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Here's a small ruby script:

p "ruby #{ RUBY_VERSION }p#{ RUBY_PATCHLEVEL }"
p 100.times.collect{|i| i}.sort_by{|j| j % 1}

I would have expect the same result from a version to another. In my case, it's not. Here's the results

"ruby 2.2.3p173"
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99

"ruby 2.3.1p112"
[99, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 0]

Is that normal?

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2 回答 2

2

如果项目相同，Ruby 不保证您的排序顺序。

至于为什么不同版本的结果会发生变化，这看起来是一个相关的变化：ruby 2.3 在比以前更多的情况下尝试使用 c 标准库提供的快速排序实现。

于 2016-05-24T13:17:18.477 回答
1

看看Ruby 中的排序是否稳定？. 快速回答是否定的，不是。这意味着如果两个值相等，在您的情况下始终等于 0，则您无法对它们相对于彼此的去向做出任何假设。

于 2016-05-24T13:11:22.300 回答