unused -- clone of Option.apply;

--- a/src/Pure/ROOT.scala	Wed Jan 15 15:05:33 2020 +0100
+++ b/src/Pure/ROOT.scala	Wed Jan 15 16:18:24 2020 +0100
@@ -18,7 +18,6 @@
   val quote = Library.quote _
   val commas = Library.commas _
   val commas_quote = Library.commas_quote _
-  def proper[A](x: A): Option[A] = Library.proper(x)
   val proper_string = Library.proper_string _
   def proper_list[A](list: List[A]): Option[List[A]] = Library.proper_list(list)
 }

--- a/src/Pure/library.scala	Wed Jan 15 15:05:33 2020 +0100
+++ b/src/Pure/library.scala	Wed Jan 15 16:18:24 2020 +0100
@@ -268,9 +268,6 @@
 
   /* proper values */
 
-  def proper[A](x: A): Option[A] =
-    if (x == null) None else Some(x)
-
   def proper_string(s: String): Option[String] =
     if (s == null || s == "") None else Some(s)