--- a/SequenceableCollection.st	Fri Mar 02 18:20:32 2018 +0100
+++ b/SequenceableCollection.st	Fri Mar 02 18:48:41 2018 +0100
@@ -1,3 +1,5 @@
+"{ Encoding: utf8 }"
+
 "
  COPYRIGHT (c) 1989 by Claus Gittinger
 	      All Rights Reserved
@@ -683,6 +685,12 @@
     "
 !
 
+destroy
+    "used with cryptographic keys, to wipe their contents after use"
+
+    self clearContents
+!
+
 joinWith:separatingElement
     "return a collection generated by concatenating my elements
      and embedding separatingElement in between.
@@ -761,7 +769,6 @@
     ^ self replaceFrom:start to:stop with:anArray startingAt:repStart
 ! !
 
-
 !SequenceableCollection methodsFor:'accessing'!
 
 after:anObject
@@ -5447,6 +5454,12 @@
     "Modified: / 20.5.1998 / 15:14:11 / cg"
 !
 
+clearContents
+    "to be used with cryptographic keys, to wipe their contents after use"
+
+    self atAllPut:0
+!
+
 from:index1 to:index2 put:anObject
     "replace the elements from index1 to index2 of the collection
      by the argument, anObject.