46 lines
1012 B
Ruby
46 lines
1012 B
Ruby
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# In software engineering, the composite pattern is a partitioning design
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# pattern. The composite pattern describes that a group of objects is to be
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# treated in the same way as a single instance of an object. The intent of a
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# composite is to "compose" objects into tree structures to represent part-whole
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# hierarchies. Implementing the composite pattern lets clients treat individual
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# objects and compositions uniformly
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# Tasks witch are used in composition
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class MonsterTask
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attr_reader :reward
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def initialize
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@reward = 100
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end
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end
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class PuzzleTask
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attr_reader :reward
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def initialize
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@reward = 200
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end
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end
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# Composer
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class Quest
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def initialize
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# Here we use Array as example of data structure for composition. Always is used Tree
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@tasks = []
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end
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def <<(task)
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@tasks << task
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end
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def reward
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@tasks.inject(0){ |sum, task| sum += task.reward }
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end
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end
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# Usage
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quest = Quest.new
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quest << MonsterTask.new
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quest << PuzzleTask.new
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puts quest.reward # => 300
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