Fix errors

core/debugger/debugger.factor

@@ -6,7 +6,7 @@ strings io.styles vectors words system splitting math.parser
 tuples continuations continuations.private combinators
 generic.math io.streams.duplex classes compiler.units
 generic.standard vocabs threads threads.private init
-kernel.private libc ;
+kernel.private libc io.encodings ;
 IN: debugger
 
 GENERIC: error. ( error -- )
@@ -282,6 +282,10 @@ M: thread error-in-thread ( error thread -- )
         ] bind
     ] if ;
 
+M: encode-error summary drop "Character encoding error" ;
+
+M: decode-error summary drop "Character decoding error" ;
+
 <PRIVATE
 
 : init-debugger ( -- )

extra/io/encodings/utf16/utf16.factor

@@ -18,13 +18,13 @@ TUPLE: utf16 ;
     over [ 8 shift bitor ] [ 2drop replacement-char ] if ;
 
 : double-be ( stream byte -- stream char )
-    over stream-read1 prepend-nums ;
+    over stream-read1 swap append-nums ;
 
 : quad-be ( stream byte -- stream char )
     double-be over stream-read1 [
         dup -2 shift BIN: 110111 number= [
             >r 2 shift r> BIN: 11 bitand bitor
-            over stream-read1 prepend-nums HEX: 10000 +
+            over stream-read1 swap append-nums HEX: 10000 +
         ] [ 2drop dup stream-read1 drop replacement-char ] if
     ] when* ;