1 USING: accessors arrays assocs combinators generalizations
2 grouping growable heaps kernel math math.order ranges sequences
3 sequences.private shuffle sorting splitting vectors ;
6 : find-all ( ... seq quot: ( ... elt -- ... ? ) -- ... elts )
7 [ <enumerated> ] dip '[ nip @ ] assoc-filter ; inline
9 : reduce-from ( ... seq identity quot: ( ... prev elt -- ... next ) i -- ... result )
10 [ swap ] 2dip each-from ; inline
12 : 2reduce-from ( ... seq1 seq2 identity quot: ( ... prev elt1 elt2 -- ... next ) i -- ... result )
13 [ -rot ] 2dip 2each-from ; inline
15 :: subseq* ( from to seq -- subseq )
17 from [ dup 0 < [ len + ] when ] [ 0 ] if*
18 to [ dup 0 < [ len + ] when ] [ len ] if*
19 [ 0 len clamp ] bi@ dupd max seq subseq ;
21 : safe-subseq ( from to seq -- subseq )
22 [ length '[ 0 _ clamp ] bi@ ] keep subseq ;
24 : all-subseqs ( seq -- seqs )
25 dup length [1..b] [ clump ] with map concat ;
27 : each-subseq ( ... seq quot: ( ... subseq -- ... ) -- ... )
28 [ dup length [ [0..b] ] [ ] bi ] dip '[
29 dup _ (a..b] [ rot [ subseq _ call ] keep ] with each
32 : map-like ( seq exemplar -- seq' )
33 '[ _ like ] map ; inline
35 : filter-all-subseqs-range ( ... seq range quot: ( ... subseq -- ... ? ) -- seq )
37 '[ <clumps> _ filter ] with map concat
38 ] keepdd map-like ; inline
40 : filter-all-subseqs ( ... seq quot: ( ... subseq -- ... ? ) -- seq )
41 [ dup length [1..b] ] dip filter-all-subseqs-range ; inline
43 :: longest-subseq ( seq1 seq2 -- subseq )
48 len1 1 + [ len2 1 + 0 <array> ] replicate :> table
52 y 1 - seq2 nth-unsafe = [
53 y 1 - x 1 - table nth-unsafe nth-unsafe 1 + :> len
54 len y x table nth-unsafe set-nth-unsafe
55 len n > [ len n! x end! ] when
56 ] [ 0 y x table nth-unsafe set-nth-unsafe ] if
58 ] each end n - end seq1 subseq ;
60 : pad-longest ( seq1 seq2 elt -- seq1 seq2 )
61 [ 2dup max-length ] dip [ pad-tail ] 2curry bi@ ;
63 : pad-center ( seq n elt -- padded )
64 swap pick length [-] [ drop ] [
65 [ 2/ ] [ over - ] bi rot '[ _ <repetition> ] bi@
69 : change-nths ( ... indices seq quot: ( ... elt -- ... elt' ) -- ... )
70 [ change-nth ] 2curry each ; inline
72 : push-if-index ( ..a elt i quot: ( ..a elt i -- ..b ? ) accum -- ..b )
73 [ keepd ] dip rot [ push ] [ 2drop ] if ; inline
75 : push-if* ( ..a elt quot: ( ..a elt -- ..b obj/f ) accum -- ..b )
76 [ call ] dip [ push ] [ drop ] if* ; inline
80 : (index-selector-as) ( quot length exampler -- selector accum )
81 new-resizable [ [ push-if-index ] 2curry ] keep ; inline
83 : (selector-as*) ( quot length exemplar -- selector accum )
84 new-resizable [ [ push-if* ] 2curry ] keep ; inline
88 : index-selector-as ( quot exemplar -- selector accum )
89 [ length ] keep (index-selector-as) ; inline
91 : index-selector ( quot -- selector accum )
92 V{ } index-selector-as ; inline
94 : selector-as* ( quot exemplar -- selector accum )
95 [ length ] keep (selector-as*) ; inline
97 : selector* ( quot -- selector accum ) V{ } selector-as* ; inline
99 : filter-index-as ( ... seq quot: ( ... elt i -- ... ? ) exemplar -- ... seq' )
100 pick length over [ (index-selector-as) [ each-index ] dip ] 2curry dip like ; inline
102 : filter-index ( ... seq quot: ( ... elt i -- ... ? ) -- ... seq' )
103 over filter-index-as ; inline
105 : even-indices ( seq -- seq' )
106 [ length 1 + 2/ ] keep [
107 [ [ 2 * ] dip nth-unsafe ] curry
108 ] keep map-integers-as ;
110 : odd-indices ( seq -- seq' )
112 [ [ 2 * 1 + ] dip nth-unsafe ] curry
113 ] keep map-integers-as ;
115 : compact ( ... seq quot: ( ... elt -- ... ? ) elt -- ... seq' )
116 [ split-when harvest ] dip join ; inline
118 : collapse ( ... seq quot: ( ... elt -- ... ? ) elt -- ... seq' )
120 [ [ harvest ] dip join ]
121 [ [ first empty? ] dip [ prepend ] curry when ]
122 [ [ last empty? ] dip [ append ] curry when ]
125 :: slice-when ( seq quot: ( elt -- ? ) -- seq' )
128 dup seq quot find-from drop
129 [ 2dup = [ 1 + ] when ] [ len ] if*
130 [ seq <slice> ] keep len or swap
131 ] produce nip ; inline
133 : ?<slice> ( from/f to/f sequence -- slice )
134 [ [ 0 ] unless* ] 2dip
135 over [ nip [ length ] [ ] bi ] unless
138 : sequence>slice ( sequence -- slice )
139 [ drop 0 ] [ length ] [ ] tri <slice> ; inline
141 : slice-order-by-from ( slice1 slice2 -- slice-lt slice-gt )
142 2dup [ from>> ] bi@ > [ swap ] when ; inline
144 : ordered-slices-range ( slice-lt slice-gt -- to from )
145 [ to>> ] [ from>> ] bi* ;
147 : unordered-slices-range ( slice1 slice2 -- to from )
148 slice-order-by-from ordered-slices-range ;
150 : ordered-slices-overlap? ( slice-lt slice-gt -- ? )
151 ordered-slices-range > ; inline
153 : unordered-slices-overlap? ( slice1 slice2 -- ? )
154 unordered-slices-range > ; inline
156 : slices-overlap? ( slice1 slice2 -- ? )
157 unordered-slices-overlap? ;
159 : ordered-slices-touch? ( slice-lt slice-gt -- ? )
160 ordered-slices-range >= ; inline
162 : unordered-slices-touch? ( slice1 slice2 -- ? )
163 unordered-slices-range >= ; inline
165 : slices-touch? ( slice1 slice2 -- ? )
166 unordered-slices-touch? ;
168 ERROR: slices-don't-touch slice1 slice2 ;
170 : merge-slices ( slice1 slice2 -- slice/* )
172 2dup ordered-slices-touch? [
173 [ from>> ] [ [ to>> ] [ seq>> ] bi ] bi* <slice>
178 : rotate ( seq n -- seq' )
179 over length mod dup 0 >= [ cut ] [ abs cut* ] if prepend ;
181 ERROR: underlying-mismatch slice1 slice2 ;
183 : ensure-same-underlying ( slice1 slice2 -- slice1 slice2 )
184 2dup [ seq>> ] bi@ eq? [ underlying-mismatch ] unless ;
186 : span-slices ( slice1 slice2 -- slice )
187 ensure-same-underlying
188 [ [ from>> ] bi@ min ]
190 [ drop seq>> ] 2tri <slice> ;
192 : ?span-slices ( slice1/f slice2/f -- slice )
193 2dup and [ span-slices ] [ or ] if ;
195 :: rotate! ( seq n -- )
197 n len mod dup 0 < [ len + ] when seq bounds-check drop 0 over
199 [ seq exchange-unsafe ] [ [ 1 + ] bi@ ] 2bi
200 dup len = [ drop over ] when
201 2over = [ -rot nip over ] when
204 : all-rotations ( seq -- seq' )
205 dup length <iota> [ rotate ] with map ;
209 : (appender-for) ( quot length exemplar -- appender accum )
210 new-resizable [ [ push-all ] curry compose ] keep ; inline
214 : appender-for ( quot exemplar -- appender accum )
215 [ length ] keep (appender-for) ; inline
217 : appender ( quot -- appender accum )
218 V{ } appender-for ; inline
220 : map-concat-as ( ... seq quot: ( ... elt -- ... newelt ) exemplar -- ... newseq )
221 [ appender-for [ each ] dip ] keep like ; inline
223 : >resizable ( seq -- accum ) ! fixes map-concat "cannot apply call to run-time..."
224 [ length ] keep [ new-resizable ] [ append! ] bi ;
226 : map-concat ( ... seq quot: ( ... elt -- ... newelt ) -- ... newseq )
227 over empty? [ 2drop { } ] [
228 [ [ first ] dip call ] 2keep rot [
229 >resizable [ '[ @ _ push-all ] 1 each-from ] keep
233 : map-filter-as ( ... seq map-quot: ( ... elt -- ... newelt ) filter-quot: ( ... newelt -- ... ? ) exemplar -- ... subseq )
235 [ (selector-as) [ compose each ] dip ] 2curry dip like ; inline
237 : map-filter ( ... seq map-quot: ( ... elt -- ... newelt ) filter-quot: ( ... newelt -- ... ? ) -- ... subseq )
238 pick map-filter-as ; inline
240 : map-sift ( ... seq quot: ( ... elt -- ... newelt ) -- ... newseq )
241 [ ] map-filter ; inline
243 : map-harvest ( ... seq quot: ( ... elt -- ... newelt ) -- ... newseq )
244 [ empty? not ] map-filter ; inline
246 : (each-integer-with-previous) ( ... prev i n quot: ( ... i -- ... ) -- ... )
248 [ nip call ] 4keep nipdd
249 [ 1 + ] 2dip (each-integer-with-previous)
252 ] if ; inline recursive
254 : each-integer-with-previous ( ... n quot: ( ... i -- ... ) -- ... )
255 [ f 0 ] 2dip (each-integer-with-previous) ; inline
257 : (collect-with-previous) ( quot into -- quot' )
258 [ [ keep ] dip [ set-nth-unsafe ] keepdd ] 2curry ; inline
260 : collect-with-previous ( n quot into -- )
261 (collect-with-previous) each-integer-with-previous ; inline
263 : map-integers-with ( ... len quot: ( ... prev i -- ... elt ) exemplar -- ... newseq )
264 overd [ [ collect-with-previous ] keep ] new-like ; inline
266 : map-with-previous-as ( ... seq quot: ( ... elt prev/f -- ... newelt ) exemplar -- ... newseq )
267 [ length-operator ] dip map-integers-with ; inline
269 : map-with-previous ( ... seq quot: ( ... elt prev/f -- ... newelt ) -- ... newseq )
270 over map-with-previous-as ; inline
274 : (setup-each-from) ( i seq -- n quot )
275 [ length over [-] swap ] keep '[ _ + _ nth-unsafe ] ; inline
277 : setup-each-from ( i seq quot -- n quot' )
278 [ (setup-each-from) ] dip compose ; inline
282 : map-from-as ( ... seq quot: ( ... elt -- ... newelt ) i exemplar -- ... newseq )
283 [ -rot setup-each-from ] dip map-integers-as ; inline
285 : map-from ( ... seq quot: ( ... elt -- ... newelt ) i -- ... newseq )
286 pick map-from-as ; inline
288 : map-if ( ... seq if-quot: ( ... elt -- ... ? ) map-quot: ( ... elt -- ... newelt ) -- ... newseq )
289 '[ dup @ _ when ] map ; inline
293 : push-map-if ( ..a elt filter-quot: ( ..a elt -- ..b ? ) map-quot: ( ..a elt -- ..b newelt ) accum -- ..b )
294 [ keep over ] 2dip [ when ] dip rot [ push ] [ 2drop ] if ; inline
296 : (filter-mapper-for) ( filter-quot map-quot length exempler -- filter-mapper accum )
297 new-resizable [ [ push-map-if ] 3curry ] keep ; inline
299 : filter-mapper-for ( filter-quot map-quot exemplar -- filter-mapper accum )
300 [ length ] keep (filter-mapper-for) ; inline
302 : filter-mapper ( filter-quot map-quot -- filter-mapper accum )
303 V{ } filter-mapper-for ; inline
307 : filter-map-as ( ... seq filter-quot: ( ... elt -- ... ? ) map-quot: ( ... elt -- ... newelt ) exemplar -- ... newseq )
309 [ (filter-mapper-for) [ each ] dip ] 2curry dip like ; inline
311 : filter-map ( ... seq filter-quot: ( ... elt -- ... ? ) map-quot: ( ... elt -- ... newelt ) -- ... newseq )
312 pick filter-map-as ; inline
314 : 2map-sum ( ... seq1 seq2 quot: ( ... elt1 elt2 -- ... n ) -- ... n )
315 [ 0 ] 3dip [ dip + ] curry [ rot ] prepose 2each ; inline
317 : 2count ( ... seq1 seq2 quot: ( ... elt1 elt2 -- ... ? ) -- ... n )
318 [ 1 0 ? ] compose 2map-sum ; inline
321 ( ... seq1 seq2 seq3 quot: ( ... elt1 elt2 elt3 -- ... ) i -- ... )
322 [ 3length-operator ] dip -rot each-integer-from ; inline
325 ( ..a seq1 seq2 seq3 map-quot: ( ..a elt1 elt2 elt3 -- ..b intermediate ) reduce-quot: ( ..b prev intermediate -- ..a next ) -- ..a result )
326 [ [ [ [ first ] tri@ ] 3keep ] dip [ 3dip ] keep ] dip compose 1 3each-from ; inline
328 : round-robin ( seq -- newseq )
330 [ longest length <iota> ] keep
331 [ [ ?nth ] with map ] curry map concat sift
334 : sift-as ( seq exemplar -- newseq )
337 : sift! ( seq -- newseq )
340 : harvest-as ( seq exemplar -- newseq )
341 [ empty? not ] swap filter-as ;
343 : harvest! ( seq -- newseq )
346 : head-as ( seq n exemplar -- seq' )
347 [ head-slice ] [ like ] bi* ; inline
349 : head*-as ( seq n exemplar -- seq' )
350 [ head-slice* ] [ like ] bi* ; inline
352 : tail-as ( seq n exemplar -- seq' )
353 [ tail-slice ] [ like ] bi* ; inline
355 : tail*-as ( seq n exemplar -- seq' )
356 [ tail-slice* ] [ like ] bi* ; inline
358 : trim-as ( ... seq quot: ( ... elt -- ... ? ) exemplar -- ... newseq )
359 [ trim-slice ] [ like ] bi* ; inline
361 : ?trim ( seq quot: ( elt -- ? ) -- seq/newseq )
362 over empty? [ drop ] [
363 over [ first-unsafe ] [ last-unsafe ] bi pick either?
367 : ?trim-head ( seq quot: ( elt -- ? ) -- seq/newseq )
368 over empty? [ drop ] [
369 over first-unsafe over call
370 [ trim-head ] [ drop ] if
373 : ?trim-tail ( seq quot: ( elt -- ? ) -- seq/newseq )
374 over empty? [ drop ] [
375 over last-unsafe over call
376 [ trim-tail ] [ drop ] if
379 : unsurround ( newseq seq2 seq3 -- seq1 )
380 [ ?head drop ] [ ?tail drop ] bi* ;
382 : >string-list ( seq -- seq' )
383 [ "\"" 1surround ] map "," join ;
385 : with-string-lines ( str quot -- str' )
386 [ string-lines ] dip map "\n" join ; inline
388 : prepend-lines-with-spaces ( str -- str' )
389 [ " " prepend ] with-string-lines ;
391 : one? ( ... seq quot: ( ... elt -- ... ? ) -- ... ? )
393 [ 1 + ] 2dip find-from drop not
394 ] [ 3drop f ] if ; inline
396 : map-index! ( ... seq quot: ( ... elt index -- ... newelt ) -- ... seq )
397 over [ [ sequence-index-operator ] dip collect ] keep ; inline
401 : 2sequence-index-iterator ( seq1 seq2 quot -- n quot' )
402 [ 2length-iterator [ keep ] curry ] dip compose ; inline
406 : 2each-index ( ... seq1 seq2 quot: ( ... elt1 elt2 index -- ... ) -- ... )
407 2sequence-index-iterator each-integer ; inline
409 : 2map-into ( seq1 seq2 quot into -- )
410 [ 2length-operator ] dip collect ; inline
412 : 2map! ( ... seq1 seq2 quot: ( ... elt1 elt2 -- ... newelt ) -- ... seq1 )
413 pick [ 2map-into ] keep ; inline
415 : 2map-index ( ... seq1 seq2 quot: ( ... elt1 elt2 index -- ... newelt ) -- ... newseq )
416 pick [ 2sequence-index-iterator ] dip map-integers-as ; inline
418 TUPLE: evens { seq read-only } ;
422 M: evens length seq>> length 1 + 2/ ; inline
424 M: evens virtual@ [ 2 * ] [ seq>> ] bi* ; inline
426 M: evens virtual-exemplar seq>> ; inline
428 INSTANCE: evens virtual-sequence
430 TUPLE: odds { seq read-only } ;
434 M: odds length seq>> length 2/ ; inline
436 M: odds virtual@ [ 2 * 1 + ] [ seq>> ] bi* ; inline
438 M: odds virtual-exemplar seq>> ; inline
440 INSTANCE: odds virtual-sequence
442 : until-empty ( seq quot -- )
443 [ dup empty? ] swap until drop ; inline
447 : push-index-if ( ..a elt i quot: ( ..a elt -- ..b ? ) accum -- ..b )
448 [ dip ] dip rot [ push ] [ 2drop ] if ; inline
452 : arg-where ( ... seq quot: ( ... elt -- ... ? ) -- ... indices )
453 over length <vector> [
454 [ push-index-if ] 2curry each-index
457 : arg-sort ( seq -- indices )
458 zip-index sort-keys values ;
460 : first= ( seq elt -- ? ) [ first ] dip = ; inline
461 : second= ( seq elt -- ? ) [ second ] dip = ; inline
462 : third= ( seq elt -- ? ) [ third ] dip = ; inline
463 : fourth= ( seq elt -- ? ) [ fourth ] dip = ; inline
464 : last= ( seq elt -- ? ) [ last ] dip = ; inline
465 : nth= ( n seq elt -- ? ) [ nth ] dip = ; inline
467 : first? ( ... seq quot: ( ... elt -- ... ? ) -- ... ? ) [ first ] dip call ; inline
468 : second? ( ... seq quot: ( ... elt -- ... ? ) -- ... ? ) [ second ] dip call ; inline
469 : third? ( ... seq quot: ( ... elt -- ... ? ) -- ... ? ) [ third ] dip call ; inline
470 : fourth? ( ... seq quot: ( ... elt -- ... ? ) -- ... ? ) [ fourth ] dip call ; inline
471 : last? ( ... seq quot: ( ... elt -- ... ? ) -- ... ? ) [ last ] dip call ; inline
472 : nth? ( ... n seq quot: ( ... elt -- ... ? ) -- ... ? ) [ nth ] dip call ; inline
474 : loop>sequence** ( ... quot: ( ... -- ... obj ? ) exemplar -- ... seq )
475 [ ] swap produce-as nip ; inline
477 : loop>array** ( ... quot: ( ... -- ... obj ? ) -- ... array )
478 { } loop>sequence** ; inline
480 : loop>sequence* ( ... quot: ( ... -- ... obj ? ) exemplar -- ... seq )
481 [ t ] [ '[ [ _ dip ] [ f f f ] if* ] [ swap ] ] [ produce-as 2nip ] tri* ; inline
483 : loop>array* ( ... quot: ( ... -- ... obj ? ) -- ... array )
484 { } loop>sequence* ; inline
486 : loop>sequence ( ... quot: ( ... -- ... obj/f ) exemplar -- ... seq )
487 [ [ dup ] compose [ ] ] dip produce-as nip ; inline
489 : loop>array ( ... quot: ( ... -- ... obj/f ) -- ... array )
490 { } loop>sequence ; inline
492 : zero-loop>sequence ( ... quot: ( ... n -- ... obj/f ) exemplar -- ... seq )
493 [ 0 ] [ '[ _ keep 1 + swap ] ] [ loop>sequence ] tri* nip ; inline
495 : zero-loop>array ( quot: ( ..a n -- ..a obj ) -- seq )
496 { } zero-loop>sequence ; inline
498 : iterate-heap-while ( heap quot1: ( value key -- slurp? ) quot2: ( value key -- obj/f ) -- obj/f loop? )
502 [ [ heap-peek ] 2dip drop 2keep ]
504 nip ! ( pop? value key heap quot2 )
506 swap heap-pop* call( value key -- obj/f ) t
513 : slurp-heap-while-map ( heap quot1: ( value key -- slurp? ) quot2: ( value key -- obj/f ) -- seq )
514 '[ _ _ _ iterate-heap-while ] loop>array* ; inline
516 : heap>pairs ( heap -- pairs )
517 [ 2drop t ] [ swap 2array ] slurp-heap-while-map ;
519 : map-zip-swap ( quot: ( x -- y ) -- alist )
520 '[ _ keep ] map>alist ; inline
522 : ?heap-pop-value>array ( heap -- array )
523 dup heap-empty? [ drop { } ] [ heap-pop drop 1array ] if ;
527 : (reverse) ( seq -- newseq )
528 dup [ length ] keep new-sequence
529 [ 0 swap copy-unsafe ] keep reverse! ;
533 : reverse-as ( seq exemplar -- newseq )
534 [ (reverse) ] [ like ] bi* ;
536 : map-product ( ... seq quot: ( ... elt -- ... n ) -- ... n )
537 [ 1 ] 2dip [ dip * ] with-assoc each ; inline
539 : insert-nth! ( elt n seq -- )
540 [ length ] keep ensure swap pick (a..b]
541 over '[ [ 1 + ] keep _ move-unsafe ] each
544 : set-nths ( value indices seq -- )
545 swapd '[ _ swap _ set-nth ] each ; inline
547 : set-nths-unsafe ( value indices seq -- )
548 swapd '[ _ swap _ set-nth-unsafe ] each ; inline
552 : (map-find-index) ( seq quot find-quot -- result i elt )
553 [ [ f ] 2dip [ [ nip ] 2dip call dup ] curry ] dip call
554 [ [ [ drop f ] unless ] keep ] dip ; inline
558 : map-find-index ( ... seq quot: ( ... elt index -- ... result/f ) -- ... result i elt )
559 [ find-index ] (map-find-index) ; inline
561 : filter-length ( seq n -- seq' ) '[ length _ = ] filter ;
563 : all-shortest ( seqs -- seqs' ) dup shortest length filter-length ;
565 : all-longest ( seqs -- seqs' ) dup longest length filter-length ;
567 : remove-first ( obj seq -- seq' )
568 [ index ] keep over [ remove-nth ] [ nip ] if ;
570 : remove-first! ( obj seq -- seq )
571 [ index ] keep over [ remove-nth! ] [ nip ] if ;
573 : remove-last ( obj seq -- seq' )
574 [ last-index ] keep over [ remove-nth ] [ nip ] if ;
576 : remove-last! ( obj seq -- seq )
577 [ last-index ] keep over [ remove-nth! ] [ nip ] if ;
579 : ?first2 ( seq -- first/f second/f )
582 { 1 [ first-unsafe f ] }
583 [ drop first2-unsafe ]
586 : ?first3 ( seq -- first/f second/f third/f )
589 { 1 [ first-unsafe f f ] }
590 { 2 [ first2-unsafe f ] }
591 [ drop first3-unsafe ]
594 : ?first4 ( seq -- first/f second/f third/f fourth/f )
596 { 0 [ drop f f f f ] }
597 { 1 [ first-unsafe f f f ] }
598 { 2 [ first2-unsafe f f ] }
599 { 3 [ first3-unsafe f ] }
600 [ drop first4-unsafe ]
603 : cut-when ( ... seq quot: ( ... elt -- ... ? ) -- ... before after )
604 [ find drop ] keepd swap
605 [ cut ] [ f over like ] if* ; inline
607 : nth* ( n seq -- elt )
608 [ length 1 - swap - ] [ nth ] bi ; inline
610 : each-index-from ( ... seq quot: ( ... elt index -- ... ) i -- ... )
611 -rot sequence-index-operator each-integer-from ; inline
615 : select-by* ( ... seq quot: ( ... elt -- ... x ) compare: ( obj1 obj2 -- ? ) -- ... i elt )
617 [ keep swap ] curry [ dip ] curry
618 [ [ first 0 ] dip call ] 2keep
619 [ 2curry 3dip 5 npick pick ] curry
621 [ [ 3drop ] [ [ 3drop ] 3dip ] if ] compose
622 ] bi* compose 1 each-index-from nip swap ; inline
626 : supremum-by* ( ... seq quot: ( ... elt -- ... x ) -- ... i elt )
627 [ after? ] select-by* ; inline
629 : infimum-by* ( ... seq quot: ( ... elt -- ... x ) -- ... i elt )
630 [ before? ] select-by* ; inline
632 : arg-max ( seq -- n )
633 [ ] supremum-by* drop ;
635 : arg-min ( seq -- n )
636 [ ] infimum-by* drop ;
638 : ?supremum ( seq/f -- elt/f )
640 [ ] [ 2dup and [ max ] [ dupd ? ] if ] map-reduce
643 : ?infimum ( seq/f -- elt/f )
645 [ ] [ 2dup and [ min ] [ dupd ? ] if ] map-reduce
648 : map-infimum ( seq quot: ( ... elt -- ... elt' ) -- elt' )
649 [ min ] map-reduce ; inline
651 : map-supremum ( seq quot: ( ... elt -- ... elt' ) -- elt' )
652 [ max ] map-reduce ; inline
654 : change-last ( seq quot -- )
655 [ index-of-last ] [ change-nth ] bi* ; inline
657 : change-last-unsafe ( seq quot -- )
658 [ index-of-last ] [ change-nth-unsafe ] bi* ; inline
660 : replicate-into ( ... seq quot: ( ... -- ... newelt ) -- ... )
661 over [ length ] 2dip '[ _ dip _ set-nth-unsafe ] each-integer ; inline
663 : count* ( ... seq quot: ( ... elt -- ... ? ) -- ... % )
664 over [ count ] [ length ] bi* / ; inline
666 : sequence-index-operator-last ( n seq quot -- n quot' )
667 [ [ nth-unsafe ] curry [ keep ] curry ] dip compose ; inline
669 : find-last-index-from ( ... n seq quot: ( ... elt i -- ... ? ) -- ... i elt )
671 _ [ sequence-index-operator-last find-last-integer ] keepd
673 ] bounds-check-call ; inline
675 : find-last-index ( ... seq quot: ( ... elt i -- ... ? ) -- ... i elt )
676 [ index-of-last ] dip find-last-index-from ; inline
678 : map-find-last-index ( ... seq quot: ( ... elt index -- ... result/f ) -- ... result i elt )
679 [ find-last-index ] (map-find-index) ; inline
681 :: (start-all) ( seq subseq increment -- indices )
683 [ seq subseq subseq-index-from dup ]
684 [ [ increment + ] keep ] produce nip ;
686 : start-all ( seq subseq -- indices )
687 dup length (start-all) ; inline
689 : start-all* ( seq subseq -- indices )
690 1 (start-all) ; inline
692 : count-subseq ( seq subseq -- n )
693 start-all length ; inline
695 : count-subseq* ( seq subseq -- n )
696 start-all* length ; inline
698 : assoc-zip-with ( quot: ( key value -- calc ) -- alist )
699 '[ _ 2keep 2array swap ] assoc-map ; inline
701 : take-while ( ... seq quot: ( ... elt -- ... ? ) -- head-slice )
702 [ '[ @ not ] find drop ] keepd swap
703 [ dup length ] unless* head-slice ; inline
705 : drop-while ( ... seq quot: ( ... elt -- ... ? ) -- tail-slice )
706 [ '[ @ not ] find drop ] keepd swap
707 [ dup length ] unless* tail-slice ; inline
709 : count-head ( seq quot -- n )
710 [ not ] compose [ find drop ] keepd length or ; inline
712 : count-tail ( seq quot -- n )
713 [ not ] compose [ find-last drop ] keepd
714 length swap [ - 1 - ] when* ; inline
716 :: shorten* ( vector n -- seq )
720 :: interleaved-as ( seq glue exemplar -- newseq )
721 seq length dup 1 - + 0 max exemplar new-sequence :> newseq
722 seq [ 2 * newseq set-nth-unsafe ] each-index
723 seq length 1 - [ 2 * 1 + glue swap newseq set-nth-unsafe ] each-integer
726 : interleaved ( seq glue -- newseq )
727 over interleaved-as ;
729 : extract! ( ... seq quot: ( ... elt -- ... ? ) -- ... seq )
730 [ dup ] compose over [ length ] keep new-resizable
731 [ [ push-when ] 2curry reject! ] keep swap like ; inline
733 : find-pred-loop ( ... i n seq quot: ( ... elt -- ... calc ? ) -- ... calc/f i/f elt/f )
737 [ [ 3drop ] 2dip rot ]
738 [ 2drop [ 1 + ] 3dip find-pred-loop ] if
741 ] if ; inline recursive
743 : find-pred ( ... seq quot: ( ... elt -- ... calc ) pred: ( ... calc -- ... ? ) -- ... calc/f i/f elt/f )
745 [ [ length check-length ] keep ] 2dip
746 '[ nth-unsafe _ keep swap _ keep swap ] find-pred-loop swapd ; inline
748 ! https://en.wikipedia.org/wiki/Maximum_subarray_problem
749 ! Kadane's algorithm O(n) largest sum in subarray
750 : max-subarray-sum ( seq -- sum )
752 [ [ + ] keep max [ max ] keep ] each drop ;
755 { from integer read-only initial: 0 }
756 { to integer read-only initial: 0 }
758 { step integer read-only } ;
760 :: <step-slice> ( from/f to/f step seq -- step-slice )
761 step zero? [ "can't be zero" throw ] when
767 from/f [ len ] unless*
770 [ dup 0 < [ len + ] when 0 len clamp ] bi@
771 ! FIXME: make this work with steps
772 seq dup slice? [ collapse-slice ] when
773 step step-slice boa ;
775 M: step-slice virtual-exemplar seq>> ; inline
777 M: step-slice virtual@
778 [ step>> * ] [ from>> + ] [ seq>> ] tri ; inline
781 [ to>> ] [ from>> - ] [ step>> ] tri
782 dup 0 < [ [ neg 0 max ] dip neg ] when /mod
783 zero? [ 1 + ] unless ; inline
785 INSTANCE: step-slice virtual-sequence
787 : 2nested-each ( seq1 seq2 quot -- )
792 : 3nested-each ( seq1 seq2 seq3 quot -- )
795 swap _ with with each
797 ] with with each ; inline
799 : 2nested-map ( seq1 seq2 quot -- seq )
800 2over [ length ] bi@ * reach
803 [ [ push ] curry compose 2nested-each ] keep
806 : 3nested-map ( seq1 seq2 seq3 quot -- seq )
807 3 nover [ length ] tri@ * * 5 npick
810 [ [ push ] curry compose 3nested-each ] keep
813 : prev ( n seq -- obj ) [ 1 - ] dip nth ; inline
814 : ?prev ( n seq -- obj/f ) [ 1 - ] dip ?nth ; inline
815 : ??prev ( n seq -- obj/f ? ) [ 1 - ] dip ??nth ; inline
816 : prev-of ( seq n -- obj ) 1 - nth-of ; inline
817 : ?prev-of ( seq n -- obj/f ) 1 - ?nth-of ; inline
818 : ??prev-of ( seq n -- obj/f ) 1 - ??nth-of ; inline
820 : prev-identity ( i seq -- identity i seq )
821 2dup ??prev [ drop 0 ] unless -rot ; inline
823 : each-prior-identity-from ( ... identity i seq quot: ( ... prior elt -- ... ) -- ... )
825 length-operator each-integer-from drop ; inline
827 : each-prior-from ( ... i seq quot: ( ... prior elt -- ... ) -- ... )
828 [ prev-identity ] dip each-prior-identity-from ; inline
830 : each-prior ( ... seq quot: ( ... prior elt -- ... ) -- ... )
831 0 -rot each-prior-from ; inline
833 : map-prior-identity-from-as ( ... identity i seq quot: ( ... prior elt -- elt' ) exemplar -- seq' )
835 '[ [ swap @ ] keep swap ] length-operator
836 ] dip map-integers-from-as nip ; inline
838 : map-prior-identity-as ( ... identity seq quot: ( ... prior elt -- elt' ) exemplar -- seq' )
839 [ 0 ] 3dip map-prior-identity-from-as ; inline
841 : map-prior-from-as ( ... i seq quot: ( ... prior elt -- elt' ) exemplar -- seq' )
842 [ prev-identity ] 2dip map-prior-identity-from-as ; inline
844 : map-prior-as ( ... seq quot: ( ... prior elt -- elt' ) exemplar -- seq' )
845 0 -roll map-prior-from-as ; inline
847 : map-prior-from ( ... i seq quot: ( ... prior elt -- elt' ) -- seq' )
848 over map-prior-from-as ; inline
850 : map-prior ( ... seq quot: ( ... prior elt -- elt' ) -- seq' )
851 over map-prior-as ; inline
853 TUPLE: virtual-zip-index seq ;
855 C: <zip-index> virtual-zip-index
857 M: virtual-zip-index length seq>> length ; inline
859 M: virtual-zip-index nth-unsafe
860 over [ seq>> nth-unsafe ] [ 2array ] bi* ; inline
862 INSTANCE: virtual-zip-index immutable-sequence
864 : nth-index ( n obj seq -- i )
865 [ = dup [ drop 1 - dup 0 < ] when ] with find drop nip ;