22 lines
199 B
Ruby
22 lines
199 B
Ruby
class Numeric
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def zero?
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self == 0
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end
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def nonzero?
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if self == 0
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nil
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else
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self
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end
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end
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def positive?
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self > 0
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end
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def negative?
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self < 0
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end
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end
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