regex - Scala 中占位符替换正则表达式的语法是什么？

Question

所以我可以写:

val res = """(\d*).*""".r.replaceAllIn(s,"""\1""")

到目前为止，我得到的是文字“1”而不是捕获的组。

提前谢谢你。

Answer 1

试试这个:$1 而不是 \1。

Scala 的 Regex 在底层使用 java.util.regex(至少在 JVM 上)。现在，如果您在 Java 文档中查找 replaceAll，您将看到:

Note that backslashes () and dollar signs ($) in the replacement string may cause the results to be different than if it were being treated as a literal replacement string. Dollar signs may be treated as references to captured subsequences as described above, and backslashes are used to escape literal characters in the replacement string.