1 ;;; geiser-syntax.el -- utilities for parsing scheme syntax
3 ;; Copyright (C) 2009, 2010 Jose Antonio Ortega Ruiz
5 ;; This program is free software; you can redistribute it and/or
6 ;; modify it under the terms of the Modified BSD License. You should
7 ;; have received a copy of the license along with this program. If
8 ;; not, see <http://www.xfree86.org/3.3.6/COPYRIGHT2.html#5>.
10 ;; Start date: Sun Feb 08, 2009 15:03
14 (require 'geiser-impl
)
15 (require 'geiser-popup
)
16 (require 'geiser-base
)
20 (eval-when-compile (require 'cl
))
25 (defmacro geiser-syntax--scheme-indent
(&rest pairs
)
26 `(progn ,@(mapcar (lambda (p)
27 `(put ',(car p
) 'scheme-indent-function
',(cadr p
)))
30 (geiser-syntax--scheme-indent
64 (parameterize-break 1)
88 ;;; Extra syntax keywords
89 (defconst geiser-syntax--keywords
90 '(("\\[\\(else\\)\\>" .
1)
91 ("(\\(parameterize\\)\\>" .
1)))
93 (font-lock-add-keywords 'scheme-mode geiser-syntax--keywords
)
95 (geiser-impl--define-caller geiser-syntax--impl-kws keywords
()
96 "A variable (or thunk returning a value) giving additional,
97 implementation-specific entries for font-lock-keywords.")
99 (defun geiser-syntax--add-kws ()
100 (let ((kw (geiser-syntax--impl-kws geiser-impl--implementation
)))
101 (when kw
(font-lock-add-keywords nil kw
))))
104 ;;; A simple scheme reader
106 (defvar geiser-syntax--read
/buffer-limit nil
)
108 (defsubst geiser-syntax--read
/eos
()
110 (and geiser-syntax--read
/buffer-limit
111 (<= geiser-syntax--read
/buffer-limit
(point)))))
113 (defsubst geiser-syntax--read
/next-char
()
114 (unless (geiser-syntax--read/eos
)
118 (defsubst geiser-syntax--read
/token
(token)
119 (geiser-syntax--read/next-char
)
120 (if (listp token
) token
(list token
)))
122 (defsubst geiser-syntax--read
/elisp
()
123 (ignore-errors (read (current-buffer))))
125 (defun geiser-syntax--read/symbol
()
126 (with-syntax-table scheme-mode-syntax-table
127 (when (re-search-forward "\\(\\sw\\|\\s_\\)+" nil t
)
128 (make-symbol (match-string-no-properties 0)))))
130 (defun geiser-syntax--read/matching
(open close
)
133 (while (and (> count
0)
134 (geiser-syntax--read/next-char
))
135 (cond ((looking-at-p open
) (setq count
(1+ count
)))
136 ((looking-at-p close
) (setq count
(1- count
)))))
137 (buffer-substring-no-properties p
(point))))
139 (defsubst geiser-syntax--read
/unprintable
()
140 (geiser-syntax--read/token
141 (cons 'unprintable
(geiser-syntax--read/matching
"<" ">"))))
143 (defun geiser-syntax--read/skip-comment
()
144 (while (and (geiser-syntax--read/next-char
)
145 (nth 8 (syntax-ppss))))
146 (geiser-syntax--read/next-token
))
148 (defun geiser-syntax--read/next-token
()
149 (skip-syntax-forward "->")
150 (if (geiser-syntax--read/eos
) '(eob)
152 (?\
; (geiser-syntax--read/skip-comment))
153 ((?\
( ?\
[) (geiser-syntax--read/token
'lparen
))
154 ((?\
) ?\
]) (geiser-syntax--read/token
'rparen
))
155 (?.
(if (memq (car (syntax-after (1+ (point)))) '(0 11 12))
156 (geiser-syntax--read/token
'dot
)
157 (cons 'atom
(geiser-syntax--read/elisp
))))
158 (?\
# (case (geiser-syntax--read/next-char
)
160 (?|
(geiser-syntax--read/skip-comment
))
161 (?
: (if (geiser-syntax--read/next-char
)
162 (cons 'kwd
(geiser-syntax--read/symbol
))
164 (?
\\ (cons 'char
(geiser-syntax--read/elisp
)))
165 (?\
( (geiser-syntax--read/token
'vectorb
))
166 (?\
< (geiser-syntax--read/unprintable
))
167 ((?
' ?
` ?
,) (geiser-syntax--read/next-token
))
168 (t (let ((tok (geiser-syntax--read/symbol
)))
169 (cond ((equal (symbol-name tok
) "t") '(boolean .
:t
))
170 ((equal (symbol-name tok
) "f") '(boolean .
:f
))
171 (tok (cons 'atom
(make-symbol (format "#%s" tok
))))
172 (t (geiser-syntax--read/next-token
)))))))
173 (?
\' (geiser-syntax--read/token
'(quote . quote
)))
174 (?\
` (geiser-syntax--read/token
175 `(backquote .
,backquote-backquote-symbol
)))
176 (?
, (if (eq (geiser-syntax--read/next-char
) ?
@)
177 (geiser-syntax--read/token
178 `(splice .
,backquote-splice-symbol
))
179 `(unquote .
,backquote-unquote-symbol
)))
180 (?
\" (cons 'string
(geiser-syntax--read/elisp
)))
181 (t (cons 'atom
(geiser-syntax--read/symbol
))))))
183 (defsubst geiser-syntax--read
/match
(&rest tks
)
184 (let ((token (geiser-syntax--read/next-token
)))
185 (if (memq (car token
) tks
) token
186 (error "Unexpected token: %s" token
))))
188 (defsubst geiser-syntax--read
/skip-until
(&rest tks
)
190 (while (and (not (memq (car token
) tks
))
191 (not (eq (car token
) 'eob
)))
192 (setq token
(geiser-syntax--read/next-token
)))
195 (defsubst geiser-syntax--read
/try
(&rest tks
)
197 (tk (ignore-errors (apply 'geiser-syntax--read
/match tks
))))
198 (unless tk
(goto-char p
))
201 (defun geiser-syntax--read/list
()
202 (cond ((geiser-syntax--read/try
'dot
)
203 (let ((tail (geiser-syntax--read)))
204 (geiser-syntax--read/skip-until
'eob
'rparen
)
206 ((geiser-syntax--read/try
'rparen
'eob
) nil
)
207 (t (cons (geiser-syntax--read)
208 (geiser-syntax--read/list
)))))
210 (defun geiser-syntax--read ()
211 (let ((token (geiser-syntax--read/next-token
))
212 (max-lisp-eval-depth (max max-lisp-eval-depth
3000)))
215 (lparen (geiser-syntax--read/list
))
216 (vectorb (apply 'vector
(geiser-syntax--read/list
)))
217 ((quote backquote unquote splice
) (list (cdr token
)
218 (geiser-syntax--read)))
219 (kwd (make-symbol (format ":%s" (cdr token
))))
220 (unprintable (format "#<%s>" (cdr token
)))
221 ((char string atom
) (cdr token
))
222 (boolean (cdr token
))
223 (t (error "Reading scheme syntax: unexpected token: %s" token
)))))
225 (defun geiser-syntax--read-from-string (string &optional start end
)
226 (when (stringp string
)
227 (let* ((start (or start
0))
228 (end (or end
(length string
)))
229 (max-lisp-eval-depth (max max-lisp-eval-depth
(- end start
))))
231 (save-excursion (insert string
))
232 (cons (ignore-errors (geiser-syntax--read)) (point))))))
234 (defsubst geiser-syntax--form-after-point
(&optional boundary
)
235 (let ((geiser-syntax--read/buffer-limit
(and (numberp boundary
) boundary
)))
236 (save-excursion (values (geiser-syntax--read) (point)))))
238 (defun geiser-syntax--mapconcat (fun lst sep
)
239 (cond ((null lst
) "")
240 ((not (listp lst
)) (format ".%s%s" sep
(funcall fun lst
)))
241 ((null (cdr lst
)) (format "%s" (funcall fun
(car lst
))))
243 (funcall fun
(car lst
))
245 (geiser-syntax--mapconcat fun
(cdr lst
) sep
)))))
247 (defun geiser-syntax--display (a)
248 (cond ((null a
) "()")
251 ((geiser-syntax--keywordp a
) (format "#%s" a
))
252 ((symbolp a
) (format "%s" a
))
253 ((equal a
"...") "...")
254 ((stringp a
) (format "%S" a
))
255 ((and (listp a
) (symbolp (car a
))
256 (equal (symbol-name (car a
)) "quote"))
257 (format "'%s" (geiser-syntax--display (cadr a
))))
260 (geiser-syntax--mapconcat 'geiser-syntax--display a
" ")))
261 (t (format "%s" a
))))
266 (defsubst geiser-syntax--symbol-at-point
()
267 (and (not (nth 8 (syntax-ppss)))
268 (let ((s (thing-at-point 'symbol
)))
271 (make-symbol (substring-no-properties s
))))))
273 (defsubst geiser-syntax--skip-comment
/string
()
274 (let ((pos (nth 8 (syntax-ppss))))
275 (goto-char (or pos
(point)))
278 (defsubst geiser-syntax--nesting-level
()
279 (or (nth 0 (syntax-ppss)) 0))
281 (defsubst geiser-syntax--pair-length
(p)
282 (if (cdr (last p
)) (1+ (safe-length p
)) (length p
)))
284 (defun geiser-syntax--shallow-form (boundary)
285 (when (looking-at-p "\\s(")
290 (while (< (point) boundary
)
291 (skip-syntax-forward "-<>")
292 (when (<= (point) boundary
)
294 (let ((s (thing-at-point 'symbol
)))
295 (cond ((not s
) (push s elems
))
296 ((not (equal "." s
)) (push (make-symbol s
) elems
)))))))
299 (defsubst geiser-syntax--keywordp
(s)
300 (and s
(symbolp s
) (string-match "^:.+" (symbol-name s
))))
302 (defsubst geiser-syntax--symbol-eq
(s0 s1
)
303 (and (symbolp s0
) (symbolp s1
) (equal (symbol-name s0
) (symbol-name s1
))))
305 (defun geiser-syntax--scan-sexps (&optional begin
)
306 (let* ((fst (geiser-syntax--symbol-at-point))
307 (smth (or fst
(not (looking-at-p "[\s \s)\s>\s<\n]"))))
308 (path (and fst
`((,fst
0)))))
310 (while (not (zerop (geiser-syntax--nesting-level)))
311 (let ((boundary (point)))
312 (geiser-syntax--skip-comment/string
)
314 (let ((form (geiser-syntax--shallow-form boundary
)))
315 (when (and (listp form
) (car form
) (symbolp (car form
)))
316 (let* ((len (geiser-syntax--pair-length form
))
317 (pos (if smth
(1- len
) (progn (setq smth t
) len
)))
318 (prev (and (> pos
1) (nth (1- pos
) form
)))
319 (prev (and (geiser-syntax--keywordp prev
)
321 (push `(,(car form
) ,pos
,@prev
) path
)))))))
322 (mapcar (lambda (e) (cons (format "%S" (car e
)) (cdr e
)))
325 (defsubst geiser-syntax--binding-form-p
(bfs sbfs f
)
327 (let ((f (symbol-name f
)))
328 (or (member f
'("define" "define*" "define-syntax"
329 "syntax-rules" "lambda" "case-lambda"
330 "let" "let*" "let-values" "let*-values"
331 "letrec" "letrec*" "parameterize"))
335 (defsubst geiser-syntax--binding-form
*-p
(sbfs f
)
337 (let ((f (symbol-name f
)))
338 (or (member f
'("let*" "let*-values" "letrec" "letrec*"))
341 (defsubst geiser-syntax--if-symbol
(x) (and (symbolp x
) x
))
342 (defsubst geiser-syntax--if-list
(x) (and (listp x
) x
))
344 (defsubst geiser-syntax--normalize
(vars)
346 (let ((i (if (listp i
) (car i
) i
)))
347 (and (symbolp i
) (symbol-name i
))))
350 (defun geiser-syntax--linearize (form)
351 (cond ((not (listp form
)) (list form
))
353 (t (cons (car form
) (geiser-syntax--linearize (cdr form
))))))
355 (defun geiser-syntax--scan-locals (bfs sbfs form nesting locals
)
356 (if (or (null form
) (not (listp form
)))
357 (geiser-syntax--normalize locals
)
358 (if (not (geiser-syntax--binding-form-p bfs sbfs
(car form
)))
359 (geiser-syntax--scan-locals bfs sbfs
362 (let* ((head (car form
))
363 (name (geiser-syntax--if-symbol (cadr form
)))
364 (names (if name
(geiser-syntax--if-list (caddr form
))
365 (geiser-syntax--if-list (cadr form
))))
367 (geiser-syntax--binding-form-p bfs sbfs
(car names
))))
368 (rest (if (and name
(not bns
)) (cdddr form
) (cddr form
)))
369 (use-names (and (or rest
371 (geiser-syntax--binding-form*-p sbfs head
))
373 (when name
(push name locals
))
374 (when (geiser-syntax--symbol-eq head
'case-lambda
)
375 (dolist (n (and (> nesting
0) (caar (last form
))))
376 (when n
(push n locals
)))
377 (setq rest
(and (> nesting
0) (cdr form
)))
378 (setq use-names nil
))
379 (when (geiser-syntax--symbol-eq head
'syntax-rules
)
380 (dolist (n (and (> nesting
0) (cdaar (last form
))))
381 (when n
(push n locals
)))
382 (setq rest
(and (> nesting
0) (cdr form
))))
384 (dolist (n (geiser-syntax--linearize names
))
385 (let ((xs (if (and (listp n
) (listp (car n
))) (car n
) (list n
))))
386 (dolist (x xs
) (when x
(push x locals
))))))
387 (dolist (f (butlast rest
))
389 (geiser-syntax--symbol-eq (car f
) 'define
)
391 (push (cadr f
) locals
)))
392 (geiser-syntax--scan-locals bfs sbfs
393 (car (last (or rest names
)))
397 (defun geiser-syntax--locals-around-point (bfs sbfs
)
398 (when (eq major-mode
'scheme-mode
)
400 (let ((sym (unless (geiser-syntax--skip-comment/string
)
401 (thing-at-point 'symbol
))))
402 (skip-syntax-forward "->")
403 (let ((boundary (point))
404 (nesting (geiser-syntax--nesting-level)))
405 (while (not (zerop (geiser-syntax--nesting-level)))
407 (multiple-value-bind (form end
)
408 (geiser-syntax--form-after-point boundary
)
410 (geiser-syntax--scan-locals bfs
417 ;;; Fontify strings as Scheme code:
419 (defun geiser-syntax--font-lock-buffer ()
420 (let ((name " *geiser font lock*"))
421 (or (get-buffer name
)
422 (let ((buffer (get-buffer-create name
)))
424 (let ((geiser-default-implementation
425 (or geiser-default-implementation
426 (car geiser-active-implementations
))))
430 (defun geiser-syntax--scheme-str (str)
432 (set-buffer (geiser-syntax--font-lock-buffer))
435 (let ((font-lock-verbose nil
)) (font-lock-fontify-buffer))
439 (provide 'geiser-syntax
)
440 ;;; geiser-syntax.el ends here