ruby - 需要改进 ruby 正则表达式

Question

我想在字符串中查找相同模式两次。仅当与“and”连接时，但我似乎无法正确拉出第二场比赛

ruby-1.9.2-p290 :040 > text
 => "start a week and 2 days" 
ruby-1.9.2-p290 :041 > text.scan /[a\d] weeks?|months?|years? and [a\d] weeks?|months?|days?/
 => ["a week", "days"] 

我不明白为什么第二个匹配是“days”而不是“2 days”

如果我交换“a”和“2”，那么第二个匹配项仍然会排除该字符。

非常感谢任何帮助!

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阐明我的算法将是

如果字符串包含 x 个单位和 y 个单位，则 对 x 单位做某事 对 y 单位做某事结束

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我也试过

ruby-1.9.2-p290 :054 > text.scan /[a|\d] (weeks?|months?|years?) and [a|\d] (weeks?|months?|days?)/
 => [["week", "days"]] 
ruby-1.9.2-p290 :055 > text.scan /([a|\d] weeks?|months?|years?) and ([a|\d] weeks?|months?|days?)/
 => []

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作为实验，我尝试简化模式但没有成功改进

ruby-1.9.2-p290 :059 > text = "2 weeks and a day"
 => "2 weeks and a day" 
ruby-1.9.2-p290 :060 > text.scan /[a|\d] weeks?|months?|years?|days?/
 => ["2 weeks", "day"] 
ruby-1.9.2-p290 :061 > text = "a week and 2 days"
 => "a week and 2 days" 
ruby-1.9.2-p290 :062 > text.scan /[a|\d] weeks?|months?|years?|days?/
 => ["a week", "days"] 

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感谢所有做出贡献的人...

/([a\d] years?|[a\d] months?|[a\d] weeks?) and ([a\d] days?|[a\d] weeks?|[a\d] months?)/

符合我的要求，但我绝对有兴趣知道它是否可以减小尺寸...

ruby-1.9.2-p290 :077 > text = "2 weeks and a day"
 => "2 weeks and a day" 
ruby-1.9.2-p290 :078 > text.scan /([a\d] years?|[a\d] months?|[a\d] weeks?) and ([a\d] days?|[a\d] weeks?|[a\d] months?)/
 => [["2 weeks", "a day"]] 
ruby-1.9.2-p290 :079 > text = "2 weeks 2 days"
 => "2 weeks 2 days" 
ruby-1.9.2-p290 :080 > text.scan /([a\d] years?|[a\d] months?|[a\d] weeks?) teand ([a\d] days?|[a\d] weeks?|[a\d] months?)/
 => [] 

Answer 1

(a|\d) (weeks?|months?|years?) and (a|\d) (weeks?|months?|days?)