visitor) }
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each do |obj|
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break if visitor.done?
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visitor.visit(obj)
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end
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end
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end
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