: classify ( seq -- seq' ) classify* 2nip ; inline
: occurrence-count-by ( seq quot: ( elt -- elt' ) -- hash seq' )
- '[ nip @ over inc-at* drop ] [ H{ } clone ] 2dip 0accumulate ; inline
+ '[ nip @ over inc-at* drop ] [ H{ } clone ] 2dip { } 0accumulate-as ; inline
: progressive-index-by-as ( seq1 seq2 quot exemplar -- hash seq' )
[