     [ -rot 2nth-unsafe <=> ] [ [ length ] compare ] if* ;
 
 : sequence= ( seq1 seq2 -- ? )
-    2dup [ length ] bi@ number=
+    2dup [ length ] bi@ =
     [ mismatch not ] [ 2drop f ] if ; inline
 
 : sequence-hashcode-step ( oldhash newpart -- newhash )


M: sequence shorten 2dup length < [ set-length ] [ 2drop ] if ;

: empty? ( seq -- ? ) length zero? ; inline

: if-empty ( seq quot1 quot2 -- )
    [ dup empty? ] [ [ drop ] prepose ] [ ] tri* if ; inline

    prepose curry ; inline

: (interleave) ( n elt between quot -- )
    roll 0 = [ nip ] [ swapd 2slip ] if call ; inline

PRIVATE>

