src/Pure/Tools/doc.scala

 
 Access to Isabelle documentation.
 */
 
 package isabelle
-
-
-import scala.util.matching.Regex
 
 
 object Doc
 {
   /* dirs */

       val b = Library.try_unprefix("$ISABELLE_HOME/", a).getOrElse(a)
       Some(Text_File(b, path))
     }
     else None
 
-  private val Section_Entry = new Regex("""^(\S.*)\s*$""")
-  private val Doc_Entry = new Regex("""^\s+(\S+)\s+(.+)\s*$""")
+  private val Section_Entry = """^(\S.*)\s*$""".r
+  private val Doc_Entry = """^\s+(\S+)\s+(.+)\s*$""".r
 
   private def release_notes(): List[Entry] =
     Section("Release Notes", true) ::
       Path.split(Isabelle_System.getenv_strict("ISABELLE_DOCS_RELEASE_NOTES")).flatMap(text_file)