ruby 字母数字排序未按预期工作

给定以下数组：

y = %w[A1 A2 B5 B12 A6 A8 B10 B3 B4 B8]
=> ["A1", "A2", "B5", "B12", "A6", "A8", "B10", "B3", "B4", "B8"]

预期的排序数组为：

=> ["A1", "A2", "A6", "A8", "B3", "B4", "B5", "B8", "B10", "B12"]

使用以下（普通）排序，我得到：

irb(main):2557:0> y.sort{|a,b| puts "%s <=> %s = %s\n" % [a, b, a <=> b]; a <=> b}
A1 <=> A8 = -1
A8 <=> B8 = -1
A2 <=> A8 = -1
B5 <=> A8 = 1
B4 <=> A8 = 1
B3 <=> A8 = 1
B10 <=> A8 = 1
B12 <=> A8 = 1
A6 <=> A8 = -1
A1 <=> A2 = -1
A2 <=> A6 = -1
B12 <=> B3 = -1
B3 <=> B8 = -1
B5 <=> B3 = 1
B4 <=> B3 = 1
B10 <=> B3 = -1  # this appears to be wrong, looks like 1 is being compared, not 10.
B12 <=> B10 = 1
B5 <=> B4 = 1
B4 <=> B8 = -1
B5 <=> B8 = -1
=> ["A1", "A2", "A6", "A8", "B10", "B12", "B3", "B4", "B5", "B8"]

……这显然不是我想要的。我知道我可以尝试先拆分 alpha，然后对数字进行排序，但似乎我不必这样做。

可能需要注意的是：我们现在只能使用 Ruby 1.8.7 :( 但即使 Ruby 2.0.0 也在做同样的事情。我在这里错过了什么？

建议？

您正在对字符串进行排序。字符串像字符串一样排序，而不是数字。如果您想对数字进行排序，那么您应该对数字进行排序，而不是对字符串进行排序。字符串'B10'按字典顺序小于字符串'B3'，这不是 Ruby 所独有的东西，甚至也不是编程所独有的东西，这就是按字典顺序对一段文本进行排序的方式几乎在任何地方都有效，在编程、数据库、词典、词典、电话簿等中。

您应该将字符串拆分为数字和非数字部分，并将数字部分转换为数字。数组排序是按字典顺序排序的，因此最终排序会完全正确：

y.sort_by {|s| # use `sort_by` for a keyed sort, not `sort`
  s.
    split(/(\d+)/). # split numeric parts from non-numeric
    map {|s| # the below parses numeric parts as decimals, ignores the rest
      begin Integer(s, 10); rescue ArgumentError; s end }}
#=> ["A1", "A2", "A6", "A8", "B3", "B4", "B5", "B8", "B10", "B12"]