--- a/Integer.st	Thu Sep 01 20:53:39 2016 +0200
+++ b/Integer.st	Thu Sep 01 21:03:29 2016 +0200
@@ -286,10 +286,18 @@
             "-xxr<number> is invalid; should be xxr-<val>"
 
             negative ifTrue:[
-                'Integer [warning]: invalid (negative) radix ignored' errorPrintCR.
-                negative := false
+                'Integer [warning]: invalid (negative) radix; please use xxr-<val> instead of -xxr<number>' errorPrintCR.
+                "/ negative := false
             ].
             str next.
+            nextChar := str peekOrNil.
+            nextChar == $- ifTrue:[
+                negative ifTrue:[
+                    'Integer [warning]: invalid double sign; please use xxr-<val> instead of -xxr<number>' errorPrintCR.
+                ].
+                negative := true.
+                str next.
+            ].
             value := self readFrom:str radix:value
         ].
         negative ifTrue:[