访问Scala Parser正则表达式匹配数据
发布时间:2020-12-16 09:01:57 所属栏目:安全 来源:网络整理
导读:我想知道是否可以从下面的语法中获得匹配正则表达式生成的MatchData. object DateParser extends JavaTokenParsers { .... val dateLiteral = """(d{4}[-/])?(dd[-/])?(dd)""".r ^^ { ... get MatchData }} 一个选项当然是在块内再次执行匹配,但是由于R
我想知道是否可以从下面的语法中获得匹配正则表达式生成的MatchData.
object DateParser extends JavaTokenParsers { .... val dateLiteral = """(d{4}[-/])?(dd[-/])?(dd)""".r ^^ { ... get MatchData } } 一个选项当然是在块内再次执行匹配,但是由于RegexParser已经执行了匹配,我希望它将MatchData传递给块,或者存储它? 解决方法
这是将您的正则表达式转换为解析器的隐式定义:
/** A parser that matches a regex string */ implicit def regex(r: Regex): Parser[String] = new Parser[String] { def apply(in: Input) = { val source = in.source val offset = in.offset val start = handleWhiteSpace(source,offset) (r findPrefixMatchOf (source.subSequence(start,source.length))) match { case Some(matched) => Success(source.subSequence(start,start + matched.end).toString,in.drop(start + matched.end - offset)) case None => Failure("string matching regex `"+r+"' expected but `"+in.first+"' found",in.drop(start - offset)) } } } 只是适应它: object X extends RegexParsers { /** A parser that matches a regex string and returns the Match */ def regexMatch(r: Regex): Parser[Regex.Match] = new Parser[Regex.Match] { def apply(in: Input) = { val source = in.source val offset = in.offset val start = handleWhiteSpace(source,source.length))) match { case Some(matched) => Success(matched,in.drop(start - offset)) } } } val t = regexMatch("""(dd)/(dd)/(dddd)""".r) ^^ { case m => (m.group(1),m.group(2),m.group(3)) } } 例: scala> X.parseAll(X.t,"23/03/1971") res8: X.ParseResult[(String,String,String)] = [1.11] parsed: (23,03,1971) (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |