1 ! Copyright (C) 2007, 2008 Slava Pestov, Eduardo Cavazos.
2 ! See http://factorcode.org/license.txt for BSD license.
3 USING: accessors arrays assocs classes classes.tuple combinators
4 fry.private hashtables kernel locals.backend locals.errors
5 locals.types macros.expander make math quotations sequences
6 sequences.generalizations sets words ;
12 ! Step 1: rewrite [| into :> forms, turn
13 ! literals with locals in them into code which constructs
14 ! the literal after pushing locals on the stack
16 GENERIC: rewrite-sugar* ( obj -- )
18 : (rewrite-sugar) ( form -- form' )
19 [ rewrite-sugar* ] [ ] make ;
21 GENERIC: quotation-rewrite ( form -- form' )
23 M: callable quotation-rewrite [ [ rewrite-sugar* ] each ] [ ] make ;
25 : var-defs ( vars -- defs )
26 [ [ ] ] [ <multi-def> 1quotation ] if-empty ;
28 M: lambda quotation-rewrite
29 [ body>> ] [ vars>> var-defs ] bi prepend quotation-rewrite ;
31 M: callable rewrite-sugar* quotation-rewrite , ;
33 M: lambda rewrite-sugar* quotation-rewrite , ;
35 GENERIC: rewrite-literal? ( obj -- ? )
37 M: special rewrite-literal? drop t ;
39 M: sequence rewrite-literal? [ rewrite-literal? ] any? ;
41 M: wrapper rewrite-literal? wrapped>> rewrite-literal? ;
43 M: hashtable rewrite-literal? >alist rewrite-literal? ;
45 M: tuple rewrite-literal? tuple>array rewrite-literal? ;
47 M: object rewrite-literal? drop f ;
49 GENERIC: rewrite-element ( obj -- )
51 : rewrite-elements ( seq -- )
52 [ rewrite-element ] each ;
54 : rewrite-sequence ( seq -- )
55 [ rewrite-elements ] [ length ] [ 0 head ] tri '[ _ _ nsequence ] % ;
57 M: sequence rewrite-element
58 dup rewrite-literal? [ rewrite-sequence ] [ , ] if ;
60 M: hashtable rewrite-element
61 dup rewrite-literal? [ >alist rewrite-sequence \ >hashtable , ] [ , ] if ;
63 M: tuple rewrite-element
64 dup rewrite-literal? [
65 [ tuple-slots rewrite-elements ] [ class-of ] bi '[ _ boa ] %
68 M: quotation rewrite-element rewrite-sugar* ;
70 M: lambda rewrite-element rewrite-sugar* ;
72 M: let rewrite-element let-form-in-literal-error ;
74 M: local rewrite-element , ;
76 M: local-reader rewrite-element , ;
78 M: local-writer rewrite-element local-writer-in-literal-error ;
80 M: word rewrite-element <wrapper> , ;
82 : rewrite-wrapper ( wrapper -- )
83 dup rewrite-literal? [ wrapped>> rewrite-element ] [ , ] if ;
85 M: wrapper rewrite-element
86 rewrite-wrapper \ <wrapper> , ;
88 M: object rewrite-element , ;
90 M: sequence rewrite-sugar* rewrite-element ;
92 M: tuple rewrite-sugar* rewrite-element ;
94 M: multi-def rewrite-sugar* , ;
96 M: hashtable rewrite-sugar* rewrite-element ;
98 M: wrapper rewrite-sugar*
101 M: word rewrite-sugar*
102 dup { load-locals get-local drop-locals } member-eq?
103 [ >r/r>-in-lambda-error ] [ call-next-method ] if ;
105 M: object rewrite-sugar* , ;
107 M: let rewrite-sugar*
108 body>> quotation-rewrite % ;
110 ! Step 2: identify free variables and make them into explicit
111 ! parameters of lambdas which are curried on
113 GENERIC: rewrite-closures* ( obj -- )
115 : (rewrite-closures) ( form -- form' )
116 [ [ rewrite-closures* ] each ] [ ] make ;
118 : rewrite-closures ( form -- form' )
119 expand-macros (rewrite-sugar) (rewrite-closures) point-free ;
121 GENERIC: defs-vars* ( seq form -- seq' )
123 : defs-vars ( form -- vars ) { } [ defs-vars* ] reduce members ;
125 M: multi-def defs-vars* locals>> [ unquote suffix ] each ;
127 M: quotation defs-vars* [ defs-vars* ] each ;
129 M: object defs-vars* drop ;
131 GENERIC: uses-vars* ( seq form -- seq' )
133 : uses-vars ( form -- vars ) { } [ uses-vars* ] reduce members ;
135 M: local-writer uses-vars* "local-reader" word-prop suffix ;
137 M: lexical uses-vars* suffix ;
139 M: quote uses-vars* local>> uses-vars* ;
141 M: object uses-vars* drop ;
143 M: quotation uses-vars* [ uses-vars* ] each ;
145 : free-vars ( form -- seq )
146 [ uses-vars ] [ defs-vars ] bi diff ;
148 M: callable rewrite-closures*
149 ! Turn free variables into bound variables, curry them
151 dup free-vars [ <quote> ] map
153 [ var-defs prepend (rewrite-closures) point-free , ]
154 [ length \ curry <repetition> % ]
157 M: object rewrite-closures* , ;
159 ! Step 3: rewrite locals usage within a single quotation into
160 ! retain stack manipulation
162 : local-index ( args obj -- n )
163 2dup '[ unquote _ eq? ] find drop
164 [ 2nip ] [ bad-local ] if* ;
166 : read-local-quot ( args obj -- quot )
167 local-index neg [ get-local ] curry ;
169 GENERIC: localize ( args obj -- args quot )
171 M: local localize dupd read-local-quot ;
173 M: quote localize dupd local>> read-local-quot ;
175 M: local-reader localize dupd read-local-quot [ local-value ] append ;
177 M: local-writer localize
178 dupd "local-reader" word-prop
179 read-local-quot [ set-local-value ] append ;
181 M: multi-def localize
184 [ [ [ local-reader? ] dip '[ [ 1array ] _ [ndip] ] [ [ ] ] if ] map-index concat ]
187 { [ dup 1 > ] [ [ load-locals ] curry ] }
188 { [ dup 1 = ] [ drop [ load-local ] ] }
193 M: object localize 1quotation ;
195 : drop-locals-quot ( args -- )
196 [ length , [ drop-locals ] % ] unless-empty ;
198 : point-free ( quot -- newquot )
199 [ { } swap [ localize % ] each drop-locals-quot ] [ ] make ;