--- a/ExternalBytes.st	Tue Jun 20 17:31:22 2006 +0200
+++ b/ExternalBytes.st	Tue Jun 20 17:33:08 2006 +0200
@@ -1175,6 +1175,14 @@
     ^ size
 !
 
+isValid
+    "true if I gave an address"
+
+%{  /* NOCONTEXT */
+    RETURN ((__INST(address_) == nil) ? false : true );
+%}
+!
+
 species
     "when copying, or concatenating, return instances of this class"
 
@@ -1255,7 +1263,7 @@
 !ExternalBytes class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic/ExternalBytes.st,v 1.62 2006-06-20 15:31:22 ca Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic/ExternalBytes.st,v 1.63 2006-06-20 15:33:08 ca Exp $'
 ! !
 
 ExternalBytes initialize!