src/Pure/ROOT.scala

--- a/src/Pure/ROOT.scala	Tue Mar 22 16:49:18 2022 +0100
+++ b/src/Pure/ROOT.scala	Tue Mar 22 18:12:58 2022 +0100
@@ -18,6 +18,7 @@
   val quote = Library.quote _
   val commas = Library.commas _
   val commas_quote = Library.commas_quote _
+  val proper_bool = Library.proper_bool _
   val proper_string = Library.proper_string _
   def proper_list[A](list: List[A]): Option[List[A]] = Library.proper_list(list)
 }