35 lines
705 B
Ruby
35 lines
705 B
Ruby
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module Gitlab
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# A class that can be wrapped around an expensive method call so it's only
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# executed when actually needed.
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#
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# Usage:
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#
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# object = Gitlab::Lazy.new { some_expensive_work_here }
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#
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# object['foo']
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# object.bar
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class Lazy < BasicObject
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def initialize(&block)
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@block = block
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end
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def method_missing(name, *args, &block)
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__evaluate__
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@result.__send__(name, *args, &block)
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end
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def respond_to_missing?(name, include_private = false)
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__evaluate__
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@result.respond_to?(name, include_private) || super
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end
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private
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def __evaluate__
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@result = @block.call unless defined?(@result)
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end
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end
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end
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