The combinators in the sequences.deep vocabulary are variants of standard sequence combinators which traverse nested subsequences.

deep-each ( obj quot: ( elt -- ) -- )

deep-map ( obj quot: ( elt -- elt' ) -- newobj )

deep-filter ( obj quot: ( elt -- ? ) -- seq )

deep-find ( obj quot -- elt )

deep-any? ( obj quot -- ? )

deep-map! ( obj quot: ( elt -- elt' ) -- obj )

A utility word to collapse nested subsequences:

flatten ( obj -- seq )