] until 3drop ;
: all-rotations ( seq -- seq' )
- dup length iota [ rotate ] with map ;
+ dup length <iota> [ rotate ] with map ;
<PRIVATE
: round-robin ( seq -- newseq )
[ { } ] [
- [ longest length iota ] keep
+ [ longest length <iota> ] keep
[ [ ?nth ] with map ] curry map concat sift
] if-empty ;