1 ! Copyright (C) 2007, 2009 Daniel Ehrenberg.
2 ! See http://factorcode.org/license.txt for BSD license.
3 USING: accessors arrays assocs bit-arrays byte-arrays classes
4 classes.tuple combinators combinators.short-circuit
5 combinators.smart continuations effects generalizations
6 kernel make math math.functions namespaces parser
7 quotations sbufs sequences sequences.generalizations slots
8 splitting stack-checker strings summary vectors words
13 M: fail summary drop "Matching failed" ;
15 : assure ( ? -- ) [ fail ] unless ; inline
17 : =/fail ( obj1 obj2 -- ) = assure ; inline
19 ! Inverse of a quotation
21 : define-inverse ( word quot -- ) "inverse" set-word-prop ;
23 : define-dual ( word1 word2 -- )
24 2dup swap [ 1quotation define-inverse ] 2bi@ ;
26 : define-involution ( word -- ) dup 1quotation define-inverse ;
28 : define-math-inverse ( word quot1 quot2 -- )
29 pick 1quotation 3array "math-inverse" set-word-prop ;
31 :: define-pop-inverse ( word n quot -- )
32 word n "pop-length" set-word-prop
33 word quot "pop-inverse" set-word-prop ;
35 ERROR: bad-math-inverse ;
37 : next ( revquot -- revquot* first )
38 [ bad-math-inverse ] [ unclip-slice ] if-empty ;
40 : constant-word? ( word -- ? )
41 stack-effect [ out>> length 1 = ] [ in>> empty? ] bi and ;
43 : assure-constant ( constant -- quot )
44 dup word? [ bad-math-inverse ] when 1quotation ;
46 : swap-inverse ( math-inverse revquot -- revquot* quot )
47 next assure-constant rot second '[ @ swap @ ] ;
49 : pull-inverse ( math-inverse revquot const -- revquot* quot )
50 assure-constant rot first compose ;
52 : undo-literal ( object -- quot ) [ =/fail ] curry ;
54 PREDICATE: normal-inverse < word "inverse" word-prop >boolean ;
55 PREDICATE: math-inverse < word "math-inverse" word-prop >boolean ;
56 PREDICATE: pop-inverse < word "pop-length" word-prop >boolean ;
57 UNION: explicit-inverse normal-inverse math-inverse pop-inverse ;
59 : enough? ( stack word -- ? )
60 dup deferred? [ 2drop f ] [
61 [ [ length ] [ 1quotation inputs ] bi* >= ]
65 : fold-word ( stack word -- stack )
67 [ 1quotation with-datastack ]
68 [ [ [ literalize , ] each ] [ , ] bi* { } ]
71 : fold ( quot -- folded-quot )
72 [ { } [ fold-word ] reduce % ] [ ] make ;
74 ERROR: no-recursive-inverse ;
78 : flattenable? ( object -- ? )
82 [ explicit-inverse? not ]
85 : flatten ( quot -- expanded )
86 visited get over suffix visited [
90 [ visited get member-eq? [ no-recursive-inverse ] when ]
97 ERROR: undefined-inverse ;
99 GENERIC: inverse ( revquot word -- revquot* quot )
101 M: object inverse undo-literal ;
103 M: symbol inverse undo-literal ;
105 M: word inverse undefined-inverse ;
107 M: normal-inverse inverse
108 "inverse" word-prop ;
110 M: math-inverse inverse
111 "math-inverse" word-prop
112 swap next dup \ swap =
113 [ drop swap-inverse ] [ pull-inverse ] if ;
115 M: pop-inverse inverse
116 [ "pop-length" word-prop cut-slice swap >quotation ]
117 [ "pop-inverse" word-prop ] bi compose call( -- quot ) ;
119 : (undo) ( revquot -- )
120 [ unclip-slice inverse % (undo) ] unless-empty ;
122 : [undo] ( quot -- undo )
123 flatten fold reverse [ (undo) ] [ ] make ;
125 MACRO: undo ( quot -- quot ) [undo] ;
127 ! Inverse of selected words
129 \ swap define-involution
130 \ dup [ [ =/fail ] keep ] define-inverse
131 \ 2dup [ over =/fail over =/fail ] define-inverse
132 \ 3dup [ pick =/fail pick =/fail pick =/fail ] define-inverse
133 \ pick [ [ pick ] dip =/fail ] define-inverse
135 \ bi@ 1 [ [undo] '[ _ bi@ ] ] define-pop-inverse
136 \ tri@ 1 [ [undo] '[ _ tri@ ] ] define-pop-inverse
137 \ bi* 2 [ [ [undo] ] bi@ '[ _ _ bi* ] ] define-pop-inverse
138 \ tri* 3 [ [ [undo] ] tri@ '[ _ _ _ tri* ] ] define-pop-inverse
140 \ not define-involution
141 \ >boolean [ dup { t f } member-eq? assure ] define-inverse
143 \ tuple>array \ >tuple define-dual
144 \ reverse define-involution
146 \ undo 1 [ ] define-pop-inverse
147 \ map 1 [ [undo] '[ dup sequence? assure _ map ] ] define-pop-inverse
149 \ e^ \ log define-dual
150 \ sq \ sqrt define-dual
152 ERROR: missing-literal ;
154 : assert-literal ( n -- n )
155 dup { [ word? ] [ symbol? not ] } 1&&
156 [ missing-literal ] when ;
158 \ + [ - ] [ - ] define-math-inverse
159 \ - [ + ] [ - ] define-math-inverse
160 \ * [ / ] [ / ] define-math-inverse
161 \ / [ * ] [ / ] define-math-inverse
162 \ ^ [ recip ^ ] [ swap [ log ] bi@ / ] define-math-inverse
165 [ assert-literal ] bi@
166 [ swap [ over = ] dip swap [ 2drop f ] [ = [ t ] [ fail ] if ] if ]
171 \ __ [ drop ] define-inverse
173 : both ( object object -- object )
176 \ both [ dup ] define-inverse
183 { >bit-array bit-array? }
185 { >byte-array byte-array? }
188 { >quotation quotation? }
189 } [ '[ dup _ execute assure ] define-inverse ] assoc-each
191 : assure-length ( seq length -- )
192 swap length =/fail ; inline
194 : assure-array ( array -- array )
195 dup array? assure ; inline
197 : undo-narray ( array n -- ... )
199 [ assure-length ] [ firstn ] 2bi ; inline
201 \ 1array [ 1 undo-narray ] define-inverse
202 \ 2array [ 2 undo-narray ] define-inverse
203 \ 3array [ 3 undo-narray ] define-inverse
204 \ 4array [ 4 undo-narray ] define-inverse
205 \ narray 1 [ '[ _ undo-narray ] ] define-pop-inverse
207 \ first [ 1array ] define-inverse
208 \ first2 [ 2array ] define-inverse
209 \ first3 [ 3array ] define-inverse
210 \ first4 [ 4array ] define-inverse
212 \ prefix \ unclip define-dual
213 \ suffix \ unclip-last define-dual
215 \ append 1 [ [ ?tail assure ] curry ] define-pop-inverse
216 \ prepend 1 [ [ ?head assure ] curry ] define-pop-inverse
218 : assure-same-class ( obj1 obj2 -- )
219 [ class-of ] same? assure ; inline
221 \ output>sequence 2 [ [undo] '[ dup _ assure-same-class _ input<sequence ] ] define-pop-inverse
222 \ input<sequence 1 [ [undo] '[ _ { } output>sequence ] ] define-pop-inverse
226 :: undo-if-empty ( result a b -- seq )
227 a call( -- b ) result = [ { } ] [ result b [undo] call( a -- b ) ] if ;
229 :: undo-if* ( result a b -- boolean )
230 b call( -- b ) result = [ f ] [ result a [undo] call( a -- b ) ] if ;
232 \ if-empty 2 [ swap [ undo-if-empty ] 2curry ] define-pop-inverse
234 \ if* 2 [ swap [ undo-if* ] 2curry ] define-pop-inverse
236 ! Constructor inverse
237 : deconstruct-pred ( class -- quot )
238 predicate-def [ dupd call assure ] curry ;
240 : slot-readers ( class -- quot )
241 all-slots [ name>> reader-word 1quotation ] map [ cleave ] curry ;
243 : ?wrapped ( object -- wrapped )
244 dup wrapper? [ wrapped>> ] when ;
246 : boa-inverse ( class -- quot )
247 [ deconstruct-pred ] [ slot-readers ] bi compose ;
249 \ boa 1 [ ?wrapped boa-inverse ] define-pop-inverse
251 : empty-inverse ( class -- quot )
253 [ tuple-slots [ ] any? [ fail ] when ]
256 \ new 1 [ ?wrapped empty-inverse ] define-pop-inverse
258 ! More useful inverse-based combinators
260 : recover-fail ( try fail -- )
263 [ drop call ] [ nip throw ] if
266 : true-out ( quot effect -- quot' )
267 out>> length '[ @ _ ndrop t ] ;
269 : false-recover ( effect -- quot )
270 in>> length [ ndrop f ] curry [ recover-fail ] curry ;
272 : [matches?] ( quot -- undoes?-quot )
273 [undo] dup infer [ true-out ] [ false-recover ] bi curry ;
275 MACRO: matches? ( quot -- quot' ) [matches?] ;
279 M: no-match summary drop "Fall through in switch" ;
281 : recover-chain ( seq -- quot )
282 [ no-match ] [ swap \ recover-fail 3array >quotation ] reduce ;
284 : [switch] ( quot-alist -- quot )
285 [ dup quotation? [ [ ] swap 2array ] when ] map
286 reverse [ [ [undo] ] dip compose ] { } assoc>map
289 MACRO: switch ( quot-alist -- quot ) [switch] ;
291 SYNTAX: INVERSE: scan-word parse-definition define-inverse ;
293 SYNTAX: DUAL: scan-word scan-word define-dual ;