! Copyright (C) 2004, 2008 Chris Double, Matthew Willis, James Cash.
! See http://factorcode.org/license.txt for BSD license.
-USING: kernel sequences math vectors arrays namespaces make
-quotations promises combinators io lists accessors ;
+USING: accessors arrays combinators io kernel lists math
+promises quotations sequences ;
IN: lists.lazy
-M: promise car ( promise -- car )
- force car ;
+M: promise car force car ;
-M: promise cdr ( promise -- cdr )
- force cdr ;
+M: promise cdr force cdr ;
-M: promise nil? ( cons -- bool )
- force nil? ;
-
-! Both 'car' and 'cdr' are promises
-TUPLE: lazy-cons car cdr ;
+M: promise nil? force nil? ;
+
+TUPLE: lazy-cons-state { car promise } { cdr promise } ;
+
+C: <lazy-cons-state> lazy-cons-state
: lazy-cons ( car cdr -- promise )
- [ promise ] bi@ \ lazy-cons boa
- T{ promise f f t f } clone
- swap >>value ;
+ [ <promise> ] bi@ <lazy-cons-state>
+ [ f t ] dip promise boa ;
-M: lazy-cons car ( lazy-cons -- car )
- car>> force ;
+M: lazy-cons-state car car>> force ;
-M: lazy-cons cdr ( lazy-cons -- cdr )
- cdr>> force ;
+M: lazy-cons-state cdr cdr>> force ;
-M: lazy-cons nil? ( lazy-cons -- bool )
- nil eq? ;
+M: lazy-cons-state nil? car nil? ;
: 1lazy-list ( a -- lazy-cons )
[ nil ] lazy-cons ;
TUPLE: memoized-cons original car cdr nil? ;
-: not-memoized ( -- obj )
- { } ;
-
-: not-memoized? ( obj -- bool )
- not-memoized eq? ;
+SYMBOL: +not-memoized+
: <memoized-cons> ( cons -- memoized-cons )
- not-memoized not-memoized not-memoized
+ +not-memoized+ +not-memoized+ +not-memoized+
memoized-cons boa ;
-M: memoized-cons car ( memoized-cons -- car )
- dup car>> not-memoized? [
+M: memoized-cons car
+ dup car>> +not-memoized+ eq? [
dup original>> car [ >>car drop ] keep
] [
car>>
] if ;
-M: memoized-cons cdr ( memoized-cons -- cdr )
- dup cdr>> not-memoized? [
+M: memoized-cons cdr
+ dup cdr>> +not-memoized+ eq? [
dup original>> cdr [ >>cdr drop ] keep
] [
cdr>>
] if ;
-M: memoized-cons nil? ( memoized-cons -- bool )
- dup nil?>> not-memoized? [
- dup original>> nil? [ >>nil? drop ] keep
+M: memoized-cons nil?
+ dup nil?>> +not-memoized+ eq? [
+ dup original>> nil? [ >>nil? drop ] keep
] [
nil?>>
] if ;
C: <lazy-map> lazy-map
-: lazy-map ( list quot -- result )
+: lmap-lazy ( list quot -- result )
over nil? [ 2drop nil ] [ <lazy-map> <memoized-cons> ] if ;
-M: lazy-map car ( lazy-map -- car )
- [ cons>> car ] keep
- quot>> call( old -- new ) ;
+M: lazy-map car
+ [ cons>> car ] [ quot>> call( old -- new ) ] bi ;
-M: lazy-map cdr ( lazy-map -- cdr )
- [ cons>> cdr ] keep
- quot>> lazy-map ;
+M: lazy-map cdr
+ [ cons>> cdr ] [ quot>> lmap-lazy ] bi ;
-M: lazy-map nil? ( lazy-map -- bool )
+M: lazy-map nil?
cons>> nil? ;
TUPLE: lazy-take n cons ;
C: <lazy-take> lazy-take
: ltake ( n list -- result )
- over zero? [ 2drop nil ] [ <lazy-take> ] if ;
+ over zero? [ 2drop nil ] [ <lazy-take> ] if ;
-M: lazy-take car ( lazy-take -- car )
+M: lazy-take car
cons>> car ;
-M: lazy-take cdr ( lazy-take -- cdr )
- [ n>> 1- ] keep
- cons>> cdr ltake ;
+M: lazy-take cdr
+ [ n>> 1 - ] [ cons>> cdr ltake ] bi ;
-M: lazy-take nil? ( lazy-take -- bool )
- dup n>> zero? [
- drop t
- ] [
- cons>> nil?
- ] if ;
+M: lazy-take nil?
+ dup n>> zero? [ drop t ] [ cons>> nil? ] if ;
TUPLE: lazy-until cons quot ;
C: <lazy-until> lazy-until
-: luntil ( list quot -- result )
+: luntil ( list quot: ( elt -- ? ) -- result )
over nil? [ drop ] [ <lazy-until> ] if ;
-M: lazy-until car ( lazy-until -- car )
- cons>> car ;
+M: lazy-until car
+ cons>> car ;
-M: lazy-until cdr ( lazy-until -- cdr )
- [ cons>> unswons ] keep quot>> tuck call( elt -- ? )
- [ 2drop nil ] [ luntil ] if ;
+M: lazy-until cdr
+ [ [ cons>> cdr ] [ quot>> ] bi ]
+ [ [ cons>> car ] [ quot>> ] bi call( elt -- ? ) ] bi
+ [ 2drop nil ] [ luntil ] if ;
-M: lazy-until nil? ( lazy-until -- bool )
- drop f ;
+M: lazy-until nil?
+ drop f ;
TUPLE: lazy-while cons quot ;
C: <lazy-while> lazy-while
-: lwhile ( list quot -- result )
+: lwhile ( list quot: ( elt -- ? ) -- result )
over nil? [ drop ] [ <lazy-while> ] if ;
-M: lazy-while car ( lazy-while -- car )
- cons>> car ;
+M: lazy-while car
+ cons>> car ;
-M: lazy-while cdr ( lazy-while -- cdr )
- [ cons>> cdr ] keep quot>> lwhile ;
+M: lazy-while cdr
+ [ cons>> cdr ] keep quot>> lwhile ;
-M: lazy-while nil? ( lazy-while -- bool )
- [ car ] keep quot>> call( elt -- ? ) not ;
+M: lazy-while nil?
+ [ car ] keep quot>> call( elt -- ? ) not ;
TUPLE: lazy-filter cons quot ;
C: <lazy-filter> lazy-filter
-: lfilter ( list quot -- result )
+: lfilter ( list quot: ( elt -- ? ) -- result )
over nil? [ 2drop nil ] [ <lazy-filter> <memoized-cons> ] if ;
-: car-filter? ( lazy-filter -- ? )
+<PRIVATE
+
+: car-filtered? ( lazy-filter -- ? )
[ cons>> car ] [ quot>> ] bi call( elt -- ? ) ;
-: skip ( lazy-filter -- )
- dup cons>> cdr >>cons drop ;
+: skip ( lazy-filter -- lazy-filter )
+ [ cdr ] change-cons ;
+
+PRIVATE>
-M: lazy-filter car ( lazy-filter -- car )
- dup car-filter? [ cons>> ] [ dup skip ] if car ;
+M: lazy-filter car
+ dup car-filtered? [ cons>> ] [ skip ] if car ;
-M: lazy-filter cdr ( lazy-filter -- cdr )
- dup car-filter? [
+M: lazy-filter cdr
+ dup car-filtered? [
[ cons>> cdr ] [ quot>> ] bi lfilter
] [
- dup skip cdr
+ skip cdr
] if ;
-M: lazy-filter nil? ( lazy-filter -- bool )
- dup cons>> nil? [
- drop t
- ] [
- dup car-filter? [
- drop f
- ] [
- dup skip nil?
- ] if
- ] if ;
+M: lazy-filter nil?
+ {
+ { [ dup cons>> nil? ] [ drop t ] }
+ { [ dup car-filtered? ] [ drop f ] }
+ [ skip nil? ]
+ } cond ;
TUPLE: lazy-append list1 list2 ;
C: <lazy-append> lazy-append
-: lappend ( list1 list2 -- result )
+: lappend-lazy ( list1 list2 -- result )
over nil? [ nip ] [ <lazy-append> ] if ;
-M: lazy-append car ( lazy-append -- car )
+M: lazy-append car
list1>> car ;
-M: lazy-append cdr ( lazy-append -- cdr )
- [ list1>> cdr ] keep
- list2>> lappend ;
+M: lazy-append cdr
+ [ list1>> cdr ] [ list2>> ] bi lappend-lazy ;
-M: lazy-append nil? ( lazy-append -- bool )
+M: lazy-append nil?
drop f ;
TUPLE: lazy-from-by n quot ;
-C: lfrom-by lazy-from-by
+: lfrom-by ( n quot: ( n -- o ) -- result ) lazy-from-by boa ; inline
-: lfrom ( n -- list )
- [ 1+ ] lfrom-by ;
+: lfrom ( n -- result )
+ [ 1 + ] lfrom-by ;
-M: lazy-from-by car ( lazy-from-by -- car )
+M: lazy-from-by car
n>> ;
-M: lazy-from-by cdr ( lazy-from-by -- cdr )
- [ n>> ] keep
- quot>> [ call( old -- new ) ] keep lfrom-by ;
+M: lazy-from-by cdr
+ [ n>> ] [ quot>> ] bi [ call( old -- new ) ] keep lfrom-by ;
-M: lazy-from-by nil? ( lazy-from-by -- bool )
+M: lazy-from-by nil?
drop f ;
TUPLE: lazy-zip list1 list2 ;
C: <lazy-zip> lazy-zip
-: lzip ( list1 list2 -- lazy-zip )
- over nil? over nil? or
- [ 2drop nil ] [ <lazy-zip> ] if ;
+: lzip ( list1 list2 -- result )
+ 2dup [ nil? ] either?
+ [ 2drop nil ] [ <lazy-zip> ] if ;
-M: lazy-zip car ( lazy-zip -- car )
- [ list1>> car ] keep list2>> car 2array ;
+M: lazy-zip car
+ [ list1>> car ] keep list2>> car 2array ;
-M: lazy-zip cdr ( lazy-zip -- cdr )
- [ list1>> cdr ] keep list2>> cdr lzip ;
+M: lazy-zip cdr
+ [ list1>> cdr ] keep list2>> cdr lzip ;
-M: lazy-zip nil? ( lazy-zip -- bool )
- drop f ;
+M: lazy-zip nil?
+ drop f ;
TUPLE: sequence-cons index seq ;
C: <sequence-cons> sequence-cons
-: seq>list ( index seq -- list )
+: sequence-tail>list ( index seq -- list )
2dup length >= [
2drop nil
] [
<sequence-cons>
] if ;
-M: sequence-cons car ( sequence-cons -- car )
- [ index>> ] keep
- seq>> nth ;
+M: sequence-cons car
+ [ index>> ] [ seq>> nth ] bi ;
-M: sequence-cons cdr ( sequence-cons -- cdr )
- [ index>> 1+ ] keep
- seq>> seq>list ;
+M: sequence-cons cdr
+ [ index>> 1 + ] [ seq>> sequence-tail>list ] bi ;
-M: sequence-cons nil? ( sequence-cons -- bool )
+M: sequence-cons nil?
drop f ;
-: >list ( object -- list )
- {
- { [ dup sequence? ] [ 0 swap seq>list ] }
- { [ dup list? ] [ ] }
- [ "Could not convert object to a list" throw ]
- } cond ;
+M: sequence >list 0 swap sequence-tail>list ;
TUPLE: lazy-concat car cdr ;
DEFER: lconcat
+<PRIVATE
+
: (lconcat) ( car cdr -- list )
- over nil? [
- nip lconcat
- ] [
- <lazy-concat>
- ] if ;
+ over nil? [ nip lconcat ] [ <lazy-concat> ] if ;
+
+PRIVATE>
: lconcat ( list -- result )
- dup nil? [
- drop nil
- ] [
- uncons (lconcat)
- ] if ;
+ dup nil? [ drop nil ] [ uncons (lconcat) ] if ;
-M: lazy-concat car ( lazy-concat -- car )
+M: lazy-concat car
car>> car ;
-M: lazy-concat cdr ( lazy-concat -- cdr )
+M: lazy-concat cdr
[ car>> cdr ] keep cdr>> (lconcat) ;
-M: lazy-concat nil? ( lazy-concat -- bool )
- dup car>> nil? [
- cdr>> nil?
- ] [
- drop f
- ] if ;
+M: lazy-concat nil?
+ dup car>> nil? [ cdr>> nil? ] [ drop f ] if ;
: lcartesian-product ( list1 list2 -- result )
- swap [ swap [ 2array ] with lazy-map ] with lazy-map lconcat ;
+ swap [ swap [ 2array ] with lmap-lazy ] with lmap-lazy lconcat ;
: lcartesian-product* ( lists -- result )
dup nil? [
drop nil
] [
- [ car ] keep cdr [ car lcartesian-product ] keep cdr list>array swap [
- swap [ swap [ suffix ] with lazy-map ] with lazy-map lconcat
+ uncons
+ [ car lcartesian-product ] [ cdr ] bi
+ list>array swap [
+ swap [ swap [ suffix ] with lmap-lazy ] with lmap-lazy lconcat
] reduce
] if ;
-: lcomp ( list quot -- result )
- [ lcartesian-product* ] dip lazy-map ;
+: lcartesian-map ( list quot: ( elt1 elt2 -- newelt ) -- result )
+ [ lcartesian-product* ] dip [ first2 ] prepose lmap-lazy ;
-: lcomp* ( list guards quot -- result )
- [ [ lcartesian-product* ] dip [ lfilter ] each ] dip lazy-map ;
+: lcartesian-map* ( list guards quot: ( elt1 elt2 -- newelt ) -- result )
+ [ [ [ first2 ] prepose ] map ] [ [ first2 ] prepose ] bi*
+ [ [ lcartesian-product* ] dip [ lfilter ] each ] dip lmap-lazy ;
DEFER: lmerge
-: (lmerge) ( list1 list2 -- result )
- over [ car ] curry -rot
+<PRIVATE
+
+:: (lmerge) ( list1 list2 -- result )
+ [ list1 car ]
[
- dup [ car ] curry -rot
- [
- [ cdr ] bi@ lmerge
- ] 2curry lazy-cons
- ] 2curry lazy-cons ;
+ [ list2 car ]
+ [ list1 cdr list2 cdr lmerge ]
+ lazy-cons
+ ] lazy-cons ;
+
+PRIVATE>
: lmerge ( list1 list2 -- result )
{
- { [ over nil? ] [ nip ] }
- { [ dup nil? ] [ drop ] }
- { [ t ] [ (lmerge) ] }
+ { [ over nil? ] [ nip ] }
+ { [ dup nil? ] [ drop ] }
+ [ (lmerge) ]
} cond ;
TUPLE: lazy-io stream car cdr quot ;
: llines ( stream -- result )
f f [ stream-readln ] <lazy-io> ;
-M: lazy-io car ( lazy-io -- car )
- dup car>> dup [
+M: lazy-io car
+ dup car>> [
nip
] [
- drop dup stream>> over quot>>
- call( stream -- value )
- >>car
- ] if ;
+ dup [ stream>> ] [ quot>> ] bi
+ call( stream -- value ) [ >>car ] [ drop nil ] if*
+ ] if* ;
-M: lazy-io cdr ( lazy-io -- cdr )
+M: lazy-io cdr
dup cdr>> dup [
nip
] [
- drop dup
- [ stream>> ] keep
- [ quot>> ] keep
- car [
+ drop dup [ stream>> ] [ quot>> ] [ car ] tri
+ [
[ f f ] dip <lazy-io> [ >>cdr drop ] keep
] [
3drop nil
] if
] if ;
-M: lazy-io nil? ( lazy-io -- bool )
- car not ;
+M: lazy-io nil?
+ car nil? ;
INSTANCE: sequence-cons list
INSTANCE: memoized-cons list
INSTANCE: promise list
INSTANCE: lazy-io list
INSTANCE: lazy-concat list
-INSTANCE: lazy-cons list
+INSTANCE: lazy-cons-state list
INSTANCE: lazy-map list
INSTANCE: lazy-take list
INSTANCE: lazy-append list
projects / factor.git / blobdiff