diff -r a037f01aedab -r 029de1598940 src/Pure/General/date.scala
--- a/src/Pure/General/date.scala	Fri May 07 16:49:08 2021 +0200
+++ b/src/Pure/General/date.scala	Fri May 07 21:03:20 2021 +0200
@@ -38,6 +38,7 @@
     val default: Format = Format("dd-MMM-uuuu HH:mm:ss xx")
     val date: Format = Format("dd-MMM-uuuu")
     val time: Format = Format("HH:mm:ss")
+    val alt_date: Format = Format("uuuuMMdd")
   }
 
   abstract class Format private