Scala:将String与Regex列表进行匹配

Question

我有一个字符串,说var str = "hello, world"和List的Regex模式

val patterns = List(new Regex("hello, (.*)", "substr"), new Regex("hi, (.*)", "substr"))

我如何匹配str这些模式？现在,List我没有使用模式,而是执行以下操作:

val pattern1 = new Regex("hello, (.*)", "substr")
val pattern2 = new Regex("hi, (.*)", "substr")
var someVar = "something"
var someVar2 = "something else"
str match {
    case pattern1(substr) => { someVar = substr; someVar2 = "someValue" }
    case pattern2(substr) => { someVar = substr; someVar2 = "someOtherValue" }

}

附录:

我忘了提一件重要的事情:实际上有几个模式列表.并且someVar2取决于发生第一个模式匹配的列表而取其值.对我来说,无论是使用嵌套列表List(List(new Regex(...), new Regex(...), ...), List(new Regex(...), new Regex(...), ...))还是val对每个模式列表使用单独的列表都没关系val patterns1 = List(new Regex(...), ...); val patterns2 = List(new Regex(...), ...).

Answer 1

试试这个:

scala> patterns.collectFirst{ p => str match { case p(substr) => substr } }
res3: Option[String] = Some(world)

scala> val str2 = "hi, Fred"
str2: String = hi, Fred

scala> patterns.collectFirst{ p => str2 match { case p(substr) => substr } }
res4: Option[String] = Some(Fred)

编辑:更新以考虑更改的要求...

鉴于:

val patternMapping = Map(("marker1" -> patterns), ("marker2" -> patterns2), ...)

你应该能够嵌套collectFirst调用,结果是这样的:

scala> patternMapping.collectFirst{ case (mark, pList) => pList.collectFirst{ p => str match { case p(substr) => (mark -> substr) } } }.flatten
res5: Option[(String, String)] = Some((marker1,world))

我怀疑这可能会被玩弄和整理,但应该给出一般的想法.