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1 | ;;;; -*-scheme-*- |
2 | ;;;; | |
f78a1cce LC |
3 | ;;;; Copyright (C) 2001, 2003, 2006, 2009, 2010, 2011, |
4 | ;;;; 2012 Free Software Foundation, Inc. | |
5 | ;;;; | |
73be1d9e MV |
6 | ;;;; This library is free software; you can redistribute it and/or |
7 | ;;;; modify it under the terms of the GNU Lesser General Public | |
8 | ;;;; License as published by the Free Software Foundation; either | |
53befeb7 | 9 | ;;;; version 3 of the License, or (at your option) any later version. |
86b96c16 | 10 | ;;;; |
73be1d9e | 11 | ;;;; This library is distributed in the hope that it will be useful, |
86b96c16 | 12 | ;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of |
73be1d9e MV |
13 | ;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
14 | ;;;; Lesser General Public License for more details. | |
86b96c16 | 15 | ;;;; |
73be1d9e MV |
16 | ;;;; You should have received a copy of the GNU Lesser General Public |
17 | ;;;; License along with this library; if not, write to the Free Software | |
92205699 | 18 | ;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
86b96c16 MD |
19 | ;;;; |
20 | \f | |
21 | ||
a63812a2 | 22 | ;;; Portable implementation of syntax-case |
565c8e30 | 23 | ;;; Originally extracted from Chez Scheme Version 5.9f |
a63812a2 JB |
24 | ;;; Authors: R. Kent Dybvig, Oscar Waddell, Bob Hieb, Carl Bruggeman |
25 | ||
26 | ;;; Copyright (c) 1992-1997 Cadence Research Systems | |
27 | ;;; Permission to copy this software, in whole or in part, to use this | |
28 | ;;; software for any lawful purpose, and to redistribute this software | |
29 | ;;; is granted subject to the restriction that all copies made of this | |
30 | ;;; software must include this copyright notice in full. This software | |
31 | ;;; is provided AS IS, with NO WARRANTY, EITHER EXPRESS OR IMPLIED, | |
32 | ;;; INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY | |
33 | ;;; OR FITNESS FOR ANY PARTICULAR PURPOSE. IN NO EVENT SHALL THE | |
34 | ;;; AUTHORS BE LIABLE FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES OF ANY | |
35 | ;;; NATURE WHATSOEVER. | |
36 | ||
565c8e30 AW |
37 | ;;; Modified by Mikael Djurfeldt <djurfeldt@nada.kth.se> according |
38 | ;;; to the ChangeLog distributed in the same directory as this file: | |
39 | ;;; 1997-08-19, 1997-09-03, 1997-09-10, 2000-08-13, 2000-08-24, | |
40 | ;;; 2000-09-12, 2001-03-08 | |
41 | ||
42 | ;;; Modified by Andy Wingo <wingo@pobox.com> according to the Git | |
43 | ;;; revision control logs corresponding to this file: 2009, 2010. | |
a63812a2 JB |
44 | |
45 | ||
8a73a6d2 | 46 | ;;; This file defines the syntax-case expander, macroexpand, and a set |
a63812a2 JB |
47 | ;;; of associated syntactic forms and procedures. Of these, the |
48 | ;;; following are documented in The Scheme Programming Language, | |
565c8e30 AW |
49 | ;;; Fourth Edition (R. Kent Dybvig, MIT Press, 2009), and in the |
50 | ;;; R6RS: | |
a63812a2 JB |
51 | ;;; |
52 | ;;; bound-identifier=? | |
22225fc1 | 53 | ;;; datum->syntax |
a63812a2 | 54 | ;;; define-syntax |
ea3ca4e4 | 55 | ;;; syntax-parameterize |
a63812a2 JB |
56 | ;;; free-identifier=? |
57 | ;;; generate-temporaries | |
58 | ;;; identifier? | |
59 | ;;; identifier-syntax | |
60 | ;;; let-syntax | |
61 | ;;; letrec-syntax | |
62 | ;;; syntax | |
63 | ;;; syntax-case | |
22225fc1 | 64 | ;;; syntax->datum |
a63812a2 JB |
65 | ;;; syntax-rules |
66 | ;;; with-syntax | |
67 | ;;; | |
565c8e30 AW |
68 | ;;; Additionally, the expander provides definitions for a number of core |
69 | ;;; Scheme syntactic bindings, such as `let', `lambda', and the like. | |
a63812a2 JB |
70 | |
71 | ;;; The remaining exports are listed below: | |
72 | ;;; | |
8a73a6d2 AW |
73 | ;;; (macroexpand datum) |
74 | ;;; if datum represents a valid expression, macroexpand returns an | |
a63812a2 JB |
75 | ;;; expanded version of datum in a core language that includes no |
76 | ;;; syntactic abstractions. The core language includes begin, | |
77 | ;;; define, if, lambda, letrec, quote, and set!. | |
78 | ;;; (eval-when situations expr ...) | |
79 | ;;; conditionally evaluates expr ... at compile-time or run-time | |
80 | ;;; depending upon situations (see the Chez Scheme System Manual, | |
81 | ;;; Revision 3, for a complete description) | |
e4721dde | 82 | ;;; (syntax-violation who message form [subform]) |
a63812a2 | 83 | ;;; used to report errors found during expansion |
5f1a2fb1 | 84 | ;;; ($sc-dispatch e p) |
a63812a2 JB |
85 | ;;; used by expanded code to handle syntax-case matching |
86 | ||
565c8e30 AW |
87 | ;;; This file is shipped along with an expanded version of itself, |
88 | ;;; psyntax-pp.scm, which is loaded when psyntax.scm has not yet been | |
89 | ;;; compiled. In this way, psyntax bootstraps off of an expanded | |
90 | ;;; version of itself. | |
91 | ||
92 | ;;; This implementation of the expander sometimes uses syntactic | |
93 | ;;; abstractions when procedural abstractions would suffice. For | |
94 | ;;; example, we define top-wrap and top-marked? as | |
a63812a2 | 95 | ;;; |
a63812a2 JB |
96 | ;;; (define-syntax top-wrap (identifier-syntax '((top)))) |
97 | ;;; (define-syntax top-marked? | |
98 | ;;; (syntax-rules () | |
99 | ;;; ((_ w) (memq 'top (wrap-marks w))))) | |
565c8e30 | 100 | ;;; |
a63812a2 | 101 | ;;; rather than |
565c8e30 | 102 | ;;; |
a63812a2 JB |
103 | ;;; (define top-wrap '((top))) |
104 | ;;; (define top-marked? | |
105 | ;;; (lambda (w) (memq 'top (wrap-marks w)))) | |
565c8e30 AW |
106 | ;;; |
107 | ;;; On the other hand, we don't do this consistently; we define | |
108 | ;;; make-wrap, wrap-marks, and wrap-subst simply as | |
109 | ;;; | |
a63812a2 JB |
110 | ;;; (define make-wrap cons) |
111 | ;;; (define wrap-marks car) | |
112 | ;;; (define wrap-subst cdr) | |
565c8e30 | 113 | ;;; |
a63812a2 JB |
114 | ;;; In Chez Scheme, the syntactic and procedural forms of these |
115 | ;;; abstractions are equivalent, since the optimizer consistently | |
565c8e30 AW |
116 | ;;; integrates constants and small procedures. This will be true of |
117 | ;;; Guile as well, once we implement a proper inliner. | |
a63812a2 | 118 | |
a63812a2 | 119 | |
565c8e30 | 120 | ;;; Implementation notes: |
a63812a2 JB |
121 | |
122 | ;;; Objects with no standard print syntax, including objects containing | |
123 | ;;; cycles and syntax object, are allowed in quoted data as long as they | |
22225fc1 | 124 | ;;; are contained within a syntax form or produced by datum->syntax. |
a63812a2 JB |
125 | ;;; Such objects are never copied. |
126 | ||
127 | ;;; All identifiers that don't have macro definitions and are not bound | |
565c8e30 | 128 | ;;; lexically are assumed to be global variables. |
a63812a2 JB |
129 | |
130 | ;;; Top-level definitions of macro-introduced identifiers are allowed. | |
131 | ;;; This may not be appropriate for implementations in which the | |
132 | ;;; model is that bindings are created by definitions, as opposed to | |
133 | ;;; one in which initial values are assigned by definitions. | |
134 | ||
a63812a2 | 135 | ;;; Identifiers and syntax objects are implemented as vectors for |
565c8e30 | 136 | ;;; portability. As a result, it is possible to "forge" syntax objects. |
a63812a2 | 137 | |
565c8e30 AW |
138 | ;;; The implementation of generate-temporaries assumes that it is |
139 | ;;; possible to generate globally unique symbols (gensyms). | |
a63812a2 | 140 | |
565c8e30 AW |
141 | ;;; The source location associated with incoming expressions is tracked |
142 | ;;; via the source-properties mechanism, a weak map from expression to | |
143 | ;;; source information. At times the source is separated from the | |
144 | ;;; expression; see the note below about "efficiency and confusion". | |
a96434cc | 145 | |
a63812a2 JB |
146 | |
147 | ;;; Bootstrapping: | |
148 | ||
149 | ;;; When changing syntax-object representations, it is necessary to support | |
150 | ;;; both old and new syntax-object representations in id-var-name. It | |
151 | ;;; should be sufficient to recognize old representations and treat | |
152 | ;;; them as not lexically bound. | |
153 | ||
154 | ||
155 | ||
9c35c579 AW |
156 | (eval-when (compile) |
157 | (set-current-module (resolve-module '(guile)))) | |
158 | ||
a63812a2 | 159 | (let () |
8fad25c2 AW |
160 | (define-syntax define-expansion-constructors |
161 | (lambda (x) | |
162 | (syntax-case x () | |
163 | ((_) | |
164 | (let lp ((n 0) (out '())) | |
165 | (if (< n (vector-length %expanded-vtables)) | |
166 | (lp (1+ n) | |
167 | (let* ((vtable (vector-ref %expanded-vtables n)) | |
168 | (stem (struct-ref vtable (+ vtable-offset-user 0))) | |
169 | (fields (struct-ref vtable (+ vtable-offset-user 2))) | |
170 | (sfields (map (lambda (f) (datum->syntax x f)) fields)) | |
171 | (ctor (datum->syntax x (symbol-append 'make- stem)))) | |
172 | (cons #`(define (#,ctor #,@sfields) | |
173 | (make-struct (vector-ref %expanded-vtables #,n) 0 | |
174 | #,@sfields)) | |
175 | out))) | |
176 | #`(begin #,@(reverse out)))))))) | |
177 | ||
178 | (define-syntax define-expansion-accessors | |
179 | (lambda (x) | |
180 | (syntax-case x () | |
181 | ((_ stem field ...) | |
182 | (let lp ((n 0)) | |
183 | (let ((vtable (vector-ref %expanded-vtables n)) | |
184 | (stem (syntax->datum #'stem))) | |
185 | (if (eq? (struct-ref vtable (+ vtable-offset-user 0)) stem) | |
186 | #`(begin | |
187 | (define (#,(datum->syntax x (symbol-append stem '?)) x) | |
188 | (and (struct? x) | |
189 | (eq? (struct-vtable x) | |
190 | (vector-ref %expanded-vtables #,n)))) | |
191 | #,@(map | |
192 | (lambda (f) | |
193 | (let ((get (datum->syntax x (symbol-append stem '- f))) | |
194 | (set (datum->syntax x (symbol-append 'set- stem '- f '!))) | |
195 | (idx (list-index (struct-ref vtable | |
196 | (+ vtable-offset-user 2)) | |
197 | f))) | |
198 | #`(begin | |
199 | (define (#,get x) | |
200 | (struct-ref x #,idx)) | |
201 | (define (#,set x v) | |
202 | (struct-set! x #,idx v))))) | |
203 | (syntax->datum #'(field ...)))) | |
204 | (lp (1+ n))))))))) | |
205 | ||
206 | (define-syntax define-structure | |
207 | (lambda (x) | |
208 | (define construct-name | |
209 | (lambda (template-identifier . args) | |
210 | (datum->syntax | |
211 | template-identifier | |
212 | (string->symbol | |
a63812a2 JB |
213 | (apply string-append |
214 | (map (lambda (x) | |
215 | (if (string? x) | |
216 | x | |
22225fc1 | 217 | (symbol->string (syntax->datum x)))) |
a63812a2 | 218 | args)))))) |
8fad25c2 AW |
219 | (syntax-case x () |
220 | ((_ (name id1 ...)) | |
221 | (and-map identifier? #'(name id1 ...)) | |
222 | (with-syntax | |
223 | ((constructor (construct-name #'name "make-" #'name)) | |
224 | (predicate (construct-name #'name #'name "?")) | |
225 | ((access ...) | |
226 | (map (lambda (x) (construct-name x #'name "-" x)) | |
227 | #'(id1 ...))) | |
228 | ((assign ...) | |
229 | (map (lambda (x) | |
230 | (construct-name x "set-" #'name "-" x "!")) | |
231 | #'(id1 ...))) | |
232 | (structure-length | |
233 | (+ (length #'(id1 ...)) 1)) | |
234 | ((index ...) | |
235 | (let f ((i 1) (ids #'(id1 ...))) | |
236 | (if (null? ids) | |
237 | '() | |
238 | (cons i (f (+ i 1) (cdr ids))))))) | |
239 | #'(begin | |
240 | (define constructor | |
241 | (lambda (id1 ...) | |
242 | (vector 'name id1 ... ))) | |
243 | (define predicate | |
244 | (lambda (x) | |
245 | (and (vector? x) | |
246 | (= (vector-length x) structure-length) | |
247 | (eq? (vector-ref x 0) 'name)))) | |
248 | (define access | |
249 | (lambda (x) | |
250 | (vector-ref x index))) | |
251 | ... | |
252 | (define assign | |
253 | (lambda (x update) | |
254 | (vector-set! x index update))) | |
255 | ...)))))) | |
a63812a2 | 256 | |
8fad25c2 AW |
257 | (let () |
258 | (define-expansion-constructors) | |
259 | (define-expansion-accessors lambda meta) | |
260 | ||
261 | ;; hooks to nonportable run-time helpers | |
262 | (begin | |
d8f699e8 AW |
263 | (define-syntax fx+ (identifier-syntax +)) |
264 | (define-syntax fx- (identifier-syntax -)) | |
265 | (define-syntax fx= (identifier-syntax =)) | |
266 | (define-syntax fx< (identifier-syntax <)) | |
8fad25c2 AW |
267 | |
268 | (define top-level-eval-hook | |
269 | (lambda (x mod) | |
270 | (primitive-eval x))) | |
271 | ||
272 | (define local-eval-hook | |
273 | (lambda (x mod) | |
274 | (primitive-eval x))) | |
bdf7759c | 275 | |
f9685f43 AW |
276 | ;; Capture syntax-session-id before we shove it off into a module. |
277 | (define session-id | |
278 | (let ((v (module-variable (current-module) 'syntax-session-id))) | |
279 | (lambda () | |
280 | ((variable-ref v))))) | |
c3ae0ed4 | 281 | |
8fad25c2 AW |
282 | (define put-global-definition-hook |
283 | (lambda (symbol type val) | |
284 | (module-define! (current-module) | |
285 | symbol | |
286 | (make-syntax-transformer symbol type val)))) | |
e809758a | 287 | |
8fad25c2 AW |
288 | (define get-global-definition-hook |
289 | (lambda (symbol module) | |
290 | (if (and (not module) (current-module)) | |
291 | (warn "module system is booted, we should have a module" symbol)) | |
292 | (let ((v (module-variable (if module | |
293 | (resolve-module (cdr module)) | |
294 | (current-module)) | |
295 | symbol))) | |
296 | (and v (variable-bound? v) | |
297 | (let ((val (variable-ref v))) | |
298 | (and (macro? val) (macro-type val) | |
299 | (cons (macro-type val) | |
300 | (macro-binding val))))))))) | |
301 | ||
302 | ||
303 | (define (decorate-source e s) | |
32fbc38f | 304 | (if (and s (supports-source-properties? e)) |
8fad25c2 AW |
305 | (set-source-properties! e s)) |
306 | e) | |
307 | ||
308 | (define (maybe-name-value! name val) | |
309 | (if (lambda? val) | |
310 | (let ((meta (lambda-meta val))) | |
311 | (if (not (assq 'name meta)) | |
312 | (set-lambda-meta! val (acons 'name name meta)))))) | |
313 | ||
314 | ;; output constructors | |
315 | (define build-void | |
316 | (lambda (source) | |
317 | (make-void source))) | |
318 | ||
7081d4f9 | 319 | (define build-call |
8fad25c2 | 320 | (lambda (source fun-exp arg-exps) |
7081d4f9 | 321 | (make-call source fun-exp arg-exps))) |
bdf7759c | 322 | |
8fad25c2 AW |
323 | (define build-conditional |
324 | (lambda (source test-exp then-exp else-exp) | |
325 | (make-conditional source test-exp then-exp else-exp))) | |
bdf7759c | 326 | |
8fad25c2 AW |
327 | (define build-dynlet |
328 | (lambda (source fluids vals body) | |
329 | (make-dynlet source fluids vals body))) | |
bdf7759c | 330 | |
8fad25c2 AW |
331 | (define build-lexical-reference |
332 | (lambda (type source name var) | |
333 | (make-lexical-ref source name var))) | |
bdf7759c | 334 | |
8fad25c2 AW |
335 | (define build-lexical-assignment |
336 | (lambda (source name var exp) | |
337 | (maybe-name-value! name exp) | |
338 | (make-lexical-set source name var exp))) | |
bdf7759c | 339 | |
8fad25c2 AW |
340 | (define (analyze-variable mod var modref-cont bare-cont) |
341 | (if (not mod) | |
342 | (bare-cont var) | |
343 | (let ((kind (car mod)) | |
344 | (mod (cdr mod))) | |
345 | (case kind | |
346 | ((public) (modref-cont mod var #t)) | |
347 | ((private) (if (not (equal? mod (module-name (current-module)))) | |
348 | (modref-cont mod var #f) | |
349 | (bare-cont var))) | |
350 | ((bare) (bare-cont var)) | |
351 | ((hygiene) (if (and (not (equal? mod (module-name (current-module)))) | |
352 | (module-variable (resolve-module mod) var)) | |
353 | (modref-cont mod var #f) | |
354 | (bare-cont var))) | |
355 | (else (syntax-violation #f "bad module kind" var mod)))))) | |
356 | ||
357 | (define build-global-reference | |
358 | (lambda (source var mod) | |
359 | (analyze-variable | |
360 | mod var | |
361 | (lambda (mod var public?) | |
362 | (make-module-ref source mod var public?)) | |
363 | (lambda (var) | |
364 | (make-toplevel-ref source var))))) | |
365 | ||
366 | (define build-global-assignment | |
367 | (lambda (source var exp mod) | |
368 | (maybe-name-value! var exp) | |
369 | (analyze-variable | |
370 | mod var | |
371 | (lambda (mod var public?) | |
372 | (make-module-set source mod var public? exp)) | |
373 | (lambda (var) | |
374 | (make-toplevel-set source var exp))))) | |
375 | ||
376 | (define build-global-definition | |
377 | (lambda (source var exp) | |
378 | (maybe-name-value! var exp) | |
379 | (make-toplevel-define source var exp))) | |
380 | ||
381 | (define build-simple-lambda | |
382 | (lambda (src req rest vars meta exp) | |
383 | (make-lambda src | |
384 | meta | |
385 | ;; hah, a case in which kwargs would be nice. | |
386 | (make-lambda-case | |
387 | ;; src req opt rest kw inits vars body else | |
388 | src req #f rest #f '() vars exp #f)))) | |
389 | ||
390 | (define build-case-lambda | |
391 | (lambda (src meta body) | |
392 | (make-lambda src meta body))) | |
393 | ||
394 | (define build-lambda-case | |
395 | ;; req := (name ...) | |
396 | ;; opt := (name ...) | #f | |
397 | ;; rest := name | #f | |
398 | ;; kw := (allow-other-keys? (keyword name var) ...) | #f | |
399 | ;; inits: (init ...) | |
400 | ;; vars: (sym ...) | |
401 | ;; vars map to named arguments in the following order: | |
402 | ;; required, optional (positional), rest, keyword. | |
403 | ;; the body of a lambda: anything, already expanded | |
404 | ;; else: lambda-case | #f | |
405 | (lambda (src req opt rest kw inits vars body else-case) | |
406 | (make-lambda-case src req opt rest kw inits vars body else-case))) | |
407 | ||
a881a4ae AW |
408 | (define build-primcall |
409 | (lambda (src name args) | |
410 | (make-primcall src name args))) | |
411 | ||
8fad25c2 AW |
412 | (define build-primref |
413 | (lambda (src name) | |
a881a4ae AW |
414 | (make-primitive-ref src name))) |
415 | ||
8fad25c2 AW |
416 | (define (build-data src exp) |
417 | (make-const src exp)) | |
418 | ||
419 | (define build-sequence | |
420 | (lambda (src exps) | |
421 | (if (null? (cdr exps)) | |
422 | (car exps) | |
6fc3eae4 | 423 | (make-seq src (car exps) (build-sequence #f (cdr exps)))))) |
8fad25c2 AW |
424 | |
425 | (define build-let | |
426 | (lambda (src ids vars val-exps body-exp) | |
427 | (for-each maybe-name-value! ids val-exps) | |
428 | (if (null? vars) | |
429 | body-exp | |
430 | (make-let src ids vars val-exps body-exp)))) | |
431 | ||
432 | (define build-named-let | |
433 | (lambda (src ids vars val-exps body-exp) | |
434 | (let ((f (car vars)) | |
435 | (f-name (car ids)) | |
436 | (vars (cdr vars)) | |
437 | (ids (cdr ids))) | |
438 | (let ((proc (build-simple-lambda src ids #f vars '() body-exp))) | |
439 | (maybe-name-value! f-name proc) | |
22cf27c8 | 440 | (for-each maybe-name-value! ids val-exps) |
8fad25c2 AW |
441 | (make-letrec |
442 | src #f | |
443 | (list f-name) (list f) (list proc) | |
7081d4f9 AW |
444 | (build-call src (build-lexical-reference 'fun src f-name f) |
445 | val-exps)))))) | |
8fad25c2 AW |
446 | |
447 | (define build-letrec | |
448 | (lambda (src in-order? ids vars val-exps body-exp) | |
449 | (if (null? vars) | |
450 | body-exp | |
451 | (begin | |
452 | (for-each maybe-name-value! ids val-exps) | |
453 | (make-letrec src in-order? ids vars val-exps body-exp))))) | |
454 | ||
455 | ||
456 | ;; FIXME: use a faster gensym | |
1bbe0a63 | 457 | (define-syntax-rule (build-lexical-var src id) |
f9685f43 | 458 | (gensym (string-append (symbol->string id) "-"))) |
bdf7759c | 459 | |
8fad25c2 | 460 | (define-structure (syntax-object expression wrap module)) |
a63812a2 | 461 | |
8fad25c2 | 462 | (define-syntax no-source (identifier-syntax #f)) |
a63812a2 | 463 | |
8fad25c2 AW |
464 | (define source-annotation |
465 | (lambda (x) | |
32fbc38f MW |
466 | (let ((props (source-properties |
467 | (if (syntax-object? x) | |
468 | (syntax-object-expression x) | |
469 | x)))) | |
470 | (and (pair? props) props)))) | |
a63812a2 | 471 | |
1bbe0a63 AW |
472 | (define-syntax-rule (arg-check pred? e who) |
473 | (let ((x e)) | |
474 | (if (not (pred? x)) (syntax-violation who "invalid argument" x)))) | |
8fad25c2 AW |
475 | |
476 | ;; compile-time environments | |
477 | ||
478 | ;; wrap and environment comprise two level mapping. | |
479 | ;; wrap : id --> label | |
480 | ;; env : label --> <element> | |
481 | ||
482 | ;; environments are represented in two parts: a lexical part and a global | |
483 | ;; part. The lexical part is a simple list of associations from labels | |
484 | ;; to bindings. The global part is implemented by | |
485 | ;; {put,get}-global-definition-hook and associates symbols with | |
486 | ;; bindings. | |
487 | ||
488 | ;; global (assumed global variable) and displaced-lexical (see below) | |
489 | ;; do not show up in any environment; instead, they are fabricated by | |
c070de63 | 490 | ;; resolve-identifier when it finds no other bindings. |
8fad25c2 AW |
491 | |
492 | ;; <environment> ::= ((<label> . <binding>)*) | |
493 | ||
494 | ;; identifier bindings include a type and a value | |
495 | ||
496 | ;; <binding> ::= (macro . <procedure>) macros | |
5b36d603 | 497 | ;; (syntax-parameter . (<procedure>)) syntax parameters |
8fad25c2 AW |
498 | ;; (core . <procedure>) core forms |
499 | ;; (module-ref . <procedure>) @ or @@ | |
500 | ;; (begin) begin | |
501 | ;; (define) define | |
502 | ;; (define-syntax) define-syntax | |
c2d822de | 503 | ;; (define-syntax-parameter) define-syntax-parameter |
8fad25c2 AW |
504 | ;; (local-syntax . rec?) let-syntax/letrec-syntax |
505 | ;; (eval-when) eval-when | |
4c2e13e5 | 506 | ;; (syntax . (<var> . <level>)) pattern variables |
8fad25c2 AW |
507 | ;; (global) assumed global variable |
508 | ;; (lexical . <var>) lexical variables | |
509 | ;; (displaced-lexical) displaced lexicals | |
510 | ;; <level> ::= <nonnegative integer> | |
511 | ;; <var> ::= variable returned by build-lexical-var | |
512 | ||
c2d822de AW |
513 | ;; a macro is a user-defined syntactic-form. a core is a |
514 | ;; system-defined syntactic form. begin, define, define-syntax, | |
515 | ;; define-syntax-parameter, and eval-when are treated specially | |
516 | ;; since they are sensitive to whether the form is at top-level and | |
517 | ;; (except for eval-when) can denote valid internal definitions. | |
8fad25c2 AW |
518 | |
519 | ;; a pattern variable is a variable introduced by syntax-case and can | |
520 | ;; be referenced only within a syntax form. | |
521 | ||
522 | ;; any identifier for which no top-level syntax definition or local | |
523 | ;; binding of any kind has been seen is assumed to be a global | |
524 | ;; variable. | |
525 | ||
526 | ;; a lexical variable is a lambda- or letrec-bound variable. | |
527 | ||
528 | ;; a displaced-lexical identifier is a lexical identifier removed from | |
529 | ;; it's scope by the return of a syntax object containing the identifier. | |
530 | ;; a displaced lexical can also appear when a letrec-syntax-bound | |
531 | ;; keyword is referenced on the rhs of one of the letrec-syntax clauses. | |
532 | ;; a displaced lexical should never occur with properly written macros. | |
533 | ||
534 | (define-syntax make-binding | |
535 | (syntax-rules (quote) | |
536 | ((_ type value) (cons type value)) | |
537 | ((_ 'type) '(type)) | |
538 | ((_ type) (cons type '())))) | |
1bbe0a63 AW |
539 | (define-syntax-rule (binding-type x) |
540 | (car x)) | |
541 | (define-syntax-rule (binding-value x) | |
542 | (cdr x)) | |
8fad25c2 AW |
543 | |
544 | (define-syntax null-env (identifier-syntax '())) | |
545 | ||
546 | (define extend-env | |
547 | (lambda (labels bindings r) | |
548 | (if (null? labels) | |
549 | r | |
550 | (extend-env (cdr labels) (cdr bindings) | |
551 | (cons (cons (car labels) (car bindings)) r))))) | |
c3ae0ed4 | 552 | |
8fad25c2 AW |
553 | (define extend-var-env |
554 | ;; variant of extend-env that forms "lexical" binding | |
555 | (lambda (labels vars r) | |
556 | (if (null? labels) | |
557 | r | |
558 | (extend-var-env (cdr labels) (cdr vars) | |
559 | (cons (cons (car labels) (make-binding 'lexical (car vars))) r))))) | |
560 | ||
561 | ;; we use a "macros only" environment in expansion of local macro | |
562 | ;; definitions so that their definitions can use local macros without | |
563 | ;; attempting to use other lexical identifiers. | |
564 | (define macros-only-env | |
565 | (lambda (r) | |
566 | (if (null? r) | |
567 | '() | |
568 | (let ((a (car r))) | |
5b36d603 | 569 | (if (memq (cadr a) '(macro syntax-parameter)) |
8fad25c2 AW |
570 | (cons a (macros-only-env (cdr r))) |
571 | (macros-only-env (cdr r))))))) | |
572 | ||
8fad25c2 AW |
573 | (define global-extend |
574 | (lambda (type sym val) | |
575 | (put-global-definition-hook sym type val))) | |
576 | ||
577 | ||
578 | ;; Conceptually, identifiers are always syntax objects. Internally, | |
579 | ;; however, the wrap is sometimes maintained separately (a source of | |
580 | ;; efficiency and confusion), so that symbols are also considered | |
581 | ;; identifiers by id?. Externally, they are always wrapped. | |
582 | ||
583 | (define nonsymbol-id? | |
584 | (lambda (x) | |
585 | (and (syntax-object? x) | |
586 | (symbol? (syntax-object-expression x))))) | |
587 | ||
588 | (define id? | |
589 | (lambda (x) | |
590 | (cond | |
591 | ((symbol? x) #t) | |
592 | ((syntax-object? x) (symbol? (syntax-object-expression x))) | |
593 | (else #f)))) | |
594 | ||
1bbe0a63 AW |
595 | (define-syntax-rule (id-sym-name e) |
596 | (let ((x e)) | |
597 | (if (syntax-object? x) | |
598 | (syntax-object-expression x) | |
599 | x))) | |
8fad25c2 AW |
600 | |
601 | (define id-sym-name&marks | |
602 | (lambda (x w) | |
603 | (if (syntax-object? x) | |
604 | (values | |
c3ae0ed4 | 605 | (syntax-object-expression x) |
8fad25c2 AW |
606 | (join-marks (wrap-marks w) (wrap-marks (syntax-object-wrap x)))) |
607 | (values x (wrap-marks w))))) | |
c3ae0ed4 | 608 | |
8fad25c2 AW |
609 | ;; syntax object wraps |
610 | ||
1948b38d MW |
611 | ;; <wrap> ::= ((<mark> ...) . (<subst> ...)) |
612 | ;; <subst> ::= shift | <subs> | |
613 | ;; <subs> ::= #(ribcage #(<sym> ...) #(<mark> ...) #(<label> ...)) | |
614 | ;; | #(ribcage (<sym> ...) (<mark> ...) (<label> ...)) | |
8fad25c2 | 615 | |
381ccb0b AW |
616 | (define-syntax make-wrap (identifier-syntax cons)) |
617 | (define-syntax wrap-marks (identifier-syntax car)) | |
618 | (define-syntax wrap-subst (identifier-syntax cdr)) | |
8fad25c2 | 619 | |
8fad25c2 AW |
620 | ;; labels must be comparable with "eq?", have read-write invariance, |
621 | ;; and distinct from symbols. | |
f9685f43 AW |
622 | (define (gen-label) |
623 | (string-append "l-" (session-id) (symbol->string (gensym "-")))) | |
8fad25c2 AW |
624 | |
625 | (define gen-labels | |
626 | (lambda (ls) | |
627 | (if (null? ls) | |
628 | '() | |
629 | (cons (gen-label) (gen-labels (cdr ls)))))) | |
630 | ||
631 | (define-structure (ribcage symnames marks labels)) | |
632 | ||
633 | (define-syntax empty-wrap (identifier-syntax '(()))) | |
634 | ||
635 | (define-syntax top-wrap (identifier-syntax '((top)))) | |
636 | ||
1bbe0a63 AW |
637 | (define-syntax-rule (top-marked? w) |
638 | (memq 'top (wrap-marks w))) | |
8fad25c2 AW |
639 | |
640 | ;; Marks must be comparable with "eq?" and distinct from pairs and | |
641 | ;; the symbol top. We do not use integers so that marks will remain | |
642 | ;; unique even across file compiles. | |
643 | ||
644 | (define-syntax the-anti-mark (identifier-syntax #f)) | |
645 | ||
646 | (define anti-mark | |
647 | (lambda (w) | |
648 | (make-wrap (cons the-anti-mark (wrap-marks w)) | |
649 | (cons 'shift (wrap-subst w))))) | |
650 | ||
1bbe0a63 | 651 | (define-syntax-rule (new-mark) |
f9685f43 | 652 | (gensym (string-append "m-" (session-id) "-"))) |
8fad25c2 AW |
653 | |
654 | ;; make-empty-ribcage and extend-ribcage maintain list-based ribcages for | |
655 | ;; internal definitions, in which the ribcages are built incrementally | |
1bbe0a63 AW |
656 | (define-syntax-rule (make-empty-ribcage) |
657 | (make-ribcage '() '() '())) | |
8fad25c2 AW |
658 | |
659 | (define extend-ribcage! | |
660 | ;; must receive ids with complete wraps | |
661 | (lambda (ribcage id label) | |
662 | (set-ribcage-symnames! ribcage | |
663 | (cons (syntax-object-expression id) | |
664 | (ribcage-symnames ribcage))) | |
665 | (set-ribcage-marks! ribcage | |
666 | (cons (wrap-marks (syntax-object-wrap id)) | |
667 | (ribcage-marks ribcage))) | |
668 | (set-ribcage-labels! ribcage | |
669 | (cons label (ribcage-labels ribcage))))) | |
670 | ||
671 | ;; make-binding-wrap creates vector-based ribcages | |
672 | (define make-binding-wrap | |
673 | (lambda (ids labels w) | |
674 | (if (null? ids) | |
675 | w | |
c3ae0ed4 | 676 | (make-wrap |
8fad25c2 AW |
677 | (wrap-marks w) |
678 | (cons | |
679 | (let ((labelvec (list->vector labels))) | |
680 | (let ((n (vector-length labelvec))) | |
681 | (let ((symnamevec (make-vector n)) (marksvec (make-vector n))) | |
682 | (let f ((ids ids) (i 0)) | |
683 | (if (not (null? ids)) | |
684 | (call-with-values | |
685 | (lambda () (id-sym-name&marks (car ids) w)) | |
686 | (lambda (symname marks) | |
687 | (vector-set! symnamevec i symname) | |
688 | (vector-set! marksvec i marks) | |
689 | (f (cdr ids) (fx+ i 1)))))) | |
690 | (make-ribcage symnamevec marksvec labelvec)))) | |
691 | (wrap-subst w)))))) | |
692 | ||
693 | (define smart-append | |
694 | (lambda (m1 m2) | |
695 | (if (null? m2) | |
696 | m1 | |
697 | (append m1 m2)))) | |
698 | ||
699 | (define join-wraps | |
700 | (lambda (w1 w2) | |
701 | (let ((m1 (wrap-marks w1)) (s1 (wrap-subst w1))) | |
702 | (if (null? m1) | |
703 | (if (null? s1) | |
704 | w2 | |
705 | (make-wrap | |
706 | (wrap-marks w2) | |
707 | (smart-append s1 (wrap-subst w2)))) | |
708 | (make-wrap | |
709 | (smart-append m1 (wrap-marks w2)) | |
710 | (smart-append s1 (wrap-subst w2))))))) | |
711 | ||
712 | (define join-marks | |
713 | (lambda (m1 m2) | |
714 | (smart-append m1 m2))) | |
715 | ||
716 | (define same-marks? | |
717 | (lambda (x y) | |
718 | (or (eq? x y) | |
719 | (and (not (null? x)) | |
720 | (not (null? y)) | |
721 | (eq? (car x) (car y)) | |
722 | (same-marks? (cdr x) (cdr y)))))) | |
723 | ||
724 | (define id-var-name | |
c070de63 AW |
725 | ;; Syntax objects use wraps to associate names with marked |
726 | ;; identifiers. This function returns the name corresponding to | |
727 | ;; the given identifier and wrap, or the original identifier if no | |
728 | ;; corresponding name was found. | |
729 | ;; | |
730 | ;; The name may be a string created by gen-label, indicating a | |
731 | ;; lexical binding, or another syntax object, indicating a | |
732 | ;; reference to a top-level definition created during a previous | |
733 | ;; macroexpansion. | |
734 | ;; | |
47e9919d AW |
735 | ;; For lexical variables, finding a label simply amounts to |
736 | ;; looking for an entry with the same symbolic name and the same | |
737 | ;; marks. Finding a toplevel definition is the same, except we | |
738 | ;; also have to compare modules, hence the `mod' parameter. | |
739 | ;; Instead of adding a separate entry in the ribcage for modules, | |
740 | ;; which wouldn't be used for lexicals, we arrange for the entry | |
741 | ;; for the name entry to be a pair with the module in its car, and | |
742 | ;; the name itself in the cdr. So if the name that we find is a | |
743 | ;; pair, we have to check modules. | |
744 | ;; | |
c070de63 AW |
745 | ;; The identifer may be passed in wrapped or unwrapped. In any |
746 | ;; case, this routine returns either a symbol, a syntax object, or | |
747 | ;; a string label. | |
748 | ;; | |
47e9919d | 749 | (lambda (id w mod) |
1bbe0a63 AW |
750 | (define-syntax-rule (first e) |
751 | ;; Rely on Guile's multiple-values truncation. | |
752 | e) | |
8fad25c2 | 753 | (define search |
47e9919d | 754 | (lambda (sym subst marks mod) |
8fad25c2 AW |
755 | (if (null? subst) |
756 | (values #f marks) | |
757 | (let ((fst (car subst))) | |
758 | (if (eq? fst 'shift) | |
47e9919d | 759 | (search sym (cdr subst) (cdr marks) mod) |
8fad25c2 AW |
760 | (let ((symnames (ribcage-symnames fst))) |
761 | (if (vector? symnames) | |
47e9919d AW |
762 | (search-vector-rib sym subst marks symnames fst mod) |
763 | (search-list-rib sym subst marks symnames fst mod)))))))) | |
8fad25c2 | 764 | (define search-list-rib |
47e9919d | 765 | (lambda (sym subst marks symnames ribcage mod) |
8fad25c2 | 766 | (let f ((symnames symnames) (i 0)) |
c3ae0ed4 | 767 | (cond |
47e9919d | 768 | ((null? symnames) (search sym (cdr subst) marks mod)) |
8fad25c2 AW |
769 | ((and (eq? (car symnames) sym) |
770 | (same-marks? marks (list-ref (ribcage-marks ribcage) i))) | |
47e9919d AW |
771 | (let ((n (list-ref (ribcage-labels ribcage) i))) |
772 | (if (pair? n) | |
773 | (if (equal? mod (car n)) | |
774 | (values (cdr n) marks) | |
775 | (f (cdr symnames) (fx+ i 1))) | |
776 | (values n marks)))) | |
8fad25c2 AW |
777 | (else (f (cdr symnames) (fx+ i 1))))))) |
778 | (define search-vector-rib | |
47e9919d | 779 | (lambda (sym subst marks symnames ribcage mod) |
8fad25c2 AW |
780 | (let ((n (vector-length symnames))) |
781 | (let f ((i 0)) | |
782 | (cond | |
47e9919d | 783 | ((fx= i n) (search sym (cdr subst) marks mod)) |
8fad25c2 AW |
784 | ((and (eq? (vector-ref symnames i) sym) |
785 | (same-marks? marks (vector-ref (ribcage-marks ribcage) i))) | |
47e9919d AW |
786 | (let ((n (vector-ref (ribcage-labels ribcage) i))) |
787 | (if (pair? n) | |
788 | (if (equal? mod (car n)) | |
789 | (values (cdr n) marks) | |
790 | (f (fx+ i 1))) | |
791 | (values n marks)))) | |
8fad25c2 AW |
792 | (else (f (fx+ i 1)))))))) |
793 | (cond | |
794 | ((symbol? id) | |
47e9919d | 795 | (or (first (search id (wrap-subst w) (wrap-marks w) mod)) id)) |
8fad25c2 AW |
796 | ((syntax-object? id) |
797 | (let ((id (syntax-object-expression id)) | |
47e9919d AW |
798 | (w1 (syntax-object-wrap id)) |
799 | (mod (syntax-object-module id))) | |
8fad25c2 | 800 | (let ((marks (join-marks (wrap-marks w) (wrap-marks w1)))) |
47e9919d | 801 | (call-with-values (lambda () (search id (wrap-subst w) marks mod)) |
8fad25c2 AW |
802 | (lambda (new-id marks) |
803 | (or new-id | |
47e9919d | 804 | (first (search id (wrap-subst w1) marks mod)) |
8fad25c2 AW |
805 | id)))))) |
806 | (else (syntax-violation 'id-var-name "invalid id" id))))) | |
807 | ||
3d51e57c AW |
808 | ;; A helper procedure for syntax-locally-bound-identifiers, which |
809 | ;; itself is a helper for transformer procedures. | |
810 | ;; `locally-bound-identifiers' returns a list of all bindings | |
811 | ;; visible to a syntax object with the given wrap. They are in | |
812 | ;; order from outer to inner. | |
813 | ;; | |
814 | ;; The purpose of this procedure is to give a transformer procedure | |
815 | ;; references on bound identifiers, that the transformer can then | |
816 | ;; introduce some of them in its output. As such, the identifiers | |
817 | ;; are anti-marked, so that rebuild-macro-output doesn't apply new | |
818 | ;; marks to them. | |
819 | ;; | |
820 | (define locally-bound-identifiers | |
821 | (lambda (w mod) | |
822 | (define scan | |
823 | (lambda (subst results) | |
824 | (if (null? subst) | |
825 | results | |
826 | (let ((fst (car subst))) | |
827 | (if (eq? fst 'shift) | |
828 | (scan (cdr subst) results) | |
829 | (let ((symnames (ribcage-symnames fst)) | |
830 | (marks (ribcage-marks fst))) | |
831 | (if (vector? symnames) | |
832 | (scan-vector-rib subst symnames marks results) | |
833 | (scan-list-rib subst symnames marks results)))))))) | |
834 | (define scan-list-rib | |
835 | (lambda (subst symnames marks results) | |
836 | (let f ((symnames symnames) (marks marks) (results results)) | |
837 | (if (null? symnames) | |
838 | (scan (cdr subst) results) | |
839 | (f (cdr symnames) (cdr marks) | |
840 | (cons (wrap (car symnames) | |
841 | (anti-mark (make-wrap (car marks) subst)) | |
842 | mod) | |
843 | results)))))) | |
844 | (define scan-vector-rib | |
845 | (lambda (subst symnames marks results) | |
846 | (let ((n (vector-length symnames))) | |
847 | (let f ((i 0) (results results)) | |
848 | (if (fx= i n) | |
849 | (scan (cdr subst) results) | |
850 | (f (fx+ i 1) | |
851 | (cons (wrap (vector-ref symnames i) | |
852 | (anti-mark (make-wrap (vector-ref marks i) subst)) | |
853 | mod) | |
854 | results))))))) | |
855 | (scan (wrap-subst w) '()))) | |
856 | ||
5b36d603 AW |
857 | ;; Returns three values: binding type, binding value, the module (for |
858 | ;; resolving toplevel vars). | |
859 | (define (resolve-identifier id w r mod resolve-syntax-parameters?) | |
860 | (define (resolve-syntax-parameters b) | |
861 | (if (and resolve-syntax-parameters? | |
862 | (eq? (binding-type b) 'syntax-parameter)) | |
863 | (or (assq-ref r (binding-value b)) | |
864 | (make-binding 'macro (car (binding-value b)))) | |
865 | b)) | |
c070de63 | 866 | (define (resolve-global var mod) |
5b36d603 AW |
867 | (let ((b (resolve-syntax-parameters |
868 | (or (get-global-definition-hook var mod) | |
869 | (make-binding 'global))))) | |
870 | (if (eq? (binding-type b) 'global) | |
871 | (values 'global var mod) | |
872 | (values (binding-type b) (binding-value b) mod)))) | |
c070de63 | 873 | (define (resolve-lexical label mod) |
5b36d603 AW |
874 | (let ((b (resolve-syntax-parameters |
875 | (or (assq-ref r label) | |
876 | (make-binding 'displaced-lexical))))) | |
877 | (values (binding-type b) (binding-value b) mod))) | |
47e9919d | 878 | (let ((n (id-var-name id w mod))) |
c070de63 AW |
879 | (cond |
880 | ((syntax-object? n) | |
ea3ca4e4 | 881 | ;; Recursing allows syntax-parameterize to override |
5b36d603 AW |
882 | ;; macro-introduced syntax parameters. |
883 | (resolve-identifier n w r mod resolve-syntax-parameters?)) | |
c070de63 AW |
884 | ((symbol? n) |
885 | (resolve-global n (if (syntax-object? id) | |
886 | (syntax-object-module id) | |
887 | mod))) | |
888 | ((string? n) | |
889 | (resolve-lexical n (if (syntax-object? id) | |
890 | (syntax-object-module id) | |
891 | mod))) | |
892 | (else | |
893 | (error "unexpected id-var-name" id w n))))) | |
894 | ||
9b0975f1 AW |
895 | (define transformer-environment |
896 | (make-fluid | |
897 | (lambda (k) | |
898 | (error "called outside the dynamic extent of a syntax transformer")))) | |
899 | ||
900 | (define (with-transformer-environment k) | |
901 | ((fluid-ref transformer-environment) k)) | |
902 | ||
8fad25c2 AW |
903 | ;; free-id=? must be passed fully wrapped ids since (free-id=? x y) |
904 | ;; may be true even if (free-id=? (wrap x w) (wrap y w)) is not. | |
905 | ||
906 | (define free-id=? | |
907 | (lambda (i j) | |
47e9919d AW |
908 | (let* ((mi (and (syntax-object? i) (syntax-object-module i))) |
909 | (mj (and (syntax-object? j) (syntax-object-module j))) | |
910 | (ni (id-var-name i empty-wrap mi)) | |
911 | (nj (id-var-name j empty-wrap mj))) | |
912 | (define (id-module-binding id mod) | |
913 | (module-variable | |
914 | (if mod | |
915 | ;; The normal case. | |
916 | (resolve-module (cdr mod)) | |
917 | ;; Either modules have not been booted, or we have a | |
918 | ;; raw symbol coming in, which is possible. | |
919 | (current-module)) | |
920 | (id-sym-name id))) | |
c070de63 AW |
921 | (cond |
922 | ((syntax-object? ni) (free-id=? ni j)) | |
923 | ((syntax-object? nj) (free-id=? i nj)) | |
924 | ((symbol? ni) | |
925 | ;; `i' is not lexically bound. Assert that `j' is free, | |
926 | ;; and if so, compare their bindings, that they are either | |
927 | ;; bound to the same variable, or both unbound and have | |
928 | ;; the same name. | |
929 | (and (eq? nj (id-sym-name j)) | |
47e9919d | 930 | (let ((bi (id-module-binding i mi))) |
c070de63 | 931 | (if bi |
47e9919d AW |
932 | (eq? bi (id-module-binding j mj)) |
933 | (and (not (id-module-binding j mj)) | |
c070de63 | 934 | (eq? ni nj)))) |
47e9919d | 935 | (eq? (id-module-binding i mi) (id-module-binding j mj)))) |
c070de63 AW |
936 | (else |
937 | ;; Otherwise `i' is bound, so check that `j' is bound, and | |
938 | ;; bound to the same thing. | |
939 | (equal? ni nj)))))) | |
04b04af8 | 940 | |
8fad25c2 AW |
941 | ;; bound-id=? may be passed unwrapped (or partially wrapped) ids as |
942 | ;; long as the missing portion of the wrap is common to both of the ids | |
943 | ;; since (bound-id=? x y) iff (bound-id=? (wrap x w) (wrap y w)) | |
944 | ||
945 | (define bound-id=? | |
946 | (lambda (i j) | |
947 | (if (and (syntax-object? i) (syntax-object? j)) | |
948 | (and (eq? (syntax-object-expression i) | |
949 | (syntax-object-expression j)) | |
950 | (same-marks? (wrap-marks (syntax-object-wrap i)) | |
951 | (wrap-marks (syntax-object-wrap j)))) | |
952 | (eq? i j)))) | |
953 | ||
954 | ;; "valid-bound-ids?" returns #t if it receives a list of distinct ids. | |
955 | ;; valid-bound-ids? may be passed unwrapped (or partially wrapped) ids | |
956 | ;; as long as the missing portion of the wrap is common to all of the | |
957 | ;; ids. | |
958 | ||
959 | (define valid-bound-ids? | |
960 | (lambda (ids) | |
961 | (and (let all-ids? ((ids ids)) | |
962 | (or (null? ids) | |
963 | (and (id? (car ids)) | |
964 | (all-ids? (cdr ids))))) | |
965 | (distinct-bound-ids? ids)))) | |
966 | ||
967 | ;; distinct-bound-ids? expects a list of ids and returns #t if there are | |
968 | ;; no duplicates. It is quadratic on the length of the id list; long | |
969 | ;; lists could be sorted to make it more efficient. distinct-bound-ids? | |
970 | ;; may be passed unwrapped (or partially wrapped) ids as long as the | |
971 | ;; missing portion of the wrap is common to all of the ids. | |
972 | ||
973 | (define distinct-bound-ids? | |
974 | (lambda (ids) | |
975 | (let distinct? ((ids ids)) | |
976 | (or (null? ids) | |
977 | (and (not (bound-id-member? (car ids) (cdr ids))) | |
978 | (distinct? (cdr ids))))))) | |
979 | ||
980 | (define bound-id-member? | |
981 | (lambda (x list) | |
982 | (and (not (null? list)) | |
983 | (or (bound-id=? x (car list)) | |
984 | (bound-id-member? x (cdr list)))))) | |
985 | ||
986 | ;; wrapping expressions and identifiers | |
987 | ||
988 | (define wrap | |
989 | (lambda (x w defmod) | |
990 | (cond | |
991 | ((and (null? (wrap-marks w)) (null? (wrap-subst w))) x) | |
992 | ((syntax-object? x) | |
993 | (make-syntax-object | |
994 | (syntax-object-expression x) | |
995 | (join-wraps w (syntax-object-wrap x)) | |
996 | (syntax-object-module x))) | |
997 | ((null? x) x) | |
998 | (else (make-syntax-object x w defmod))))) | |
999 | ||
1000 | (define source-wrap | |
1001 | (lambda (x w s defmod) | |
1002 | (wrap (decorate-source x s) w defmod))) | |
1003 | ||
1004 | ;; expanding | |
1005 | ||
78a47455 | 1006 | (define expand-sequence |
8fad25c2 AW |
1007 | (lambda (body r w s mod) |
1008 | (build-sequence s | |
1009 | (let dobody ((body body) (r r) (w w) (mod mod)) | |
1010 | (if (null? body) | |
1011 | '() | |
78a47455 | 1012 | (let ((first (expand (car body) r w mod))) |
8fad25c2 AW |
1013 | (cons first (dobody (cdr body) r w mod)))))))) |
1014 | ||
4da326f2 | 1015 | ;; At top-level, we allow mixed definitions and expressions. Like |
78a47455 | 1016 | ;; expand-body we expand in two passes. |
4da326f2 AW |
1017 | ;; |
1018 | ;; First, from left to right, we expand just enough to know what | |
1019 | ;; expressions are definitions, syntax definitions, and splicing | |
1020 | ;; statements (`begin'). If we anything needs evaluating at | |
1021 | ;; expansion-time, it is expanded directly. | |
1022 | ;; | |
1023 | ;; Otherwise we collect expressions to expand, in thunks, and then | |
1024 | ;; expand them all at the end. This allows all syntax expanders | |
1025 | ;; visible in a toplevel sequence to be visible during the | |
1026 | ;; expansions of all normal definitions and expressions in the | |
1027 | ;; sequence. | |
1028 | ;; | |
78a47455 | 1029 | (define expand-top-sequence |
8fad25c2 | 1030 | (lambda (body r w s m esew mod) |
45f58467 AW |
1031 | (let* ((r (cons '("placeholder" . (placeholder)) r)) |
1032 | (ribcage (make-empty-ribcage)) | |
1033 | (w (make-wrap (wrap-marks w) (cons ribcage (wrap-subst w))))) | |
19ef14f9 AW |
1034 | (define (record-definition! id var) |
1035 | (let ((mod (cons 'hygiene (module-name (current-module))))) | |
47e9919d AW |
1036 | ;; Ribcages map symbol+marks to names, mostly for |
1037 | ;; resolving lexicals. Here to add a mapping for toplevel | |
1038 | ;; definitions we also need to match the module. So, we | |
1039 | ;; put it in the name instead, and make id-var-name handle | |
1040 | ;; the special case of names that are pairs. See the | |
1041 | ;; comments in id-var-name for more. | |
1042 | (extend-ribcage! ribcage id | |
1043 | (cons (syntax-object-module id) | |
1044 | (wrap var top-wrap mod))))) | |
de41e564 AW |
1045 | (define (macro-introduced-identifier? id) |
1046 | (not (equal? (wrap-marks (syntax-object-wrap id)) '(top)))) | |
1047 | (define (fresh-derived-name id orig-form) | |
1048 | (symbol-append | |
1049 | (syntax-object-expression id) | |
1050 | '- | |
1051 | (string->symbol | |
1052 | ;; FIXME: `hash' currently stops descending into nested | |
1053 | ;; data at some point, so it's less unique than we would | |
1054 | ;; like. Also this encodes hash values into the ABI of | |
1055 | ;; compiled modules; a problem? | |
1056 | (number->string | |
1057 | (hash (syntax->datum orig-form) most-positive-fixnum) | |
1058 | 16)))) | |
45f58467 AW |
1059 | (define (parse body r w s m esew mod) |
1060 | (let lp ((body body) (exps '())) | |
1061 | (if (null? body) | |
1062 | exps | |
1063 | (lp (cdr body) | |
1064 | (append (parse1 (car body) r w s m esew mod) | |
1065 | exps))))) | |
1066 | (define (parse1 x r w s m esew mod) | |
1067 | (call-with-values | |
1068 | (lambda () | |
1069 | (syntax-type x r w (source-annotation x) ribcage mod #f)) | |
dfadcf85 | 1070 | (lambda (type value form e w s mod) |
45f58467 AW |
1071 | (case type |
1072 | ((define-form) | |
1073 | (let* ((id (wrap value w mod)) | |
1074 | (label (gen-label)) | |
de41e564 AW |
1075 | (var (if (macro-introduced-identifier? id) |
1076 | (fresh-derived-name id x) | |
1077 | (syntax-object-expression id)))) | |
45f58467 AW |
1078 | (record-definition! id var) |
1079 | (list | |
1080 | (if (eq? m 'c&e) | |
b2208d2e | 1081 | (let ((x (build-global-definition s var (expand e r w mod)))) |
45f58467 AW |
1082 | (top-level-eval-hook x mod) |
1083 | (lambda () x)) | |
1084 | (lambda () | |
b2208d2e | 1085 | (build-global-definition s var (expand e r w mod))))))) |
c2d822de | 1086 | ((define-syntax-form define-syntax-parameter-form) |
45f58467 AW |
1087 | (let* ((id (wrap value w mod)) |
1088 | (label (gen-label)) | |
de41e564 AW |
1089 | (var (if (macro-introduced-identifier? id) |
1090 | (fresh-derived-name id x) | |
1091 | (syntax-object-expression id)))) | |
45f58467 AW |
1092 | (record-definition! id var) |
1093 | (case m | |
1094 | ((c) | |
1095 | (cond | |
1096 | ((memq 'compile esew) | |
b2208d2e | 1097 | (let ((e (expand-install-global var type (expand e r w mod)))) |
45f58467 AW |
1098 | (top-level-eval-hook e mod) |
1099 | (if (memq 'load esew) | |
1100 | (list (lambda () e)) | |
1101 | '()))) | |
1102 | ((memq 'load esew) | |
1103 | (list (lambda () | |
b2208d2e | 1104 | (expand-install-global var type (expand e r w mod))))) |
45f58467 AW |
1105 | (else '()))) |
1106 | ((c&e) | |
b2208d2e | 1107 | (let ((e (expand-install-global var type (expand e r w mod)))) |
45f58467 AW |
1108 | (top-level-eval-hook e mod) |
1109 | (list (lambda () e)))) | |
1110 | (else | |
1111 | (if (memq 'eval esew) | |
1112 | (top-level-eval-hook | |
b2208d2e | 1113 | (expand-install-global var type (expand e r w mod)) |
45f58467 AW |
1114 | mod)) |
1115 | '())))) | |
1116 | ((begin-form) | |
1117 | (syntax-case e () | |
1118 | ((_ e1 ...) | |
1119 | (parse #'(e1 ...) r w s m esew mod)))) | |
1120 | ((local-syntax-form) | |
b2208d2e | 1121 | (expand-local-syntax value e r w s mod |
45f58467 AW |
1122 | (lambda (forms r w s mod) |
1123 | (parse forms r w s m esew mod)))) | |
1124 | ((eval-when-form) | |
1125 | (syntax-case e () | |
1126 | ((_ (x ...) e1 e2 ...) | |
b2208d2e | 1127 | (let ((when-list (parse-when-list e #'(x ...))) |
45f58467 AW |
1128 | (body #'(e1 e2 ...))) |
1129 | (define (recurse m esew) | |
1130 | (parse body r w s m esew mod)) | |
1131 | (cond | |
1132 | ((eq? m 'e) | |
1133 | (if (memq 'eval when-list) | |
1134 | (recurse (if (memq 'expand when-list) 'c&e 'e) | |
1135 | '(eval)) | |
1136 | (begin | |
1137 | (if (memq 'expand when-list) | |
1138 | (top-level-eval-hook | |
b2208d2e | 1139 | (expand-top-sequence body r w s 'e '(eval) mod) |
45f58467 AW |
1140 | mod)) |
1141 | '()))) | |
1142 | ((memq 'load when-list) | |
1143 | (if (or (memq 'compile when-list) | |
1144 | (memq 'expand when-list) | |
1145 | (and (eq? m 'c&e) (memq 'eval when-list))) | |
1146 | (recurse 'c&e '(compile load)) | |
1147 | (if (memq m '(c c&e)) | |
1148 | (recurse 'c '(load)) | |
1149 | '()))) | |
1150 | ((or (memq 'compile when-list) | |
1151 | (memq 'expand when-list) | |
1152 | (and (eq? m 'c&e) (memq 'eval when-list))) | |
1153 | (top-level-eval-hook | |
b2208d2e | 1154 | (expand-top-sequence body r w s 'e '(eval) mod) |
45f58467 AW |
1155 | mod) |
1156 | '()) | |
1157 | (else | |
1158 | '())))))) | |
1159 | (else | |
1160 | (list | |
1161 | (if (eq? m 'c&e) | |
dfadcf85 | 1162 | (let ((x (expand-expr type value form e r w s mod))) |
45f58467 AW |
1163 | (top-level-eval-hook x mod) |
1164 | (lambda () x)) | |
1165 | (lambda () | |
dfadcf85 | 1166 | (expand-expr type value form e r w s mod))))))))) |
45f58467 AW |
1167 | (let ((exps (map (lambda (x) (x)) |
1168 | (reverse (parse body r w s m esew mod))))) | |
1169 | (if (null? exps) | |
1170 | (build-void s) | |
1171 | (build-sequence s exps)))))) | |
4c2e13e5 | 1172 | |
78a47455 | 1173 | (define expand-install-global |
5b36d603 | 1174 | (lambda (name type e) |
8fad25c2 AW |
1175 | (build-global-definition |
1176 | no-source | |
1177 | name | |
a881a4ae | 1178 | (build-primcall |
8fad25c2 | 1179 | no-source |
a881a4ae | 1180 | 'make-syntax-transformer |
5b36d603 AW |
1181 | (if (eq? type 'define-syntax-parameter-form) |
1182 | (list (build-data no-source name) | |
1183 | (build-data no-source 'syntax-parameter) | |
1184 | (build-primcall no-source 'list (list e))) | |
1185 | (list (build-data no-source name) | |
1186 | (build-data no-source 'macro) | |
1187 | e)))))) | |
1188 | ||
440ac793 AW |
1189 | (define parse-when-list |
1190 | (lambda (e when-list) | |
aa5698fb AW |
1191 | ;; `when-list' is syntax'd version of list of situations. We |
1192 | ;; could match these keywords lexically, via free-id=?, but then | |
1193 | ;; we twingle the definition of eval-when to the bindings of | |
1194 | ;; eval, load, expand, and compile, which is totally unintended. | |
1195 | ;; So do a symbolic match instead. | |
440ac793 AW |
1196 | (let ((result (strip when-list empty-wrap))) |
1197 | (let lp ((l result)) | |
1198 | (if (null? l) | |
1199 | result | |
1200 | (if (memq (car l) '(compile load eval expand)) | |
1201 | (lp (cdr l)) | |
1202 | (syntax-violation 'eval-when "invalid situation" e | |
1203 | (car l)))))))) | |
8fad25c2 | 1204 | |
40e92f09 MW |
1205 | ;; syntax-type returns seven values: type, value, form, e, w, s, and |
1206 | ;; mod. The first two are described in the table below. | |
8fad25c2 AW |
1207 | ;; |
1208 | ;; type value explanation | |
1209 | ;; ------------------------------------------------------------------- | |
1210 | ;; core procedure core singleton | |
1211 | ;; core-form procedure core form | |
1212 | ;; module-ref procedure @ or @@ singleton | |
1213 | ;; lexical name lexical variable reference | |
1214 | ;; global name global variable reference | |
1215 | ;; begin none begin keyword | |
1216 | ;; define none define keyword | |
1217 | ;; define-syntax none define-syntax keyword | |
c2d822de | 1218 | ;; define-syntax-parameter none define-syntax-parameter keyword |
8fad25c2 AW |
1219 | ;; local-syntax rec? letrec-syntax/let-syntax keyword |
1220 | ;; eval-when none eval-when keyword | |
1221 | ;; syntax level pattern variable | |
1222 | ;; displaced-lexical none displaced lexical identifier | |
1223 | ;; lexical-call name call to lexical variable | |
1224 | ;; global-call name call to global variable | |
1225 | ;; call none any other call | |
1226 | ;; begin-form none begin expression | |
1227 | ;; define-form id variable definition | |
1228 | ;; define-syntax-form id syntax definition | |
c2d822de | 1229 | ;; define-syntax-parameter-form id syntax parameter definition |
8fad25c2 AW |
1230 | ;; local-syntax-form rec? syntax definition |
1231 | ;; eval-when-form none eval-when form | |
1232 | ;; constant none self-evaluating datum | |
1233 | ;; other none anything else | |
1234 | ;; | |
40e92f09 MW |
1235 | ;; form is the entire form. For definition forms (define-form, |
1236 | ;; define-syntax-form, and define-syntax-parameter-form), e is the | |
1237 | ;; rhs expression. For all others, e is the entire form. w is the | |
1238 | ;; wrap for both form and e. s is the source for the entire form. | |
1239 | ;; mod is the module for both form and e. | |
8fad25c2 | 1240 | ;; |
c2d822de AW |
1241 | ;; syntax-type expands macros and unwraps as necessary to get to one |
1242 | ;; of the forms above. It also parses definition forms, although | |
1243 | ;; perhaps this should be done by the consumer. | |
8fad25c2 AW |
1244 | |
1245 | (define syntax-type | |
1246 | (lambda (e r w s rib mod for-car?) | |
1247 | (cond | |
1248 | ((symbol? e) | |
5b36d603 AW |
1249 | (call-with-values (lambda () (resolve-identifier e w r mod #t)) |
1250 | (lambda (type value mod*) | |
c070de63 AW |
1251 | (case type |
1252 | ((macro) | |
1253 | (if for-car? | |
dfadcf85 | 1254 | (values type value e e w s mod) |
b2208d2e | 1255 | (syntax-type (expand-macro value e r w s rib mod) |
c070de63 AW |
1256 | r empty-wrap s rib mod #f))) |
1257 | ((global) | |
1258 | ;; Toplevel definitions may resolve to bindings with | |
1259 | ;; different names or in different modules. | |
dfadcf85 AW |
1260 | (values type value e value w s mod*)) |
1261 | (else (values type value e e w s mod)))))) | |
8fad25c2 AW |
1262 | ((pair? e) |
1263 | (let ((first (car e))) | |
1264 | (call-with-values | |
1265 | (lambda () (syntax-type first r w s rib mod #t)) | |
40e92f09 | 1266 | (lambda (ftype fval fform fe fw fs fmod) |
8fad25c2 AW |
1267 | (case ftype |
1268 | ((lexical) | |
40e92f09 | 1269 | (values 'lexical-call fval e e w s mod)) |
8fad25c2 AW |
1270 | ((global) |
1271 | ;; If we got here via an (@@ ...) expansion, we need to | |
1272 | ;; make sure the fmod information is propagated back | |
1273 | ;; correctly -- hence this consing. | |
1274 | (values 'global-call (make-syntax-object fval w fmod) | |
40e92f09 | 1275 | e e w s mod)) |
8fad25c2 | 1276 | ((macro) |
78a47455 | 1277 | (syntax-type (expand-macro fval e r w s rib mod) |
8fad25c2 AW |
1278 | r empty-wrap s rib mod for-car?)) |
1279 | ((module-ref) | |
1280 | (call-with-values (lambda () (fval e r w)) | |
1281 | (lambda (e r w s mod) | |
1282 | (syntax-type e r w s rib mod for-car?)))) | |
1283 | ((core) | |
40e92f09 | 1284 | (values 'core-form fval e e w s mod)) |
8fad25c2 | 1285 | ((local-syntax) |
40e92f09 | 1286 | (values 'local-syntax-form fval e e w s mod)) |
8fad25c2 | 1287 | ((begin) |
40e92f09 | 1288 | (values 'begin-form #f e e w s mod)) |
8fad25c2 | 1289 | ((eval-when) |
40e92f09 | 1290 | (values 'eval-when-form #f e e w s mod)) |
8fad25c2 AW |
1291 | ((define) |
1292 | (syntax-case e () | |
1293 | ((_ name val) | |
1294 | (id? #'name) | |
40e92f09 | 1295 | (values 'define-form #'name e #'val w s mod)) |
8fad25c2 AW |
1296 | ((_ (name . args) e1 e2 ...) |
1297 | (and (id? #'name) | |
1298 | (valid-bound-ids? (lambda-var-list #'args))) | |
1299 | ;; need lambda here... | |
1300 | (values 'define-form (wrap #'name w mod) | |
40e92f09 | 1301 | (wrap e w mod) |
8fad25c2 AW |
1302 | (decorate-source |
1303 | (cons #'lambda (wrap #'(args e1 e2 ...) w mod)) | |
1304 | s) | |
1305 | empty-wrap s mod)) | |
1306 | ((_ name) | |
1307 | (id? #'name) | |
1308 | (values 'define-form (wrap #'name w mod) | |
40e92f09 | 1309 | (wrap e w mod) |
8fad25c2 AW |
1310 | #'(if #f #f) |
1311 | empty-wrap s mod)))) | |
1312 | ((define-syntax) | |
1313 | (syntax-case e () | |
1314 | ((_ name val) | |
1315 | (id? #'name) | |
40e92f09 | 1316 | (values 'define-syntax-form #'name e #'val w s mod)))) |
c2d822de AW |
1317 | ((define-syntax-parameter) |
1318 | (syntax-case e () | |
1319 | ((_ name val) | |
1320 | (id? #'name) | |
40e92f09 | 1321 | (values 'define-syntax-parameter-form #'name e #'val w s mod)))) |
8fad25c2 | 1322 | (else |
40e92f09 | 1323 | (values 'call #f e e w s mod))))))) |
8fad25c2 AW |
1324 | ((syntax-object? e) |
1325 | (syntax-type (syntax-object-expression e) | |
1326 | r | |
1327 | (join-wraps w (syntax-object-wrap e)) | |
1328 | (or (source-annotation e) s) rib | |
1329 | (or (syntax-object-module e) mod) for-car?)) | |
40e92f09 MW |
1330 | ((self-evaluating? e) (values 'constant #f e e w s mod)) |
1331 | (else (values 'other #f e e w s mod))))) | |
8fad25c2 | 1332 | |
78a47455 | 1333 | (define expand |
8fad25c2 AW |
1334 | (lambda (e r w mod) |
1335 | (call-with-values | |
1336 | (lambda () (syntax-type e r w (source-annotation e) #f mod #f)) | |
40e92f09 MW |
1337 | (lambda (type value form e w s mod) |
1338 | (expand-expr type value form e r w s mod))))) | |
8fad25c2 | 1339 | |
78a47455 | 1340 | (define expand-expr |
40e92f09 | 1341 | (lambda (type value form e r w s mod) |
8fad25c2 AW |
1342 | (case type |
1343 | ((lexical) | |
1344 | (build-lexical-reference 'value s e value)) | |
1345 | ((core core-form) | |
1346 | ;; apply transformer | |
1347 | (value e r w s mod)) | |
1348 | ((module-ref) | |
1349 | (call-with-values (lambda () (value e r w)) | |
1350 | (lambda (e r w s mod) | |
78a47455 | 1351 | (expand e r w mod)))) |
8fad25c2 | 1352 | ((lexical-call) |
b2208d2e | 1353 | (expand-call |
8fad25c2 AW |
1354 | (let ((id (car e))) |
1355 | (build-lexical-reference 'fun (source-annotation id) | |
1356 | (if (syntax-object? id) | |
1357 | (syntax->datum id) | |
1358 | id) | |
1359 | value)) | |
1360 | e r w s mod)) | |
1361 | ((global-call) | |
b2208d2e | 1362 | (expand-call |
8fad25c2 AW |
1363 | (build-global-reference (source-annotation (car e)) |
1364 | (if (syntax-object? value) | |
1365 | (syntax-object-expression value) | |
1366 | value) | |
1367 | (if (syntax-object? value) | |
1368 | (syntax-object-module value) | |
1369 | mod)) | |
1370 | e r w s mod)) | |
1371 | ((constant) (build-data s (strip (source-wrap e w s mod) empty-wrap))) | |
1372 | ((global) (build-global-reference s value mod)) | |
b2208d2e | 1373 | ((call) (expand-call (expand (car e) r w mod) e r w s mod)) |
8fad25c2 AW |
1374 | ((begin-form) |
1375 | (syntax-case e () | |
dc65d1cf AW |
1376 | ((_ e1 e2 ...) (expand-sequence #'(e1 e2 ...) r w s mod)) |
1377 | ((_) | |
0bdd4351 AW |
1378 | (syntax-violation #f "sequence of zero expressions" |
1379 | (source-wrap e w s mod))))) | |
8fad25c2 | 1380 | ((local-syntax-form) |
78a47455 | 1381 | (expand-local-syntax value e r w s mod expand-sequence)) |
8fad25c2 AW |
1382 | ((eval-when-form) |
1383 | (syntax-case e () | |
1384 | ((_ (x ...) e1 e2 ...) | |
440ac793 | 1385 | (let ((when-list (parse-when-list e #'(x ...)))) |
8fad25c2 | 1386 | (if (memq 'eval when-list) |
78a47455 AW |
1387 | (expand-sequence #'(e1 e2 ...) r w s mod) |
1388 | (expand-void)))))) | |
c2d822de | 1389 | ((define-form define-syntax-form define-syntax-parameter-form) |
40e92f09 MW |
1390 | (syntax-violation #f "definition in expression context, where definitions are not allowed," |
1391 | (source-wrap form w s mod))) | |
8fad25c2 AW |
1392 | ((syntax) |
1393 | (syntax-violation #f "reference to pattern variable outside syntax form" | |
1394 | (source-wrap e w s mod))) | |
1395 | ((displaced-lexical) | |
1396 | (syntax-violation #f "reference to identifier outside its scope" | |
1397 | (source-wrap e w s mod))) | |
1398 | (else (syntax-violation #f "unexpected syntax" | |
1399 | (source-wrap e w s mod)))))) | |
1400 | ||
b2208d2e | 1401 | (define expand-call |
8fad25c2 AW |
1402 | (lambda (x e r w s mod) |
1403 | (syntax-case e () | |
1404 | ((e0 e1 ...) | |
7081d4f9 | 1405 | (build-call s x |
b2208d2e | 1406 | (map (lambda (e) (expand e r w mod)) #'(e1 ...))))))) |
8fad25c2 AW |
1407 | |
1408 | ;; (What follows is my interpretation of what's going on here -- Andy) | |
1409 | ;; | |
1410 | ;; A macro takes an expression, a tree, the leaves of which are identifiers | |
1411 | ;; and datums. Identifiers are symbols along with a wrap and a module. For | |
1412 | ;; efficiency, subtrees that share wraps and modules may be grouped as one | |
1413 | ;; syntax object. | |
c3ae0ed4 | 1414 | ;; |
8fad25c2 AW |
1415 | ;; Going into the expansion, the expression is given an anti-mark, which |
1416 | ;; logically propagates to all leaves. Then, in the new expression returned | |
1417 | ;; from the transfomer, if we see an expression with an anti-mark, we know it | |
1418 | ;; pertains to the original expression; conversely, expressions without the | |
1419 | ;; anti-mark are known to be introduced by the transformer. | |
c3ae0ed4 | 1420 | ;; |
8fad25c2 AW |
1421 | ;; OK, good until now. We know this algorithm does lexical scoping |
1422 | ;; appropriately because it's widely known in the literature, and psyntax is | |
1423 | ;; widely used. But what about modules? Here we're on our own. What we do is | |
1424 | ;; to mark the module of expressions produced by a macro as pertaining to the | |
1425 | ;; module that was current when the macro was defined -- that is, free | |
1426 | ;; identifiers introduced by a macro are scoped in the macro's module, not in | |
1427 | ;; the expansion's module. Seems to work well. | |
c3ae0ed4 | 1428 | ;; |
8fad25c2 AW |
1429 | ;; The only wrinkle is when we want a macro to expand to code in another |
1430 | ;; module, as is the case for the r6rs `library' form -- the body expressions | |
1431 | ;; should be scoped relative the the new module, the one defined by the macro. | |
1432 | ;; For that, use `(@@ mod-name body)'. | |
c3ae0ed4 | 1433 | ;; |
8fad25c2 AW |
1434 | ;; Part of the macro output will be from the site of the macro use and part |
1435 | ;; from the macro definition. We allow source information from the macro use | |
1436 | ;; to pass through, but we annotate the parts coming from the macro with the | |
1437 | ;; source location information corresponding to the macro use. It would be | |
1438 | ;; really nice if we could also annotate introduced expressions with the | |
1439 | ;; locations corresponding to the macro definition, but that is not yet | |
1440 | ;; possible. | |
78a47455 | 1441 | (define expand-macro |
8fad25c2 AW |
1442 | (lambda (p e r w s rib mod) |
1443 | (define rebuild-macro-output | |
1444 | (lambda (x m) | |
1445 | (cond ((pair? x) | |
1446 | (decorate-source | |
1447 | (cons (rebuild-macro-output (car x) m) | |
1448 | (rebuild-macro-output (cdr x) m)) | |
1449 | s)) | |
1450 | ((syntax-object? x) | |
1451 | (let ((w (syntax-object-wrap x))) | |
30398e94 | 1452 | (let ((ms (wrap-marks w)) (ss (wrap-subst w))) |
8fad25c2 AW |
1453 | (if (and (pair? ms) (eq? (car ms) the-anti-mark)) |
1454 | ;; output is from original text | |
1455 | (make-syntax-object | |
1456 | (syntax-object-expression x) | |
30398e94 | 1457 | (make-wrap (cdr ms) (if rib (cons rib (cdr ss)) (cdr ss))) |
8fad25c2 AW |
1458 | (syntax-object-module x)) |
1459 | ;; output introduced by macro | |
1460 | (make-syntax-object | |
1461 | (decorate-source (syntax-object-expression x) s) | |
1462 | (make-wrap (cons m ms) | |
1463 | (if rib | |
30398e94 MW |
1464 | (cons rib (cons 'shift ss)) |
1465 | (cons 'shift ss))) | |
8fad25c2 AW |
1466 | (syntax-object-module x)))))) |
1467 | ||
1468 | ((vector? x) | |
1469 | (let* ((n (vector-length x)) | |
30398e94 | 1470 | (v (decorate-source (make-vector n) s))) |
8fad25c2 AW |
1471 | (do ((i 0 (fx+ i 1))) |
1472 | ((fx= i n) v) | |
1473 | (vector-set! v i | |
1474 | (rebuild-macro-output (vector-ref x i) m))))) | |
1475 | ((symbol? x) | |
1476 | (syntax-violation #f "encountered raw symbol in macro output" | |
1477 | (source-wrap e w (wrap-subst w) mod) x)) | |
1478 | (else (decorate-source x s))))) | |
9b0975f1 AW |
1479 | (with-fluids ((transformer-environment |
1480 | (lambda (k) (k e r w s rib mod)))) | |
1481 | (rebuild-macro-output (p (source-wrap e (anti-mark w) s mod)) | |
1482 | (new-mark))))) | |
8fad25c2 | 1483 | |
78a47455 | 1484 | (define expand-body |
8fad25c2 AW |
1485 | ;; In processing the forms of the body, we create a new, empty wrap. |
1486 | ;; This wrap is augmented (destructively) each time we discover that | |
1487 | ;; the next form is a definition. This is done: | |
1488 | ;; | |
1489 | ;; (1) to allow the first nondefinition form to be a call to | |
1490 | ;; one of the defined ids even if the id previously denoted a | |
1491 | ;; definition keyword or keyword for a macro expanding into a | |
1492 | ;; definition; | |
1493 | ;; (2) to prevent subsequent definition forms (but unfortunately | |
1494 | ;; not earlier ones) and the first nondefinition form from | |
1495 | ;; confusing one of the bound identifiers for an auxiliary | |
1496 | ;; keyword; and | |
1497 | ;; (3) so that we do not need to restart the expansion of the | |
1498 | ;; first nondefinition form, which is problematic anyway | |
1499 | ;; since it might be the first element of a begin that we | |
1500 | ;; have just spliced into the body (meaning if we restarted, | |
1501 | ;; we'd really need to restart with the begin or the macro | |
1502 | ;; call that expanded into the begin, and we'd have to give | |
1503 | ;; up allowing (begin <defn>+ <expr>+), which is itself | |
1504 | ;; problematic since we don't know if a begin contains only | |
1505 | ;; definitions until we've expanded it). | |
1506 | ;; | |
1507 | ;; Before processing the body, we also create a new environment | |
1508 | ;; containing a placeholder for the bindings we will add later and | |
1509 | ;; associate this environment with each form. In processing a | |
1510 | ;; let-syntax or letrec-syntax, the associated environment may be | |
1511 | ;; augmented with local keyword bindings, so the environment may | |
1512 | ;; be different for different forms in the body. Once we have | |
1513 | ;; gathered up all of the definitions, we evaluate the transformer | |
1514 | ;; expressions and splice into r at the placeholder the new variable | |
1515 | ;; and keyword bindings. This allows let-syntax or letrec-syntax | |
1516 | ;; forms local to a portion or all of the body to shadow the | |
1517 | ;; definition bindings. | |
1518 | ;; | |
1519 | ;; Subforms of a begin, let-syntax, or letrec-syntax are spliced | |
1520 | ;; into the body. | |
1521 | ;; | |
1522 | ;; outer-form is fully wrapped w/source | |
1523 | (lambda (body outer-form r w mod) | |
1524 | (let* ((r (cons '("placeholder" . (placeholder)) r)) | |
1525 | (ribcage (make-empty-ribcage)) | |
1526 | (w (make-wrap (wrap-marks w) (cons ribcage (wrap-subst w))))) | |
1527 | (let parse ((body (map (lambda (x) (cons r (wrap x w mod))) body)) | |
1528 | (ids '()) (labels '()) | |
1529 | (var-ids '()) (vars '()) (vals '()) (bindings '())) | |
1530 | (if (null? body) | |
1531 | (syntax-violation #f "no expressions in body" outer-form) | |
1532 | (let ((e (cdar body)) (er (caar body))) | |
1533 | (call-with-values | |
1534 | (lambda () (syntax-type e er empty-wrap (source-annotation er) ribcage mod #f)) | |
40e92f09 | 1535 | (lambda (type value form e w s mod) |
8fad25c2 AW |
1536 | (case type |
1537 | ((define-form) | |
1538 | (let ((id (wrap value w mod)) (label (gen-label))) | |
1539 | (let ((var (gen-var id))) | |
1540 | (extend-ribcage! ribcage id label) | |
1541 | (parse (cdr body) | |
1542 | (cons id ids) (cons label labels) | |
1543 | (cons id var-ids) | |
1544 | (cons var vars) (cons (cons er (wrap e w mod)) vals) | |
1545 | (cons (make-binding 'lexical var) bindings))))) | |
c2d822de | 1546 | ((define-syntax-form define-syntax-parameter-form) |
8fad25c2 | 1547 | (let ((id (wrap value w mod)) (label (gen-label))) |
c3ae0ed4 AW |
1548 | (extend-ribcage! ribcage id label) |
1549 | (parse (cdr body) | |
1550 | (cons id ids) (cons label labels) | |
8fad25c2 | 1551 | var-ids vars vals |
5b36d603 AW |
1552 | (cons (make-binding |
1553 | (if (eq? type 'define-syntax-parameter-form) | |
1554 | 'syntax-parameter | |
1555 | 'macro) | |
1556 | (cons er (wrap e w mod))) | |
8fad25c2 AW |
1557 | bindings)))) |
1558 | ((begin-form) | |
1559 | (syntax-case e () | |
1560 | ((_ e1 ...) | |
1561 | (parse (let f ((forms #'(e1 ...))) | |
1562 | (if (null? forms) | |
1563 | (cdr body) | |
1564 | (cons (cons er (wrap (car forms) w mod)) | |
1565 | (f (cdr forms))))) | |
1566 | ids labels var-ids vars vals bindings)))) | |
1567 | ((local-syntax-form) | |
78a47455 AW |
1568 | (expand-local-syntax value e er w s mod |
1569 | (lambda (forms er w s mod) | |
1570 | (parse (let f ((forms forms)) | |
1571 | (if (null? forms) | |
1572 | (cdr body) | |
1573 | (cons (cons er (wrap (car forms) w mod)) | |
1574 | (f (cdr forms))))) | |
1575 | ids labels var-ids vars vals bindings)))) | |
8fad25c2 AW |
1576 | (else ; found a non-definition |
1577 | (if (null? ids) | |
1578 | (build-sequence no-source | |
1579 | (map (lambda (x) | |
78a47455 | 1580 | (expand (cdr x) (car x) empty-wrap mod)) |
8fad25c2 AW |
1581 | (cons (cons er (source-wrap e w s mod)) |
1582 | (cdr body)))) | |
1583 | (begin | |
1584 | (if (not (valid-bound-ids? ids)) | |
1585 | (syntax-violation | |
1586 | #f "invalid or duplicate identifier in definition" | |
1587 | outer-form)) | |
1588 | (let loop ((bs bindings) (er-cache #f) (r-cache #f)) | |
1589 | (if (not (null? bs)) | |
1590 | (let* ((b (car bs))) | |
5b36d603 | 1591 | (if (memq (car b) '(macro syntax-parameter)) |
8fad25c2 AW |
1592 | (let* ((er (cadr b)) |
1593 | (r-cache | |
1594 | (if (eq? er er-cache) | |
1595 | r-cache | |
1596 | (macros-only-env er)))) | |
1597 | (set-cdr! b | |
1598 | (eval-local-transformer | |
78a47455 | 1599 | (expand (cddr b) r-cache empty-wrap mod) |
8fad25c2 | 1600 | mod)) |
5b36d603 AW |
1601 | (if (eq? (car b) 'syntax-parameter) |
1602 | (set-cdr! b (list (cdr b)))) | |
8fad25c2 AW |
1603 | (loop (cdr bs) er r-cache)) |
1604 | (loop (cdr bs) er-cache r-cache))))) | |
1605 | (set-cdr! r (extend-env labels bindings (cdr r))) | |
1606 | (build-letrec no-source #t | |
1607 | (reverse (map syntax->datum var-ids)) | |
1608 | (reverse vars) | |
1609 | (map (lambda (x) | |
78a47455 | 1610 | (expand (cdr x) (car x) empty-wrap mod)) |
8fad25c2 AW |
1611 | (reverse vals)) |
1612 | (build-sequence no-source | |
1613 | (map (lambda (x) | |
78a47455 | 1614 | (expand (cdr x) (car x) empty-wrap mod)) |
8fad25c2 AW |
1615 | (cons (cons er (source-wrap e w s mod)) |
1616 | (cdr body))))))))))))))))) | |
1617 | ||
78a47455 | 1618 | (define expand-local-syntax |
8fad25c2 AW |
1619 | (lambda (rec? e r w s mod k) |
1620 | (syntax-case e () | |
1621 | ((_ ((id val) ...) e1 e2 ...) | |
1622 | (let ((ids #'(id ...))) | |
1623 | (if (not (valid-bound-ids? ids)) | |
1624 | (syntax-violation #f "duplicate bound keyword" e) | |
1625 | (let ((labels (gen-labels ids))) | |
1626 | (let ((new-w (make-binding-wrap ids labels w))) | |
1627 | (k #'(e1 e2 ...) | |
1628 | (extend-env | |
1629 | labels | |
1630 | (let ((w (if rec? new-w w)) | |
1631 | (trans-r (macros-only-env r))) | |
1632 | (map (lambda (x) | |
1633 | (make-binding 'macro | |
1634 | (eval-local-transformer | |
78a47455 | 1635 | (expand x trans-r w mod) |
8fad25c2 AW |
1636 | mod))) |
1637 | #'(val ...))) | |
1638 | r) | |
1639 | new-w | |
1640 | s | |
1641 | mod)))))) | |
1642 | (_ (syntax-violation #f "bad local syntax definition" | |
1643 | (source-wrap e w s mod)))))) | |
1644 | ||
1645 | (define eval-local-transformer | |
1646 | (lambda (expanded mod) | |
1647 | (let ((p (local-eval-hook expanded mod))) | |
1648 | (if (procedure? p) | |
1649 | p | |
1650 | (syntax-violation #f "nonprocedure transformer" p))))) | |
1651 | ||
78a47455 | 1652 | (define expand-void |
8fad25c2 AW |
1653 | (lambda () |
1654 | (build-void no-source))) | |
1655 | ||
1656 | (define ellipsis? | |
1657 | (lambda (x) | |
1658 | (and (nonsymbol-id? x) | |
1659 | (free-id=? x #'(... ...))))) | |
1660 | ||
1661 | (define lambda-formals | |
1662 | (lambda (orig-args) | |
1663 | (define (req args rreq) | |
1664 | (syntax-case args () | |
1665 | (() | |
1666 | (check (reverse rreq) #f)) | |
1667 | ((a . b) (id? #'a) | |
1668 | (req #'b (cons #'a rreq))) | |
1669 | (r (id? #'r) | |
1670 | (check (reverse rreq) #'r)) | |
1671 | (else | |
1672 | (syntax-violation 'lambda "invalid argument list" orig-args args)))) | |
1673 | (define (check req rest) | |
1674 | (cond | |
1675 | ((distinct-bound-ids? (if rest (cons rest req) req)) | |
1676 | (values req #f rest #f)) | |
1677 | (else | |
1678 | (syntax-violation 'lambda "duplicate identifier in argument list" | |
1679 | orig-args)))) | |
1680 | (req orig-args '()))) | |
1681 | ||
78a47455 | 1682 | (define expand-simple-lambda |
8fad25c2 AW |
1683 | (lambda (e r w s mod req rest meta body) |
1684 | (let* ((ids (if rest (append req (list rest)) req)) | |
1685 | (vars (map gen-var ids)) | |
1686 | (labels (gen-labels ids))) | |
1687 | (build-simple-lambda | |
1688 | s | |
1689 | (map syntax->datum req) (and rest (syntax->datum rest)) vars | |
1690 | meta | |
78a47455 AW |
1691 | (expand-body body (source-wrap e w s mod) |
1692 | (extend-var-env labels vars r) | |
1693 | (make-binding-wrap ids labels w) | |
1694 | mod))))) | |
8fad25c2 AW |
1695 | |
1696 | (define lambda*-formals | |
1697 | (lambda (orig-args) | |
1698 | (define (req args rreq) | |
1699 | (syntax-case args () | |
1700 | (() | |
1701 | (check (reverse rreq) '() #f '())) | |
1702 | ((a . b) (id? #'a) | |
1703 | (req #'b (cons #'a rreq))) | |
1704 | ((a . b) (eq? (syntax->datum #'a) #:optional) | |
1705 | (opt #'b (reverse rreq) '())) | |
1706 | ((a . b) (eq? (syntax->datum #'a) #:key) | |
1707 | (key #'b (reverse rreq) '() '())) | |
1708 | ((a b) (eq? (syntax->datum #'a) #:rest) | |
1709 | (rest #'b (reverse rreq) '() '())) | |
1710 | (r (id? #'r) | |
1711 | (rest #'r (reverse rreq) '() '())) | |
1712 | (else | |
1713 | (syntax-violation 'lambda* "invalid argument list" orig-args args)))) | |
1714 | (define (opt args req ropt) | |
1715 | (syntax-case args () | |
1716 | (() | |
1717 | (check req (reverse ropt) #f '())) | |
1718 | ((a . b) (id? #'a) | |
1719 | (opt #'b req (cons #'(a #f) ropt))) | |
1720 | (((a init) . b) (id? #'a) | |
1721 | (opt #'b req (cons #'(a init) ropt))) | |
1722 | ((a . b) (eq? (syntax->datum #'a) #:key) | |
1723 | (key #'b req (reverse ropt) '())) | |
1724 | ((a b) (eq? (syntax->datum #'a) #:rest) | |
1725 | (rest #'b req (reverse ropt) '())) | |
1726 | (r (id? #'r) | |
1727 | (rest #'r req (reverse ropt) '())) | |
1728 | (else | |
1729 | (syntax-violation 'lambda* "invalid optional argument list" | |
1730 | orig-args args)))) | |
1731 | (define (key args req opt rkey) | |
1732 | (syntax-case args () | |
1733 | (() | |
1734 | (check req opt #f (cons #f (reverse rkey)))) | |
1735 | ((a . b) (id? #'a) | |
1736 | (with-syntax ((k (symbol->keyword (syntax->datum #'a)))) | |
1737 | (key #'b req opt (cons #'(k a #f) rkey)))) | |
1738 | (((a init) . b) (id? #'a) | |
1739 | (with-syntax ((k (symbol->keyword (syntax->datum #'a)))) | |
1740 | (key #'b req opt (cons #'(k a init) rkey)))) | |
1741 | (((a init k) . b) (and (id? #'a) | |
1742 | (keyword? (syntax->datum #'k))) | |
1743 | (key #'b req opt (cons #'(k a init) rkey))) | |
1744 | ((aok) (eq? (syntax->datum #'aok) #:allow-other-keys) | |
1745 | (check req opt #f (cons #t (reverse rkey)))) | |
1746 | ((aok a b) (and (eq? (syntax->datum #'aok) #:allow-other-keys) | |
1747 | (eq? (syntax->datum #'a) #:rest)) | |
1748 | (rest #'b req opt (cons #t (reverse rkey)))) | |
1749 | ((aok . r) (and (eq? (syntax->datum #'aok) #:allow-other-keys) | |
1750 | (id? #'r)) | |
1751 | (rest #'r req opt (cons #t (reverse rkey)))) | |
1752 | ((a b) (eq? (syntax->datum #'a) #:rest) | |
1753 | (rest #'b req opt (cons #f (reverse rkey)))) | |
1754 | (r (id? #'r) | |
1755 | (rest #'r req opt (cons #f (reverse rkey)))) | |
1756 | (else | |
1757 | (syntax-violation 'lambda* "invalid keyword argument list" | |
1758 | orig-args args)))) | |
1759 | (define (rest args req opt kw) | |
1760 | (syntax-case args () | |
1761 | (r (id? #'r) | |
1762 | (check req opt #'r kw)) | |
1763 | (else | |
1764 | (syntax-violation 'lambda* "invalid rest argument" | |
1765 | orig-args args)))) | |
1766 | (define (check req opt rest kw) | |
1767 | (cond | |
1768 | ((distinct-bound-ids? | |
1769 | (append req (map car opt) (if rest (list rest) '()) | |
1770 | (if (pair? kw) (map cadr (cdr kw)) '()))) | |
1771 | (values req opt rest kw)) | |
1772 | (else | |
1773 | (syntax-violation 'lambda* "duplicate identifier in argument list" | |
1774 | orig-args)))) | |
1775 | (req orig-args '()))) | |
1776 | ||
78a47455 | 1777 | (define expand-lambda-case |
8fad25c2 | 1778 | (lambda (e r w s mod get-formals clauses) |
78a47455 | 1779 | (define (parse-req req opt rest kw body) |
8fad25c2 AW |
1780 | (let ((vars (map gen-var req)) |
1781 | (labels (gen-labels req))) | |
1782 | (let ((r* (extend-var-env labels vars r)) | |
1783 | (w* (make-binding-wrap req labels w))) | |
78a47455 AW |
1784 | (parse-opt (map syntax->datum req) |
1785 | opt rest kw body (reverse vars) r* w* '() '())))) | |
1786 | (define (parse-opt req opt rest kw body vars r* w* out inits) | |
8fad25c2 AW |
1787 | (cond |
1788 | ((pair? opt) | |
1789 | (syntax-case (car opt) () | |
1790 | ((id i) | |
1791 | (let* ((v (gen-var #'id)) | |
1792 | (l (gen-labels (list v))) | |
1793 | (r** (extend-var-env l (list v) r*)) | |
1794 | (w** (make-binding-wrap (list #'id) l w*))) | |
78a47455 AW |
1795 | (parse-opt req (cdr opt) rest kw body (cons v vars) |
1796 | r** w** (cons (syntax->datum #'id) out) | |
1797 | (cons (expand #'i r* w* mod) inits)))))) | |
8fad25c2 AW |
1798 | (rest |
1799 | (let* ((v (gen-var rest)) | |
1800 | (l (gen-labels (list v))) | |
1801 | (r* (extend-var-env l (list v) r*)) | |
1802 | (w* (make-binding-wrap (list rest) l w*))) | |
78a47455 AW |
1803 | (parse-kw req (if (pair? out) (reverse out) #f) |
1804 | (syntax->datum rest) | |
1805 | (if (pair? kw) (cdr kw) kw) | |
1806 | body (cons v vars) r* w* | |
1807 | (if (pair? kw) (car kw) #f) | |
1808 | '() inits))) | |
8fad25c2 | 1809 | (else |
78a47455 AW |
1810 | (parse-kw req (if (pair? out) (reverse out) #f) #f |
1811 | (if (pair? kw) (cdr kw) kw) | |
1812 | body vars r* w* | |
1813 | (if (pair? kw) (car kw) #f) | |
1814 | '() inits)))) | |
1815 | (define (parse-kw req opt rest kw body vars r* w* aok out inits) | |
8fad25c2 AW |
1816 | (cond |
1817 | ((pair? kw) | |
1818 | (syntax-case (car kw) () | |
1819 | ((k id i) | |
1820 | (let* ((v (gen-var #'id)) | |
1821 | (l (gen-labels (list v))) | |
1822 | (r** (extend-var-env l (list v) r*)) | |
1823 | (w** (make-binding-wrap (list #'id) l w*))) | |
78a47455 AW |
1824 | (parse-kw req opt rest (cdr kw) body (cons v vars) |
1825 | r** w** aok | |
1826 | (cons (list (syntax->datum #'k) | |
1827 | (syntax->datum #'id) | |
1828 | v) | |
1829 | out) | |
1830 | (cons (expand #'i r* w* mod) inits)))))) | |
8fad25c2 | 1831 | (else |
78a47455 AW |
1832 | (parse-body req opt rest |
1833 | (if (or aok (pair? out)) (cons aok (reverse out)) #f) | |
1834 | body (reverse vars) r* w* (reverse inits) '())))) | |
1835 | (define (parse-body req opt rest kw body vars r* w* inits meta) | |
8fad25c2 AW |
1836 | (syntax-case body () |
1837 | ((docstring e1 e2 ...) (string? (syntax->datum #'docstring)) | |
78a47455 AW |
1838 | (parse-body req opt rest kw #'(e1 e2 ...) vars r* w* inits |
1839 | (append meta | |
1840 | `((documentation | |
1841 | . ,(syntax->datum #'docstring)))))) | |
8fad25c2 | 1842 | ((#((k . v) ...) e1 e2 ...) |
78a47455 AW |
1843 | (parse-body req opt rest kw #'(e1 e2 ...) vars r* w* inits |
1844 | (append meta (syntax->datum #'((k . v) ...))))) | |
8fad25c2 AW |
1845 | ((e1 e2 ...) |
1846 | (values meta req opt rest kw inits vars | |
78a47455 AW |
1847 | (expand-body #'(e1 e2 ...) (source-wrap e w s mod) |
1848 | r* w* mod))))) | |
8fad25c2 AW |
1849 | |
1850 | (syntax-case clauses () | |
1851 | (() (values '() #f)) | |
1852 | (((args e1 e2 ...) (args* e1* e2* ...) ...) | |
1853 | (call-with-values (lambda () (get-formals #'args)) | |
1854 | (lambda (req opt rest kw) | |
1855 | (call-with-values (lambda () | |
78a47455 | 1856 | (parse-req req opt rest kw #'(e1 e2 ...))) |
8fad25c2 AW |
1857 | (lambda (meta req opt rest kw inits vars body) |
1858 | (call-with-values | |
1859 | (lambda () | |
78a47455 AW |
1860 | (expand-lambda-case e r w s mod get-formals |
1861 | #'((args* e1* e2* ...) ...))) | |
8fad25c2 AW |
1862 | (lambda (meta* else*) |
1863 | (values | |
1864 | (append meta meta*) | |
1865 | (build-lambda-case s req opt rest kw inits vars | |
1866 | body else*)))))))))))) | |
1867 | ||
1868 | ;; data | |
1869 | ||
1870 | ;; strips syntax-objects down to top-wrap | |
1871 | ;; | |
1872 | ;; since only the head of a list is annotated by the reader, not each pair | |
1873 | ;; in the spine, we also check for pairs whose cars are annotated in case | |
1874 | ;; we've been passed the cdr of an annotated list | |
1875 | ||
1876 | (define strip | |
1877 | (lambda (x w) | |
1878 | (if (top-marked? w) | |
1879 | x | |
1880 | (let f ((x x)) | |
1881 | (cond | |
1882 | ((syntax-object? x) | |
1883 | (strip (syntax-object-expression x) (syntax-object-wrap x))) | |
1884 | ((pair? x) | |
1885 | (let ((a (f (car x))) (d (f (cdr x)))) | |
1886 | (if (and (eq? a (car x)) (eq? d (cdr x))) | |
1887 | x | |
1888 | (cons a d)))) | |
1889 | ((vector? x) | |
1890 | (let ((old (vector->list x))) | |
1891 | (let ((new (map f old))) | |
e2ccab57 AW |
1892 | ;; inlined and-map with two args |
1893 | (let lp ((l1 old) (l2 new)) | |
1894 | (if (null? l1) | |
1895 | x | |
1896 | (if (eq? (car l1) (car l2)) | |
1897 | (lp (cdr l1) (cdr l2)) | |
1898 | (list->vector new))))))) | |
8fad25c2 AW |
1899 | (else x)))))) |
1900 | ||
1901 | ;; lexical variables | |
1902 | ||
1903 | (define gen-var | |
1904 | (lambda (id) | |
1905 | (let ((id (if (syntax-object? id) (syntax-object-expression id) id))) | |
1906 | (build-lexical-var no-source id)))) | |
1907 | ||
1908 | ;; appears to return a reversed list | |
1909 | (define lambda-var-list | |
1910 | (lambda (vars) | |
1911 | (let lvl ((vars vars) (ls '()) (w empty-wrap)) | |
1912 | (cond | |
1913 | ((pair? vars) (lvl (cdr vars) (cons (wrap (car vars) w #f) ls) w)) | |
1914 | ((id? vars) (cons (wrap vars w #f) ls)) | |
1915 | ((null? vars) ls) | |
1916 | ((syntax-object? vars) | |
1917 | (lvl (syntax-object-expression vars) | |
1918 | ls | |
1919 | (join-wraps w (syntax-object-wrap vars)))) | |
1920 | ;; include anything else to be caught by subsequent error | |
1921 | ;; checking | |
1922 | (else (cons vars ls)))))) | |
1923 | ||
1924 | ;; core transformers | |
1925 | ||
1926 | (global-extend 'local-syntax 'letrec-syntax #t) | |
1927 | (global-extend 'local-syntax 'let-syntax #f) | |
1928 | ||
c070de63 | 1929 | (global-extend |
ea3ca4e4 | 1930 | 'core 'syntax-parameterize |
c070de63 AW |
1931 | (lambda (e r w s mod) |
1932 | (syntax-case e () | |
1933 | ((_ ((var val) ...) e1 e2 ...) | |
1934 | (valid-bound-ids? #'(var ...)) | |
1935 | (let ((names | |
1936 | (map (lambda (x) | |
1937 | (call-with-values | |
5b36d603 AW |
1938 | (lambda () (resolve-identifier x w r mod #f)) |
1939 | (lambda (type value mod) | |
c070de63 AW |
1940 | (case type |
1941 | ((displaced-lexical) | |
ea3ca4e4 | 1942 | (syntax-violation 'syntax-parameterize |
c070de63 AW |
1943 | "identifier out of context" |
1944 | e | |
1945 | (source-wrap x w s mod))) | |
5b36d603 AW |
1946 | ((syntax-parameter) |
1947 | value) | |
1948 | (else | |
1949 | (syntax-violation 'syntax-parameterize | |
1950 | "invalid syntax parameter" | |
1951 | e | |
1952 | (source-wrap x w s mod))))))) | |
c070de63 AW |
1953 | #'(var ...))) |
1954 | (bindings | |
1955 | (let ((trans-r (macros-only-env r))) | |
1956 | (map (lambda (x) | |
1957 | (make-binding | |
1958 | 'macro | |
b2208d2e | 1959 | (eval-local-transformer (expand x trans-r w mod) mod))) |
c070de63 | 1960 | #'(val ...))))) |
b2208d2e | 1961 | (expand-body #'(e1 e2 ...) |
c070de63 AW |
1962 | (source-wrap e w s mod) |
1963 | (extend-env names bindings r) | |
1964 | w | |
1965 | mod))) | |
ea3ca4e4 | 1966 | (_ (syntax-violation 'syntax-parameterize "bad syntax" |
c070de63 | 1967 | (source-wrap e w s mod)))))) |
8fad25c2 AW |
1968 | |
1969 | (global-extend 'core 'quote | |
1970 | (lambda (e r w s mod) | |
1971 | (syntax-case e () | |
1972 | ((_ e) (build-data s (strip #'e w))) | |
1973 | (_ (syntax-violation 'quote "bad syntax" | |
1974 | (source-wrap e w s mod)))))) | |
1975 | ||
c070de63 AW |
1976 | (global-extend |
1977 | 'core 'syntax | |
1978 | (let () | |
1979 | (define gen-syntax | |
1980 | (lambda (src e r maps ellipsis? mod) | |
1981 | (if (id? e) | |
1982 | (call-with-values (lambda () | |
5b36d603 AW |
1983 | (resolve-identifier e empty-wrap r mod #f)) |
1984 | (lambda (type value mod) | |
c070de63 AW |
1985 | (case type |
1986 | ((syntax) | |
1987 | (call-with-values | |
1988 | (lambda () (gen-ref src (car value) (cdr value) maps)) | |
1989 | (lambda (var maps) | |
1990 | (values `(ref ,var) maps)))) | |
1991 | (else | |
1992 | (if (ellipsis? e) | |
1993 | (syntax-violation 'syntax "misplaced ellipsis" src) | |
1994 | (values `(quote ,e) maps)))))) | |
1995 | (syntax-case e () | |
1996 | ((dots e) | |
1997 | (ellipsis? #'dots) | |
1998 | (gen-syntax src #'e r maps (lambda (x) #f) mod)) | |
1999 | ((x dots . y) | |
2000 | ;; this could be about a dozen lines of code, except that we | |
2001 | ;; choose to handle #'(x ... ...) forms | |
2002 | (ellipsis? #'dots) | |
2003 | (let f ((y #'y) | |
2004 | (k (lambda (maps) | |
2005 | (call-with-values | |
2006 | (lambda () | |
2007 | (gen-syntax src #'x r | |
2008 | (cons '() maps) ellipsis? mod)) | |
2009 | (lambda (x maps) | |
2010 | (if (null? (car maps)) | |
2011 | (syntax-violation 'syntax "extra ellipsis" | |
2012 | src) | |
2013 | (values (gen-map x (car maps)) | |
2014 | (cdr maps)))))))) | |
2015 | (syntax-case y () | |
2016 | ((dots . y) | |
2017 | (ellipsis? #'dots) | |
2018 | (f #'y | |
2019 | (lambda (maps) | |
8fad25c2 | 2020 | (call-with-values |
c070de63 AW |
2021 | (lambda () (k (cons '() maps))) |
2022 | (lambda (x maps) | |
2023 | (if (null? (car maps)) | |
2024 | (syntax-violation 'syntax "extra ellipsis" src) | |
2025 | (values (gen-mappend x (car maps)) | |
2026 | (cdr maps)))))))) | |
2027 | (_ (call-with-values | |
2028 | (lambda () (gen-syntax src y r maps ellipsis? mod)) | |
2029 | (lambda (y maps) | |
2030 | (call-with-values | |
2031 | (lambda () (k maps)) | |
2032 | (lambda (x maps) | |
2033 | (values (gen-append x y) maps))))))))) | |
2034 | ((x . y) | |
2035 | (call-with-values | |
2036 | (lambda () (gen-syntax src #'x r maps ellipsis? mod)) | |
2037 | (lambda (x maps) | |
2038 | (call-with-values | |
2039 | (lambda () (gen-syntax src #'y r maps ellipsis? mod)) | |
2040 | (lambda (y maps) (values (gen-cons x y) maps)))))) | |
2041 | (#(e1 e2 ...) | |
2042 | (call-with-values | |
2043 | (lambda () | |
2044 | (gen-syntax src #'(e1 e2 ...) r maps ellipsis? mod)) | |
2045 | (lambda (e maps) (values (gen-vector e) maps)))) | |
2046 | (_ (values `(quote ,e) maps)))))) | |
2047 | ||
2048 | (define gen-ref | |
2049 | (lambda (src var level maps) | |
2050 | (if (fx= level 0) | |
2051 | (values var maps) | |
2052 | (if (null? maps) | |
2053 | (syntax-violation 'syntax "missing ellipsis" src) | |
2054 | (call-with-values | |
2055 | (lambda () (gen-ref src var (fx- level 1) (cdr maps))) | |
2056 | (lambda (outer-var outer-maps) | |
2057 | (let ((b (assq outer-var (car maps)))) | |
2058 | (if b | |
2059 | (values (cdr b) maps) | |
2060 | (let ((inner-var (gen-var 'tmp))) | |
2061 | (values inner-var | |
2062 | (cons (cons (cons outer-var inner-var) | |
2063 | (car maps)) | |
2064 | outer-maps))))))))))) | |
2065 | ||
2066 | (define gen-mappend | |
2067 | (lambda (e map-env) | |
2068 | `(apply (primitive append) ,(gen-map e map-env)))) | |
2069 | ||
2070 | (define gen-map | |
2071 | (lambda (e map-env) | |
2072 | (let ((formals (map cdr map-env)) | |
2073 | (actuals (map (lambda (x) `(ref ,(car x))) map-env))) | |
2074 | (cond | |
2075 | ((eq? (car e) 'ref) | |
2076 | ;; identity map equivalence: | |
2077 | ;; (map (lambda (x) x) y) == y | |
2078 | (car actuals)) | |
2079 | ((and-map | |
2080 | (lambda (x) (and (eq? (car x) 'ref) (memq (cadr x) formals))) | |
2081 | (cdr e)) | |
2082 | ;; eta map equivalence: | |
2083 | ;; (map (lambda (x ...) (f x ...)) y ...) == (map f y ...) | |
2084 | `(map (primitive ,(car e)) | |
2085 | ,@(map (let ((r (map cons formals actuals))) | |
2086 | (lambda (x) (cdr (assq (cadr x) r)))) | |
2087 | (cdr e)))) | |
2088 | (else `(map (lambda ,formals ,e) ,@actuals)))))) | |
2089 | ||
2090 | (define gen-cons | |
2091 | (lambda (x y) | |
2092 | (case (car y) | |
2093 | ((quote) | |
2094 | (if (eq? (car x) 'quote) | |
2095 | `(quote (,(cadr x) . ,(cadr y))) | |
2096 | (if (eq? (cadr y) '()) | |
2097 | `(list ,x) | |
2098 | `(cons ,x ,y)))) | |
2099 | ((list) `(list ,x ,@(cdr y))) | |
2100 | (else `(cons ,x ,y))))) | |
2101 | ||
2102 | (define gen-append | |
2103 | (lambda (x y) | |
2104 | (if (equal? y '(quote ())) | |
2105 | x | |
2106 | `(append ,x ,y)))) | |
2107 | ||
2108 | (define gen-vector | |
2109 | (lambda (x) | |
2110 | (cond | |
2111 | ((eq? (car x) 'list) `(vector ,@(cdr x))) | |
2112 | ((eq? (car x) 'quote) `(quote #(,@(cadr x)))) | |
2113 | (else `(list->vector ,x))))) | |
2114 | ||
2115 | ||
2116 | (define regen | |
2117 | (lambda (x) | |
2118 | (case (car x) | |
2119 | ((ref) (build-lexical-reference 'value no-source (cadr x) (cadr x))) | |
2120 | ((primitive) (build-primref no-source (cadr x))) | |
2121 | ((quote) (build-data no-source (cadr x))) | |
2122 | ((lambda) | |
2123 | (if (list? (cadr x)) | |
2124 | (build-simple-lambda no-source (cadr x) #f (cadr x) '() (regen (caddr x))) | |
2125 | (error "how did we get here" x))) | |
2126 | (else (build-primcall no-source (car x) (map regen (cdr x))))))) | |
2127 | ||
2128 | (lambda (e r w s mod) | |
2129 | (let ((e (source-wrap e w s mod))) | |
2130 | (syntax-case e () | |
2131 | ((_ x) | |
2132 | (call-with-values | |
2133 | (lambda () (gen-syntax e #'x r '() ellipsis? mod)) | |
2134 | (lambda (e maps) (regen e)))) | |
2135 | (_ (syntax-violation 'syntax "bad `syntax' form" e))))))) | |
8fad25c2 AW |
2136 | |
2137 | (global-extend 'core 'lambda | |
c3ae0ed4 | 2138 | (lambda (e r w s mod) |
8fad25c2 AW |
2139 | (syntax-case e () |
2140 | ((_ args e1 e2 ...) | |
2141 | (call-with-values (lambda () (lambda-formals #'args)) | |
2142 | (lambda (req opt rest kw) | |
2143 | (let lp ((body #'(e1 e2 ...)) (meta '())) | |
2144 | (syntax-case body () | |
2145 | ((docstring e1 e2 ...) (string? (syntax->datum #'docstring)) | |
2146 | (lp #'(e1 e2 ...) | |
2147 | (append meta | |
2148 | `((documentation | |
2149 | . ,(syntax->datum #'docstring)))))) | |
2150 | ((#((k . v) ...) e1 e2 ...) | |
2151 | (lp #'(e1 e2 ...) | |
2152 | (append meta (syntax->datum #'((k . v) ...))))) | |
78a47455 | 2153 | (_ (expand-simple-lambda e r w s mod req rest meta body))))))) |
8fad25c2 | 2154 | (_ (syntax-violation 'lambda "bad lambda" e))))) |
3785c5b2 | 2155 | |
8fad25c2 AW |
2156 | (global-extend 'core 'lambda* |
2157 | (lambda (e r w s mod) | |
2158 | (syntax-case e () | |
2159 | ((_ args e1 e2 ...) | |
2160 | (call-with-values | |
2161 | (lambda () | |
78a47455 AW |
2162 | (expand-lambda-case e r w s mod |
2163 | lambda*-formals #'((args e1 e2 ...)))) | |
8fad25c2 AW |
2164 | (lambda (meta lcase) |
2165 | (build-case-lambda s meta lcase)))) | |
2166 | (_ (syntax-violation 'lambda "bad lambda*" e))))) | |
2167 | ||
2168 | (global-extend 'core 'case-lambda | |
2169 | (lambda (e r w s mod) | |
2170 | (syntax-case e () | |
2171 | ((_ (args e1 e2 ...) (args* e1* e2* ...) ...) | |
2172 | (call-with-values | |
2173 | (lambda () | |
78a47455 AW |
2174 | (expand-lambda-case e r w s mod |
2175 | lambda-formals | |
2176 | #'((args e1 e2 ...) (args* e1* e2* ...) ...))) | |
8fad25c2 AW |
2177 | (lambda (meta lcase) |
2178 | (build-case-lambda s meta lcase)))) | |
2179 | (_ (syntax-violation 'case-lambda "bad case-lambda" e))))) | |
2180 | ||
2181 | (global-extend 'core 'case-lambda* | |
2182 | (lambda (e r w s mod) | |
2183 | (syntax-case e () | |
2184 | ((_ (args e1 e2 ...) (args* e1* e2* ...) ...) | |
2185 | (call-with-values | |
2186 | (lambda () | |
78a47455 AW |
2187 | (expand-lambda-case e r w s mod |
2188 | lambda*-formals | |
2189 | #'((args e1 e2 ...) (args* e1* e2* ...) ...))) | |
8fad25c2 AW |
2190 | (lambda (meta lcase) |
2191 | (build-case-lambda s meta lcase)))) | |
2192 | (_ (syntax-violation 'case-lambda "bad case-lambda*" e))))) | |
2193 | ||
2194 | (global-extend 'core 'let | |
2195 | (let () | |
78a47455 | 2196 | (define (expand-let e r w s mod constructor ids vals exps) |
8fad25c2 AW |
2197 | (if (not (valid-bound-ids? ids)) |
2198 | (syntax-violation 'let "duplicate bound variable" e) | |
2199 | (let ((labels (gen-labels ids)) | |
2200 | (new-vars (map gen-var ids))) | |
2201 | (let ((nw (make-binding-wrap ids labels w)) | |
2202 | (nr (extend-var-env labels new-vars r))) | |
2203 | (constructor s | |
2204 | (map syntax->datum ids) | |
2205 | new-vars | |
78a47455 AW |
2206 | (map (lambda (x) (expand x r w mod)) vals) |
2207 | (expand-body exps (source-wrap e nw s mod) | |
2208 | nr nw mod)))))) | |
8fad25c2 AW |
2209 | (lambda (e r w s mod) |
2210 | (syntax-case e () | |
2211 | ((_ ((id val) ...) e1 e2 ...) | |
2212 | (and-map id? #'(id ...)) | |
78a47455 AW |
2213 | (expand-let e r w s mod |
2214 | build-let | |
2215 | #'(id ...) | |
2216 | #'(val ...) | |
2217 | #'(e1 e2 ...))) | |
8fad25c2 AW |
2218 | ((_ f ((id val) ...) e1 e2 ...) |
2219 | (and (id? #'f) (and-map id? #'(id ...))) | |
78a47455 AW |
2220 | (expand-let e r w s mod |
2221 | build-named-let | |
2222 | #'(f id ...) | |
2223 | #'(val ...) | |
2224 | #'(e1 e2 ...))) | |
8fad25c2 AW |
2225 | (_ (syntax-violation 'let "bad let" (source-wrap e w s mod))))))) |
2226 | ||
2227 | ||
2228 | (global-extend 'core 'letrec | |
c3ae0ed4 AW |
2229 | (lambda (e r w s mod) |
2230 | (syntax-case e () | |
2231 | ((_ ((id val) ...) e1 e2 ...) | |
2232 | (and-map id? #'(id ...)) | |
8fad25c2 AW |
2233 | (let ((ids #'(id ...))) |
2234 | (if (not (valid-bound-ids? ids)) | |
2235 | (syntax-violation 'letrec "duplicate bound variable" e) | |
2236 | (let ((labels (gen-labels ids)) | |
2237 | (new-vars (map gen-var ids))) | |
2238 | (let ((w (make-binding-wrap ids labels w)) | |
2239 | (r (extend-var-env labels new-vars r))) | |
2240 | (build-letrec s #f | |
2241 | (map syntax->datum ids) | |
2242 | new-vars | |
78a47455 AW |
2243 | (map (lambda (x) (expand x r w mod)) #'(val ...)) |
2244 | (expand-body #'(e1 e2 ...) | |
2245 | (source-wrap e w s mod) r w mod))))))) | |
8fad25c2 AW |
2246 | (_ (syntax-violation 'letrec "bad letrec" (source-wrap e w s mod)))))) |
2247 | ||
2248 | ||
2249 | (global-extend 'core 'letrec* | |
2250 | (lambda (e r w s mod) | |
2251 | (syntax-case e () | |
2252 | ((_ ((id val) ...) e1 e2 ...) | |
2253 | (and-map id? #'(id ...)) | |
2254 | (let ((ids #'(id ...))) | |
2255 | (if (not (valid-bound-ids? ids)) | |
2256 | (syntax-violation 'letrec* "duplicate bound variable" e) | |
2257 | (let ((labels (gen-labels ids)) | |
2258 | (new-vars (map gen-var ids))) | |
2259 | (let ((w (make-binding-wrap ids labels w)) | |
2260 | (r (extend-var-env labels new-vars r))) | |
2261 | (build-letrec s #t | |
2262 | (map syntax->datum ids) | |
2263 | new-vars | |
78a47455 AW |
2264 | (map (lambda (x) (expand x r w mod)) #'(val ...)) |
2265 | (expand-body #'(e1 e2 ...) | |
2266 | (source-wrap e w s mod) r w mod))))))) | |
8fad25c2 AW |
2267 | (_ (syntax-violation 'letrec* "bad letrec*" (source-wrap e w s mod)))))) |
2268 | ||
2269 | ||
c070de63 AW |
2270 | (global-extend |
2271 | 'core 'set! | |
2272 | (lambda (e r w s mod) | |
2273 | (syntax-case e () | |
2274 | ((_ id val) | |
2275 | (id? #'id) | |
2276 | (call-with-values | |
5b36d603 AW |
2277 | (lambda () (resolve-identifier #'id w r mod #t)) |
2278 | (lambda (type value id-mod) | |
c070de63 AW |
2279 | (case type |
2280 | ((lexical) | |
2281 | (build-lexical-assignment s (syntax->datum #'id) value | |
b2208d2e | 2282 | (expand #'val r w mod))) |
c070de63 | 2283 | ((global) |
b2208d2e | 2284 | (build-global-assignment s value (expand #'val r w mod) id-mod)) |
c070de63 AW |
2285 | ((macro) |
2286 | (if (procedure-property value 'variable-transformer) | |
b2208d2e | 2287 | ;; As syntax-type does, call expand-macro with |
c070de63 | 2288 | ;; the mod of the expression. Hmm. |
b2208d2e | 2289 | (expand (expand-macro value e r w s #f mod) r empty-wrap mod) |
c070de63 AW |
2290 | (syntax-violation 'set! "not a variable transformer" |
2291 | (wrap e w mod) | |
2292 | (wrap #'id w id-mod)))) | |
2293 | ((displaced-lexical) | |
2294 | (syntax-violation 'set! "identifier out of context" | |
2295 | (wrap #'id w mod))) | |
2296 | (else | |
2297 | (syntax-violation 'set! "bad set!" (source-wrap e w s mod))))))) | |
2298 | ((_ (head tail ...) val) | |
2299 | (call-with-values | |
2300 | (lambda () (syntax-type #'head r empty-wrap no-source #f mod #t)) | |
dfadcf85 | 2301 | (lambda (type value ee* ee ww ss modmod) |
c070de63 AW |
2302 | (case type |
2303 | ((module-ref) | |
b2208d2e | 2304 | (let ((val (expand #'val r w mod))) |
c070de63 AW |
2305 | (call-with-values (lambda () (value #'(head tail ...) r w)) |
2306 | (lambda (e r w s* mod) | |
2307 | (syntax-case e () | |
2308 | (e (id? #'e) | |
2309 | (build-global-assignment s (syntax->datum #'e) | |
2310 | val mod))))))) | |
2311 | (else | |
2312 | (build-call s | |
b2208d2e AW |
2313 | (expand #'(setter head) r w mod) |
2314 | (map (lambda (e) (expand e r w mod)) | |
c070de63 AW |
2315 | #'(tail ... val)))))))) |
2316 | (_ (syntax-violation 'set! "bad set!" (source-wrap e w s mod)))))) | |
8fad25c2 AW |
2317 | |
2318 | (global-extend 'module-ref '@ | |
2319 | (lambda (e r w) | |
2320 | (syntax-case e () | |
2321 | ((_ (mod ...) id) | |
2322 | (and (and-map id? #'(mod ...)) (id? #'id)) | |
8210c853 MW |
2323 | ;; Strip the wrap from the identifier and return top-wrap |
2324 | ;; so that the identifier will not be captured by lexicals. | |
2325 | (values (syntax->datum #'id) r top-wrap #f | |
8fad25c2 AW |
2326 | (syntax->datum |
2327 | #'(public mod ...))))))) | |
2328 | ||
2329 | (global-extend 'module-ref '@@ | |
2330 | (lambda (e r w) | |
2331 | (define remodulate | |
2332 | (lambda (x mod) | |
2333 | (cond ((pair? x) | |
2334 | (cons (remodulate (car x) mod) | |
2335 | (remodulate (cdr x) mod))) | |
2336 | ((syntax-object? x) | |
2337 | (make-syntax-object | |
2338 | (remodulate (syntax-object-expression x) mod) | |
2339 | (syntax-object-wrap x) | |
2340 | ;; hither the remodulation | |
2341 | mod)) | |
2342 | ((vector? x) | |
2343 | (let* ((n (vector-length x)) (v (make-vector n))) | |
2344 | (do ((i 0 (fx+ i 1))) | |
2345 | ((fx= i n) v) | |
2346 | (vector-set! v i (remodulate (vector-ref x i) mod))))) | |
2347 | (else x)))) | |
8210c853 MW |
2348 | (syntax-case e (@@) |
2349 | ((_ (mod ...) id) | |
2350 | (and (and-map id? #'(mod ...)) (id? #'id)) | |
2351 | ;; Strip the wrap from the identifier and return top-wrap | |
2352 | ;; so that the identifier will not be captured by lexicals. | |
2353 | (values (syntax->datum #'id) r top-wrap #f | |
2354 | (syntax->datum | |
2355 | #'(private mod ...)))) | |
2356 | ((_ @@ (mod ...) exp) | |
8fad25c2 | 2357 | (and-map id? #'(mod ...)) |
8210c853 MW |
2358 | ;; This is a special syntax used to support R6RS library forms. |
2359 | ;; Unlike the syntax above, the last item is not restricted to | |
2360 | ;; be a single identifier, and the syntax objects are kept | |
2361 | ;; intact, with only their module changed. | |
8fad25c2 AW |
2362 | (let ((mod (syntax->datum #'(private mod ...)))) |
2363 | (values (remodulate #'exp mod) | |
2364 | r w (source-annotation #'exp) | |
2365 | mod)))))) | |
9365d8ad | 2366 | |
8fad25c2 AW |
2367 | (global-extend 'core 'if |
2368 | (lambda (e r w s mod) | |
2369 | (syntax-case e () | |
2370 | ((_ test then) | |
2371 | (build-conditional | |
2372 | s | |
78a47455 AW |
2373 | (expand #'test r w mod) |
2374 | (expand #'then r w mod) | |
8fad25c2 AW |
2375 | (build-void no-source))) |
2376 | ((_ test then else) | |
2377 | (build-conditional | |
2378 | s | |
78a47455 AW |
2379 | (expand #'test r w mod) |
2380 | (expand #'then r w mod) | |
2381 | (expand #'else r w mod)))))) | |
8fad25c2 AW |
2382 | |
2383 | (global-extend 'core 'with-fluids | |
2384 | (lambda (e r w s mod) | |
2385 | (syntax-case e () | |
2386 | ((_ ((fluid val) ...) b b* ...) | |
2387 | (build-dynlet | |
2388 | s | |
78a47455 AW |
2389 | (map (lambda (x) (expand x r w mod)) #'(fluid ...)) |
2390 | (map (lambda (x) (expand x r w mod)) #'(val ...)) | |
2391 | (expand-body #'(b b* ...) | |
2392 | (source-wrap e w s mod) r w mod)))))) | |
6360c1d4 | 2393 | |
8fad25c2 AW |
2394 | (global-extend 'begin 'begin '()) |
2395 | ||
2396 | (global-extend 'define 'define '()) | |
2397 | ||
2398 | (global-extend 'define-syntax 'define-syntax '()) | |
c2d822de | 2399 | (global-extend 'define-syntax-parameter 'define-syntax-parameter '()) |
8fad25c2 AW |
2400 | |
2401 | (global-extend 'eval-when 'eval-when '()) | |
2402 | ||
2403 | (global-extend 'core 'syntax-case | |
2404 | (let () | |
2405 | (define convert-pattern | |
2406 | ;; accepts pattern & keys | |
2407 | ;; returns $sc-dispatch pattern & ids | |
2408 | (lambda (pattern keys) | |
2409 | (define cvt* | |
2410 | (lambda (p* n ids) | |
0ed9680f SIT |
2411 | (if (not (pair? p*)) |
2412 | (cvt p* n ids) | |
8fad25c2 AW |
2413 | (call-with-values |
2414 | (lambda () (cvt* (cdr p*) n ids)) | |
2415 | (lambda (y ids) | |
2416 | (call-with-values | |
2417 | (lambda () (cvt (car p*) n ids)) | |
2418 | (lambda (x ids) | |
2419 | (values (cons x y) ids)))))))) | |
0ed9680f SIT |
2420 | |
2421 | (define (v-reverse x) | |
2422 | (let loop ((r '()) (x x)) | |
2423 | (if (not (pair? x)) | |
2424 | (values r x) | |
2425 | (loop (cons (car x) r) (cdr x))))) | |
2426 | ||
8fad25c2 AW |
2427 | (define cvt |
2428 | (lambda (p n ids) | |
2429 | (if (id? p) | |
2430 | (cond | |
2431 | ((bound-id-member? p keys) | |
2432 | (values (vector 'free-id p) ids)) | |
2433 | ((free-id=? p #'_) | |
2434 | (values '_ ids)) | |
2435 | (else | |
2436 | (values 'any (cons (cons p n) ids)))) | |
2437 | (syntax-case p () | |
2438 | ((x dots) | |
2439 | (ellipsis? (syntax dots)) | |
2440 | (call-with-values | |
2441 | (lambda () (cvt (syntax x) (fx+ n 1) ids)) | |
2442 | (lambda (p ids) | |
2443 | (values (if (eq? p 'any) 'each-any (vector 'each p)) | |
2444 | ids)))) | |
0ed9680f | 2445 | ((x dots . ys) |
8fad25c2 AW |
2446 | (ellipsis? (syntax dots)) |
2447 | (call-with-values | |
0ed9680f | 2448 | (lambda () (cvt* (syntax ys) n ids)) |
8fad25c2 AW |
2449 | (lambda (ys ids) |
2450 | (call-with-values | |
2451 | (lambda () (cvt (syntax x) (+ n 1) ids)) | |
2452 | (lambda (x ids) | |
0ed9680f SIT |
2453 | (call-with-values |
2454 | (lambda () (v-reverse ys)) | |
2455 | (lambda (ys e) | |
2456 | (values `#(each+ ,x ,ys ,e) | |
2457 | ids)))))))) | |
8fad25c2 AW |
2458 | ((x . y) |
2459 | (call-with-values | |
2460 | (lambda () (cvt (syntax y) n ids)) | |
2461 | (lambda (y ids) | |
2462 | (call-with-values | |
2463 | (lambda () (cvt (syntax x) n ids)) | |
2464 | (lambda (x ids) | |
2465 | (values (cons x y) ids)))))) | |
2466 | (() (values '() ids)) | |
2467 | (#(x ...) | |
2468 | (call-with-values | |
2469 | (lambda () (cvt (syntax (x ...)) n ids)) | |
2470 | (lambda (p ids) (values (vector 'vector p) ids)))) | |
2471 | (x (values (vector 'atom (strip p empty-wrap)) ids)))))) | |
2472 | (cvt pattern 0 '()))) | |
2473 | ||
2474 | (define build-dispatch-call | |
2475 | (lambda (pvars exp y r mod) | |
2476 | (let ((ids (map car pvars)) (levels (map cdr pvars))) | |
2477 | (let ((labels (gen-labels ids)) (new-vars (map gen-var ids))) | |
a881a4ae AW |
2478 | (build-primcall |
2479 | no-source | |
2480 | 'apply | |
2481 | (list (build-simple-lambda no-source (map syntax->datum ids) #f new-vars '() | |
b2208d2e | 2482 | (expand exp |
a881a4ae AW |
2483 | (extend-env |
2484 | labels | |
2485 | (map (lambda (var level) | |
2486 | (make-binding 'syntax `(,var . ,level))) | |
2487 | new-vars | |
2488 | (map cdr pvars)) | |
2489 | r) | |
2490 | (make-binding-wrap ids labels empty-wrap) | |
2491 | mod)) | |
2492 | y)))))) | |
8fad25c2 AW |
2493 | |
2494 | (define gen-clause | |
2495 | (lambda (x keys clauses r pat fender exp mod) | |
2496 | (call-with-values | |
2497 | (lambda () (convert-pattern pat keys)) | |
2498 | (lambda (p pvars) | |
2499 | (cond | |
2500 | ((not (distinct-bound-ids? (map car pvars))) | |
2501 | (syntax-violation 'syntax-case "duplicate pattern variable" pat)) | |
2502 | ((not (and-map (lambda (x) (not (ellipsis? (car x)))) pvars)) | |
2503 | (syntax-violation 'syntax-case "misplaced ellipsis" pat)) | |
2504 | (else | |
2505 | (let ((y (gen-var 'tmp))) | |
2506 | ;; fat finger binding and references to temp variable y | |
7081d4f9 AW |
2507 | (build-call no-source |
2508 | (build-simple-lambda no-source (list 'tmp) #f (list y) '() | |
2509 | (let ((y (build-lexical-reference 'value no-source | |
2510 | 'tmp y))) | |
2511 | (build-conditional no-source | |
2512 | (syntax-case fender () | |
2513 | (#t y) | |
2514 | (_ (build-conditional no-source | |
2515 | y | |
2516 | (build-dispatch-call pvars fender y r mod) | |
2517 | (build-data no-source #f)))) | |
2518 | (build-dispatch-call pvars exp y r mod) | |
2519 | (gen-syntax-case x keys clauses r mod)))) | |
2520 | (list (if (eq? p 'any) | |
a881a4ae AW |
2521 | (build-primcall no-source 'list (list x)) |
2522 | (build-primcall no-source '$sc-dispatch | |
2523 | (list x (build-data no-source p))))))))))))) | |
8fad25c2 AW |
2524 | |
2525 | (define gen-syntax-case | |
2526 | (lambda (x keys clauses r mod) | |
2527 | (if (null? clauses) | |
a881a4ae AW |
2528 | (build-primcall no-source 'syntax-violation |
2529 | (list (build-data no-source #f) | |
2530 | (build-data no-source | |
2531 | "source expression failed to match any pattern") | |
2532 | x)) | |
8fad25c2 AW |
2533 | (syntax-case (car clauses) () |
2534 | ((pat exp) | |
2535 | (if (and (id? #'pat) | |
2536 | (and-map (lambda (x) (not (free-id=? #'pat x))) | |
2537 | (cons #'(... ...) keys))) | |
9120f130 | 2538 | (if (free-id=? #'pat #'_) |
78a47455 | 2539 | (expand #'exp r empty-wrap mod) |
8fad25c2 AW |
2540 | (let ((labels (list (gen-label))) |
2541 | (var (gen-var #'pat))) | |
7081d4f9 AW |
2542 | (build-call no-source |
2543 | (build-simple-lambda | |
2544 | no-source (list (syntax->datum #'pat)) #f (list var) | |
2545 | '() | |
b2208d2e | 2546 | (expand #'exp |
7081d4f9 AW |
2547 | (extend-env labels |
2548 | (list (make-binding 'syntax `(,var . 0))) | |
2549 | r) | |
2550 | (make-binding-wrap #'(pat) | |
2551 | labels empty-wrap) | |
2552 | mod)) | |
2553 | (list x)))) | |
8fad25c2 AW |
2554 | (gen-clause x keys (cdr clauses) r |
2555 | #'pat #t #'exp mod))) | |
2556 | ((pat fender exp) | |
2557 | (gen-clause x keys (cdr clauses) r | |
2558 | #'pat #'fender #'exp mod)) | |
2559 | (_ (syntax-violation 'syntax-case "invalid clause" | |
2560 | (car clauses))))))) | |
2561 | ||
2562 | (lambda (e r w s mod) | |
2563 | (let ((e (source-wrap e w s mod))) | |
2564 | (syntax-case e () | |
2565 | ((_ val (key ...) m ...) | |
2566 | (if (and-map (lambda (x) (and (id? x) (not (ellipsis? x)))) | |
2567 | #'(key ...)) | |
2568 | (let ((x (gen-var 'tmp))) | |
2569 | ;; fat finger binding and references to temp variable x | |
7081d4f9 AW |
2570 | (build-call s |
2571 | (build-simple-lambda no-source (list 'tmp) #f (list x) '() | |
2572 | (gen-syntax-case (build-lexical-reference 'value no-source | |
2573 | 'tmp x) | |
2574 | #'(key ...) #'(m ...) | |
2575 | r | |
2576 | mod)) | |
b2208d2e | 2577 | (list (expand #'val r empty-wrap mod)))) |
8fad25c2 AW |
2578 | (syntax-violation 'syntax-case "invalid literals list" e)))))))) |
2579 | ||
78a47455 | 2580 | ;; The portable macroexpand seeds expand-top's mode m with 'e (for |
8fad25c2 AW |
2581 | ;; evaluating) and esew (which stands for "eval syntax expanders |
2582 | ;; when") with '(eval). In Chez Scheme, m is set to 'c instead of e | |
2583 | ;; if we are compiling a file, and esew is set to | |
2584 | ;; (eval-syntactic-expanders-when), which defaults to the list | |
2585 | ;; '(compile load eval). This means that, by default, top-level | |
2586 | ;; syntactic definitions are evaluated immediately after they are | |
2587 | ;; expanded, and the expanded definitions are also residualized into | |
2588 | ;; the object file if we are compiling a file. | |
2589 | (set! macroexpand | |
2590 | (lambda* (x #:optional (m 'e) (esew '(eval))) | |
78a47455 AW |
2591 | (expand-top-sequence (list x) null-env top-wrap #f m esew |
2592 | (cons 'hygiene (module-name (current-module)))))) | |
8fad25c2 AW |
2593 | |
2594 | (set! identifier? | |
2595 | (lambda (x) | |
2596 | (nonsymbol-id? x))) | |
2597 | ||
2598 | (set! datum->syntax | |
2599 | (lambda (id datum) | |
2600 | (make-syntax-object datum (syntax-object-wrap id) | |
2601 | (syntax-object-module id)))) | |
2602 | ||
2603 | (set! syntax->datum | |
2604 | ;; accepts any object, since syntax objects may consist partially | |
2605 | ;; or entirely of unwrapped, nonsymbolic data | |
2606 | (lambda (x) | |
2607 | (strip x empty-wrap))) | |
2608 | ||
2609 | (set! syntax-source | |
2610 | (lambda (x) (source-annotation x))) | |
2611 | ||
2612 | (set! generate-temporaries | |
2613 | (lambda (ls) | |
2614 | (arg-check list? ls 'generate-temporaries) | |
933c6eb7 | 2615 | (let ((mod (cons 'hygiene (module-name (current-module))))) |
f9685f43 | 2616 | (map (lambda (x) (wrap (gensym "t-") top-wrap mod)) ls)))) |
8fad25c2 AW |
2617 | |
2618 | (set! free-identifier=? | |
2619 | (lambda (x y) | |
2620 | (arg-check nonsymbol-id? x 'free-identifier=?) | |
2621 | (arg-check nonsymbol-id? y 'free-identifier=?) | |
2622 | (free-id=? x y))) | |
2623 | ||
2624 | (set! bound-identifier=? | |
2625 | (lambda (x y) | |
2626 | (arg-check nonsymbol-id? x 'bound-identifier=?) | |
2627 | (arg-check nonsymbol-id? y 'bound-identifier=?) | |
2628 | (bound-id=? x y))) | |
2629 | ||
2630 | (set! syntax-violation | |
8f1870f2 | 2631 | (lambda* (who message form #:optional subform) |
8fad25c2 AW |
2632 | (arg-check (lambda (x) (or (not x) (string? x) (symbol? x))) |
2633 | who 'syntax-violation) | |
2634 | (arg-check string? message 'syntax-violation) | |
8f1870f2 | 2635 | (throw 'syntax-error who message |
bbd1281a MW |
2636 | (or (source-annotation subform) |
2637 | (source-annotation form)) | |
8f1870f2 AW |
2638 | (strip form empty-wrap) |
2639 | (and subform (strip subform empty-wrap))))) | |
8fad25c2 | 2640 | |
68fcf711 AW |
2641 | (let () |
2642 | (define (syntax-module id) | |
2643 | (arg-check nonsymbol-id? id 'syntax-module) | |
2644 | (cdr (syntax-object-module id))) | |
2645 | ||
2646 | (define (syntax-local-binding id) | |
2647 | (arg-check nonsymbol-id? id 'syntax-local-binding) | |
2648 | (with-transformer-environment | |
2649 | (lambda (e r w s rib mod) | |
2650 | (define (strip-anti-mark w) | |
2651 | (let ((ms (wrap-marks w)) (s (wrap-subst w))) | |
2652 | (if (and (pair? ms) (eq? (car ms) the-anti-mark)) | |
2653 | ;; output is from original text | |
2654 | (make-wrap (cdr ms) (if rib (cons rib (cdr s)) (cdr s))) | |
2655 | ;; output introduced by macro | |
2656 | (make-wrap ms (if rib (cons rib s) s))))) | |
2657 | (call-with-values (lambda () | |
2658 | (resolve-identifier | |
2659 | (syntax-object-expression id) | |
2660 | (strip-anti-mark (syntax-object-wrap id)) | |
2661 | r | |
dfadcf85 AW |
2662 | (syntax-object-module id) |
2663 | ;; FIXME: come up with a better policy for | |
2664 | ;; resolve-syntax-parameters | |
2665 | #t)) | |
68fcf711 AW |
2666 | (lambda (type value mod) |
2667 | (case type | |
2668 | ((lexical) (values 'lexical value)) | |
2669 | ((macro) (values 'macro value)) | |
2670 | ((syntax) (values 'pattern-variable value)) | |
2671 | ((displaced-lexical) (values 'displaced-lexical #f)) | |
2672 | ((global) (values 'global (cons value (cdr mod)))) | |
2673 | (else (values 'other #f)))))))) | |
2674 | ||
2675 | (define (syntax-locally-bound-identifiers id) | |
2676 | (arg-check nonsymbol-id? id 'syntax-locally-bound-identifiers) | |
2677 | (locally-bound-identifiers (syntax-object-wrap id) | |
2678 | (syntax-object-module id))) | |
2679 | ||
2680 | ;; Using define! instead of set! to avoid warnings at | |
2681 | ;; compile-time, after the variables are stolen away into (system | |
2682 | ;; syntax). See the end of boot-9.scm. | |
2683 | ;; | |
2684 | (define! 'syntax-module syntax-module) | |
2685 | (define! 'syntax-local-binding syntax-local-binding) | |
2686 | (define! 'syntax-locally-bound-identifiers syntax-locally-bound-identifiers)) | |
2687 | ||
8fad25c2 AW |
2688 | ;; $sc-dispatch expects an expression and a pattern. If the expression |
2689 | ;; matches the pattern a list of the matching expressions for each | |
2690 | ;; "any" is returned. Otherwise, #f is returned. (This use of #f will | |
2691 | ;; not work on r4rs implementations that violate the ieee requirement | |
2692 | ;; that #f and () be distinct.) | |
2693 | ||
2694 | ;; The expression is matched with the pattern as follows: | |
2695 | ||
2696 | ;; pattern: matches: | |
2697 | ;; () empty list | |
2698 | ;; any anything | |
2699 | ;; (<pattern>1 . <pattern>2) (<pattern>1 . <pattern>2) | |
2700 | ;; each-any (any*) | |
2701 | ;; #(free-id <key>) <key> with free-identifier=? | |
2702 | ;; #(each <pattern>) (<pattern>*) | |
2703 | ;; #(each+ p1 (p2_1 ... p2_n) p3) (p1* (p2_n ... p2_1) . p3) | |
2704 | ;; #(vector <pattern>) (list->vector <pattern>) | |
2705 | ;; #(atom <object>) <object> with "equal?" | |
2706 | ||
2707 | ;; Vector cops out to pair under assumption that vectors are rare. If | |
2708 | ;; not, should convert to: | |
2709 | ;; #(vector <pattern>*) #(<pattern>*) | |
2710 | ||
2711 | (let () | |
2712 | ||
2713 | (define match-each | |
2714 | (lambda (e p w mod) | |
aa3819aa AR |
2715 | (cond |
2716 | ((pair? e) | |
8fad25c2 AW |
2717 | (let ((first (match (car e) p w '() mod))) |
2718 | (and first | |
2719 | (let ((rest (match-each (cdr e) p w mod))) | |
2720 | (and rest (cons first rest)))))) | |
2721 | ((null? e) '()) | |
aa3819aa | 2722 | ((syntax-object? e) |
8fad25c2 AW |
2723 | (match-each (syntax-object-expression e) |
2724 | p | |
2725 | (join-wraps w (syntax-object-wrap e)) | |
2726 | (syntax-object-module e))) | |
2727 | (else #f)))) | |
2728 | ||
2729 | (define match-each+ | |
2730 | (lambda (e x-pat y-pat z-pat w r mod) | |
2731 | (let f ((e e) (w w)) | |
c3ae0ed4 | 2732 | (cond |
8fad25c2 AW |
2733 | ((pair? e) |
2734 | (call-with-values (lambda () (f (cdr e) w)) | |
2735 | (lambda (xr* y-pat r) | |
2736 | (if r | |
2737 | (if (null? y-pat) | |
2738 | (let ((xr (match (car e) x-pat w '() mod))) | |
2739 | (if xr | |
2740 | (values (cons xr xr*) y-pat r) | |
2741 | (values #f #f #f))) | |
2742 | (values | |
2743 | '() | |
2744 | (cdr y-pat) | |
2745 | (match (car e) (car y-pat) w r mod))) | |
2746 | (values #f #f #f))))) | |
c3ae0ed4 | 2747 | ((syntax-object? e) |
8fad25c2 AW |
2748 | (f (syntax-object-expression e) (join-wraps w e))) |
2749 | (else | |
2750 | (values '() y-pat (match e z-pat w r mod))))))) | |
2751 | ||
2752 | (define match-each-any | |
2753 | (lambda (e w mod) | |
2754 | (cond | |
2755 | ((pair? e) | |
2756 | (let ((l (match-each-any (cdr e) w mod))) | |
2757 | (and l (cons (wrap (car e) w mod) l)))) | |
2758 | ((null? e) '()) | |
2759 | ((syntax-object? e) | |
2760 | (match-each-any (syntax-object-expression e) | |
2761 | (join-wraps w (syntax-object-wrap e)) | |
2762 | mod)) | |
2763 | (else #f)))) | |
2764 | ||
2765 | (define match-empty | |
2766 | (lambda (p r) | |
2767 | (cond | |
2768 | ((null? p) r) | |
2769 | ((eq? p '_) r) | |
2770 | ((eq? p 'any) (cons '() r)) | |
2771 | ((pair? p) (match-empty (car p) (match-empty (cdr p) r))) | |
2772 | ((eq? p 'each-any) (cons '() r)) | |
2773 | (else | |
2774 | (case (vector-ref p 0) | |
2775 | ((each) (match-empty (vector-ref p 1) r)) | |
2776 | ((each+) (match-empty (vector-ref p 1) | |
2777 | (match-empty | |
2778 | (reverse (vector-ref p 2)) | |
2779 | (match-empty (vector-ref p 3) r)))) | |
2780 | ((free-id atom) r) | |
2781 | ((vector) (match-empty (vector-ref p 1) r))))))) | |
2782 | ||
2783 | (define combine | |
2784 | (lambda (r* r) | |
2785 | (if (null? (car r*)) | |
2786 | r | |
2787 | (cons (map car r*) (combine (map cdr r*) r))))) | |
2788 | ||
2789 | (define match* | |
2790 | (lambda (e p w r mod) | |
2791 | (cond | |
2792 | ((null? p) (and (null? e) r)) | |
2793 | ((pair? p) | |
2794 | (and (pair? e) (match (car e) (car p) w | |
2795 | (match (cdr e) (cdr p) w r mod) | |
2796 | mod))) | |
2797 | ((eq? p 'each-any) | |
2798 | (let ((l (match-each-any e w mod))) (and l (cons l r)))) | |
2799 | (else | |
2800 | (case (vector-ref p 0) | |
2801 | ((each) | |
2802 | (if (null? e) | |
2803 | (match-empty (vector-ref p 1) r) | |
2804 | (let ((l (match-each e (vector-ref p 1) w mod))) | |
2805 | (and l | |
2806 | (let collect ((l l)) | |
2807 | (if (null? (car l)) | |
2808 | r | |
2809 | (cons (map car l) (collect (map cdr l))))))))) | |
2810 | ((each+) | |
2811 | (call-with-values | |
2812 | (lambda () | |
2813 | (match-each+ e (vector-ref p 1) (vector-ref p 2) (vector-ref p 3) w r mod)) | |
2814 | (lambda (xr* y-pat r) | |
2815 | (and r | |
2816 | (null? y-pat) | |
2817 | (if (null? xr*) | |
2818 | (match-empty (vector-ref p 1) r) | |
2819 | (combine xr* r)))))) | |
2820 | ((free-id) (and (id? e) (free-id=? (wrap e w mod) (vector-ref p 1)) r)) | |
2821 | ((atom) (and (equal? (vector-ref p 1) (strip e w)) r)) | |
2822 | ((vector) | |
2823 | (and (vector? e) | |
2824 | (match (vector->list e) (vector-ref p 1) w r mod)))))))) | |
2825 | ||
2826 | (define match | |
2827 | (lambda (e p w r mod) | |
2828 | (cond | |
2829 | ((not r) #f) | |
2830 | ((eq? p '_) r) | |
2831 | ((eq? p 'any) (cons (wrap e w mod) r)) | |
2832 | ((syntax-object? e) | |
2833 | (match* | |
2834 | (syntax-object-expression e) | |
2835 | p | |
2836 | (join-wraps w (syntax-object-wrap e)) | |
2837 | r | |
2838 | (syntax-object-module e))) | |
2839 | (else (match* e p w r mod))))) | |
2840 | ||
2841 | (set! $sc-dispatch | |
2842 | (lambda (e p) | |
2843 | (cond | |
2844 | ((eq? p 'any) (list e)) | |
2845 | ((eq? p '_) '()) | |
2846 | ((syntax-object? e) | |
2847 | (match* (syntax-object-expression e) | |
2848 | p (syntax-object-wrap e) '() (syntax-object-module e))) | |
2849 | (else (match* e p empty-wrap '() #f)))))))) | |
80f225df | 2850 | |
a63812a2 JB |
2851 | |
2852 | (define-syntax with-syntax | |
2853 | (lambda (x) | |
2854 | (syntax-case x () | |
2855 | ((_ () e1 e2 ...) | |
f929b9e5 | 2856 | #'(let () e1 e2 ...)) |
a63812a2 | 2857 | ((_ ((out in)) e1 e2 ...) |
f929b9e5 AW |
2858 | #'(syntax-case in () |
2859 | (out (let () e1 e2 ...)))) | |
a63812a2 | 2860 | ((_ ((out in) ...) e1 e2 ...) |
c3ae0ed4 | 2861 | #'(syntax-case (list in ...) () |
f929b9e5 | 2862 | ((out ...) (let () e1 e2 ...))))))) |
a63812a2 JB |
2863 | |
2864 | (define-syntax syntax-rules | |
1af6d2a7 MW |
2865 | (lambda (xx) |
2866 | (syntax-case xx () | |
a63812a2 | 2867 | ((_ (k ...) ((keyword . pattern) template) ...) |
c3ae0ed4 | 2868 | #'(lambda (x) |
a5e95abe | 2869 | ;; embed patterns as procedure metadata |
44d65b23 AW |
2870 | #((macro-type . syntax-rules) |
2871 | (patterns pattern ...)) | |
2872 | (syntax-case x (k ...) | |
f698b728 | 2873 | ((_ . pattern) #'template) |
44d65b23 AW |
2874 | ...))) |
2875 | ((_ (k ...) docstring ((keyword . pattern) template) ...) | |
2876 | (string? (syntax->datum #'docstring)) | |
2877 | #'(lambda (x) | |
2878 | ;; the same, but allow a docstring | |
2879 | docstring | |
a5e95abe AW |
2880 | #((macro-type . syntax-rules) |
2881 | (patterns pattern ...)) | |
c3ae0ed4 | 2882 | (syntax-case x (k ...) |
f698b728 | 2883 | ((_ . pattern) #'template) |
c3ae0ed4 | 2884 | ...)))))) |
a63812a2 | 2885 | |
dea14eb9 AW |
2886 | (define-syntax define-syntax-rule |
2887 | (lambda (x) | |
2888 | (syntax-case x () | |
2889 | ((_ (name . pattern) template) | |
2890 | #'(define-syntax name | |
2891 | (syntax-rules () | |
2892 | ((_ . pattern) template)))) | |
2893 | ((_ (name . pattern) docstring template) | |
2894 | (string? (syntax->datum #'docstring)) | |
2895 | #'(define-syntax name | |
2896 | (syntax-rules () | |
2897 | docstring | |
2898 | ((_ . pattern) template))))))) | |
2899 | ||
a63812a2 JB |
2900 | (define-syntax let* |
2901 | (lambda (x) | |
2902 | (syntax-case x () | |
2903 | ((let* ((x v) ...) e1 e2 ...) | |
c3ae0ed4 AW |
2904 | (and-map identifier? #'(x ...)) |
2905 | (let f ((bindings #'((x v) ...))) | |
a63812a2 | 2906 | (if (null? bindings) |
c3ae0ed4 | 2907 | #'(let () e1 e2 ...) |
a63812a2 JB |
2908 | (with-syntax ((body (f (cdr bindings))) |
2909 | (binding (car bindings))) | |
c3ae0ed4 | 2910 | #'(let (binding) body)))))))) |
a63812a2 | 2911 | |
a63812a2 | 2912 | (define-syntax quasiquote |
0f550375 AW |
2913 | (let () |
2914 | (define (quasi p lev) | |
2915 | (syntax-case p (unquote quasiquote) | |
2916 | ((unquote p) | |
2917 | (if (= lev 0) | |
2918 | #'("value" p) | |
2919 | (quasicons #'("quote" unquote) (quasi #'(p) (- lev 1))))) | |
2920 | ((quasiquote p) (quasicons #'("quote" quasiquote) (quasi #'(p) (+ lev 1)))) | |
2921 | ((p . q) | |
2922 | (syntax-case #'p (unquote unquote-splicing) | |
2923 | ((unquote p ...) | |
2924 | (if (= lev 0) | |
2925 | (quasilist* #'(("value" p) ...) (quasi #'q lev)) | |
2926 | (quasicons | |
2927 | (quasicons #'("quote" unquote) (quasi #'(p ...) (- lev 1))) | |
2928 | (quasi #'q lev)))) | |
2929 | ((unquote-splicing p ...) | |
2930 | (if (= lev 0) | |
2931 | (quasiappend #'(("value" p) ...) (quasi #'q lev)) | |
2932 | (quasicons | |
2933 | (quasicons #'("quote" unquote-splicing) (quasi #'(p ...) (- lev 1))) | |
2934 | (quasi #'q lev)))) | |
2935 | (_ (quasicons (quasi #'p lev) (quasi #'q lev))))) | |
2936 | (#(x ...) (quasivector (vquasi #'(x ...) lev))) | |
2937 | (p #'("quote" p)))) | |
2938 | (define (vquasi p lev) | |
2939 | (syntax-case p () | |
2940 | ((p . q) | |
2941 | (syntax-case #'p (unquote unquote-splicing) | |
2942 | ((unquote p ...) | |
2943 | (if (= lev 0) | |
2944 | (quasilist* #'(("value" p) ...) (vquasi #'q lev)) | |
2945 | (quasicons | |
2946 | (quasicons #'("quote" unquote) (quasi #'(p ...) (- lev 1))) | |
2947 | (vquasi #'q lev)))) | |
2948 | ((unquote-splicing p ...) | |
2949 | (if (= lev 0) | |
2950 | (quasiappend #'(("value" p) ...) (vquasi #'q lev)) | |
2951 | (quasicons | |
2952 | (quasicons | |
2953 | #'("quote" unquote-splicing) | |
2954 | (quasi #'(p ...) (- lev 1))) | |
2955 | (vquasi #'q lev)))) | |
2956 | (_ (quasicons (quasi #'p lev) (vquasi #'q lev))))) | |
2957 | (() #'("quote" ())))) | |
2958 | (define (quasicons x y) | |
2959 | (with-syntax ((x x) (y y)) | |
2960 | (syntax-case #'y () | |
2961 | (("quote" dy) | |
2962 | (syntax-case #'x () | |
2963 | (("quote" dx) #'("quote" (dx . dy))) | |
2964 | (_ (if (null? #'dy) #'("list" x) #'("list*" x y))))) | |
2965 | (("list" . stuff) #'("list" x . stuff)) | |
2966 | (("list*" . stuff) #'("list*" x . stuff)) | |
2967 | (_ #'("list*" x y))))) | |
2968 | (define (quasiappend x y) | |
2969 | (syntax-case y () | |
2970 | (("quote" ()) | |
2971 | (cond | |
2972 | ((null? x) #'("quote" ())) | |
2973 | ((null? (cdr x)) (car x)) | |
2974 | (else (with-syntax (((p ...) x)) #'("append" p ...))))) | |
2975 | (_ | |
2976 | (cond | |
2977 | ((null? x) y) | |
2978 | (else (with-syntax (((p ...) x) (y y)) #'("append" p ... y))))))) | |
2979 | (define (quasilist* x y) | |
2980 | (let f ((x x)) | |
2981 | (if (null? x) | |
2982 | y | |
2983 | (quasicons (car x) (f (cdr x)))))) | |
2984 | (define (quasivector x) | |
2985 | (syntax-case x () | |
2986 | (("quote" (x ...)) #'("quote" #(x ...))) | |
2987 | (_ | |
2988 | (let f ((y x) (k (lambda (ls) #`("vector" #,@ls)))) | |
2989 | (syntax-case y () | |
2990 | (("quote" (y ...)) (k #'(("quote" y) ...))) | |
2991 | (("list" y ...) (k #'(y ...))) | |
2992 | (("list*" y ... z) (f #'z (lambda (ls) (k (append #'(y ...) ls))))) | |
2993 | (else #`("list->vector" #,x))))))) | |
2994 | (define (emit x) | |
2995 | (syntax-case x () | |
2996 | (("quote" x) #''x) | |
2997 | (("list" x ...) #`(list #,@(map emit #'(x ...)))) | |
2998 | ;; could emit list* for 3+ arguments if implementation supports | |
2999 | ;; list* | |
3000 | (("list*" x ... y) | |
3001 | (let f ((x* #'(x ...))) | |
3002 | (if (null? x*) | |
3003 | (emit #'y) | |
3004 | #`(cons #,(emit (car x*)) #,(f (cdr x*)))))) | |
3005 | (("append" x ...) #`(append #,@(map emit #'(x ...)))) | |
3006 | (("vector" x ...) #`(vector #,@(map emit #'(x ...)))) | |
3007 | (("list->vector" x) #`(list->vector #,(emit #'x))) | |
3008 | (("value" x) #'x))) | |
a63812a2 | 3009 | (lambda (x) |
0f550375 AW |
3010 | (syntax-case x () |
3011 | ;; convert to intermediate language, combining introduced (but | |
3012 | ;; not unquoted source) quote expressions where possible and | |
3013 | ;; choosing optimal construction code otherwise, then emit | |
3014 | ;; Scheme code corresponding to the intermediate language forms. | |
3015 | ((_ e) (emit (quasi #'e 0))))))) | |
a63812a2 JB |
3016 | |
3017 | (define-syntax include | |
3018 | (lambda (x) | |
3019 | (define read-file | |
3020 | (lambda (fn k) | |
3021 | (let ((p (open-input-file fn))) | |
df0f5295 LC |
3022 | (let f ((x (read p)) |
3023 | (result '())) | |
a63812a2 | 3024 | (if (eof-object? x) |
df0f5295 LC |
3025 | (begin |
3026 | (close-input-port p) | |
3027 | (reverse result)) | |
3028 | (f (read p) | |
3029 | (cons (datum->syntax k x) result))))))) | |
a63812a2 JB |
3030 | (syntax-case x () |
3031 | ((k filename) | |
c3ae0ed4 | 3032 | (let ((fn (syntax->datum #'filename))) |
9846796b | 3033 | (with-syntax (((exp ...) (read-file fn #'filename))) |
c3ae0ed4 | 3034 | #'(begin exp ...))))))) |
a63812a2 | 3035 | |
d89fae24 AW |
3036 | (define-syntax include-from-path |
3037 | (lambda (x) | |
3038 | (syntax-case x () | |
3039 | ((k filename) | |
3040 | (let ((fn (syntax->datum #'filename))) | |
9846796b AW |
3041 | (with-syntax ((fn (datum->syntax |
3042 | #'filename | |
3043 | (or (%search-load-path fn) | |
3044 | (syntax-violation 'include-from-path | |
3045 | "file not found in path" | |
3046 | x #'filename))))) | |
d89fae24 AW |
3047 | #'(include fn))))))) |
3048 | ||
a63812a2 | 3049 | (define-syntax unquote |
6a952e0e | 3050 | (lambda (x) |
0f550375 AW |
3051 | (syntax-violation 'unquote |
3052 | "expression not valid outside of quasiquote" | |
3053 | x))) | |
a63812a2 JB |
3054 | |
3055 | (define-syntax unquote-splicing | |
6a952e0e | 3056 | (lambda (x) |
0f550375 AW |
3057 | (syntax-violation 'unquote-splicing |
3058 | "expression not valid outside of quasiquote" | |
3059 | x))) | |
a63812a2 | 3060 | |
bfccdcd5 AW |
3061 | (define (make-variable-transformer proc) |
3062 | (if (procedure? proc) | |
3063 | (let ((trans (lambda (x) | |
3064 | #((macro-type . variable-transformer)) | |
3065 | (proc x)))) | |
3066 | (set-procedure-property! trans 'variable-transformer #t) | |
3067 | trans) | |
3068 | (error "variable transformer not a procedure" proc))) | |
3069 | ||
a63812a2 | 3070 | (define-syntax identifier-syntax |
1af6d2a7 MW |
3071 | (lambda (xx) |
3072 | (syntax-case xx (set!) | |
a63812a2 | 3073 | ((_ e) |
c3ae0ed4 | 3074 | #'(lambda (x) |
a5e95abe | 3075 | #((macro-type . identifier-syntax)) |
a63812a2 JB |
3076 | (syntax-case x () |
3077 | (id | |
c3ae0ed4 AW |
3078 | (identifier? #'id) |
3079 | #'e) | |
a63812a2 | 3080 | ((_ x (... ...)) |
bfccdcd5 AW |
3081 | #'(e x (... ...)))))) |
3082 | ((_ (id exp1) ((set! var val) exp2)) | |
3083 | (and (identifier? #'id) (identifier? #'var)) | |
3084 | #'(make-variable-transformer | |
3085 | (lambda (x) | |
3086 | #((macro-type . variable-transformer)) | |
3087 | (syntax-case x (set!) | |
3088 | ((set! var val) #'exp2) | |
3089 | ((id x (... ...)) #'(exp1 x (... ...))) | |
3090 | (id (identifier? #'id) #'exp1)))))))) | |
97bc28b6 AW |
3091 | |
3092 | (define-syntax define* | |
64fa96ef AW |
3093 | (lambda (x) |
3094 | (syntax-case x () | |
3095 | ((_ (id . args) b0 b1 ...) | |
3096 | #'(define id (lambda* args b0 b1 ...))) | |
9120f130 | 3097 | ((_ id val) (identifier? #'id) |
64fa96ef | 3098 | #'(define id val))))) |