:: subseq* ( from to seq -- subseq )
seq length :> len
from [ dup 0 < [ len + ] when ] [ 0 ] if*
- to [ dup 0 < [ len + ] when ] [ len ] if* [ 0 len clamp ] bi@ dupd max seq subseq ;
+ to [ dup 0 < [ len + ] when ] [ len ] if*
+ [ 0 len clamp ] bi@ dupd max seq subseq ;
: safe-subseq ( from to seq -- subseq )
[ length '[ 0 _ clamp ] bi@ ] keep subseq ;
: all-subseqs ( seq -- seqs )
dup length [1..b] [ clump ] with map concat ;
-:: each-subseq ( ... seq quot: ( ... subseq -- ... ) -- ... )
- seq length :> len
- len [0..b] [| from |
- from len (a..b] [| to |
- from to seq subseq quot call
- ] each
- ] each ; inline
+: each-subseq ( ... seq quot: ( ... subseq -- ... ) -- ... )
+ [ dup length [ [0..b] ] [ ] bi ] dip '[
+ dup _ (a..b] [ rot [ subseq _ call ] keep ] with each
+ ] each drop ; inline
: map-like ( seq exemplar -- seq' )
'[ _ like ] map ; inline
: even-indices ( seq -- seq' )
[ length 1 + 2/ ] keep [
[ [ 2 * ] dip nth-unsafe ] curry
- ] keep map-integers ;
+ ] keep map-integers-as ;
: odd-indices ( seq -- seq' )
[ length 2/ ] keep [
[ [ 2 * 1 + ] dip nth-unsafe ] curry
- ] keep map-integers ;
+ ] keep map-integers-as ;
: compact ( ... seq quot: ( ... elt -- ... ? ) elt -- ... seq' )
[ split-when harvest ] dip join ; inline
overd [ [ collect-with-previous ] keep ] new-like ; inline
: map-with-previous-as ( ... seq quot: ( ... elt prev/f -- ... newelt ) exemplar -- ... newseq )
- [ (1each) ] dip map-integers-with ; inline
+ [ length-operator ] dip map-integers-with ; inline
: map-with-previous ( ... seq quot: ( ... elt prev/f -- ... newelt ) -- ... newseq )
over map-with-previous-as ; inline
PRIVATE>
: map-from-as ( ... seq quot: ( ... elt -- ... newelt ) i exemplar -- ... newseq )
- [ -rot setup-each-from ] dip map-integers ; inline
+ [ -rot setup-each-from ] dip map-integers-as ; inline
: map-from ( ... seq quot: ( ... elt -- ... newelt ) i -- ... newseq )
pick map-from-as ; inline
: 3each-from
( ... seq1 seq2 seq3 quot: ( ... elt1 elt2 elt3 -- ... ) i -- ... )
- [ (3each) ] dip -rot (each-integer) ; inline
+ [ (3each) ] dip -rot each-integer-from ; inline
: 3map-reduce
( ..a seq1 seq2 seq3 map-quot: ( ..a elt1 elt2 elt3 -- ..b intermediate ) reduce-quot: ( ..b prev intermediate -- ..a next ) -- ..a result )
] [ 3drop f ] if ; inline
: map-index! ( ... seq quot: ( ... elt index -- ... newelt ) -- ... seq )
- over [ [ (each-index) ] dip collect ] keep ; inline
+ over [ [ sequence-index-operator ] dip collect ] keep ; inline
<PRIVATE
pick [ 2map-into ] keep ; inline
: 2map-index ( ... seq1 seq2 quot: ( ... elt1 elt2 index -- ... newelt ) -- ... newseq )
- pick [ (2each-index) ] dip map-integers ; inline
+ pick [ (2each-index) ] dip map-integers-as ; inline
TUPLE: evens { seq read-only } ;
: until-empty ( seq quot -- )
[ dup empty? ] swap until drop ; inline
-: arg-max ( seq -- n )
- [ supremum ] keep index ;
-
-: arg-min ( seq -- n )
- [ infimum ] keep index ;
-
<PRIVATE
: push-index-if ( ..a elt i quot: ( ..a elt -- ..b ? ) accum -- ..b )
[ length 1 - swap - ] [ nth ] bi ; inline
: each-index-from ( ... seq quot: ( ... elt index -- ... ) i -- ... )
- -rot (each-index) (each-integer) ; inline
+ -rot sequence-index-operator each-integer-from ; inline
<PRIVATE
: infimum-by* ( ... seq quot: ( ... elt -- ... x ) -- ... i elt )
[ before? ] select-by* ; inline
+: arg-max ( seq -- n )
+ [ ] supremum-by* drop ;
+
+: arg-min ( seq -- n )
+ [ ] infimum-by* drop ;
+
: ?supremum ( seq/f -- elt/f )
[ f ] [
[ ] [ 2dup and [ max ] [ dupd ? ] if ] map-reduce
: count* ( ... seq quot: ( ... elt -- ... ? ) -- ... % )
over [ count ] [ length ] bi* / ; inline
+: sequence-index-operator-last ( n seq quot -- n quot' )
+ [ [ nth-unsafe ] curry [ keep ] curry ] dip compose ; inline
+
+: find-last-index-from ( ... n seq quot: ( ... elt i -- ... ? ) -- ... i elt )
+ '[
+ _ [ sequence-index-operator-last find-last-integer ] keepd
+ index/element
+ ] bounds-check-find ; inline
+
: find-last-index ( ... seq quot: ( ... elt i -- ... ? ) -- ... i elt )
- [ [ 1 - ] dip find-last-integer ] (find-index) ; inline
+ [ [ length 1 - ] keep ] dip find-last-index-from ; inline
: map-find-last-index ( ... seq quot: ( ... elt index -- ... result/f ) -- ... result i elt )
[ find-last-index ] (map-find-index) ; inline
:: (start-all) ( seq subseq increment -- indices )
0
- [ [ subseq seq ] dip subseq-start-from dup ]
+ [ seq subseq subsequence-starts-from dup ]
[ [ increment + ] keep ] produce nip ;
: start-all ( seq subseq -- indices )
: find-pred-loop ( ... i n seq quot: ( ... elt -- ... calc ? ) -- ... calc/f i/f elt/f )
2pick < [
[ nipd call ] 4keep
- 7 nrot 7 nrot 7 nrot
+ 3 7 0 nrotated
[ [ 3drop ] 2dip rot ]
[ 2drop [ 1 + ] 3dip find-pred-loop ] if
] [