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 (when (not (and (boundp 'quack-mode
) quack-mode
))
101 (let ((kw (geiser-syntax--impl-kws geiser-impl--implementation
)))
102 (when kw
(font-lock-add-keywords nil kw
)))))
105 ;;; A simple scheme reader
107 (defvar geiser-syntax--read
/buffer-limit nil
)
109 (defsubst geiser-syntax--read
/eos
()
111 (and geiser-syntax--read
/buffer-limit
112 (<= geiser-syntax--read
/buffer-limit
(point)))))
114 (defsubst geiser-syntax--read
/next-char
()
115 (unless (geiser-syntax--read/eos
)
119 (defsubst geiser-syntax--read
/token
(token)
120 (geiser-syntax--read/next-char
)
121 (if (listp token
) token
(list token
)))
123 (defsubst geiser-syntax--read
/elisp
()
124 (ignore-errors (read (current-buffer))))
126 (defun geiser-syntax--read/symbol
()
127 (with-syntax-table scheme-mode-syntax-table
128 (when (re-search-forward "\\(\\sw\\|\\s_\\)+" nil t
)
129 (make-symbol (match-string-no-properties 0)))))
131 (defun geiser-syntax--read/matching
(open close
)
134 (while (and (> count
0)
135 (geiser-syntax--read/next-char
))
136 (cond ((looking-at-p open
) (setq count
(1+ count
)))
137 ((looking-at-p close
) (setq count
(1- count
)))))
138 (buffer-substring-no-properties p
(point))))
140 (defsubst geiser-syntax--read
/unprintable
()
141 (geiser-syntax--read/token
142 (cons 'unprintable
(geiser-syntax--read/matching
"<" ">"))))
144 (defun geiser-syntax--read/skip-comment
()
145 (while (and (geiser-syntax--read/next-char
)
146 (nth 8 (syntax-ppss))))
147 (geiser-syntax--read/next-token
))
149 (defun geiser-syntax--read/next-token
()
150 (skip-syntax-forward "->")
151 (if (geiser-syntax--read/eos
) '(eob)
153 (?\
; (geiser-syntax--read/skip-comment))
154 ((?\
( ?\
[) (geiser-syntax--read/token
'lparen
))
155 ((?\
) ?\
]) (geiser-syntax--read/token
'rparen
))
156 (?.
(if (memq (car (syntax-after (1+ (point)))) '(0 11 12))
157 (geiser-syntax--read/token
'dot
)
158 (cons 'atom
(geiser-syntax--read/elisp
))))
159 (?\
# (case (geiser-syntax--read/next-char
)
161 (?|
(geiser-syntax--read/skip-comment
))
162 (?
: (if (geiser-syntax--read/next-char
)
163 (cons 'kwd
(geiser-syntax--read/symbol
))
165 (?
\\ (cons 'char
(geiser-syntax--read/elisp
)))
166 (?\
( (geiser-syntax--read/token
'vectorb
))
167 (?\
< (geiser-syntax--read/unprintable
))
168 ((?
' ?
` ?
,) (geiser-syntax--read/next-token
))
169 (t (let ((tok (geiser-syntax--read/symbol
)))
170 (cond ((equal (symbol-name tok
) "t") '(boolean .
:t
))
171 ((equal (symbol-name tok
) "f") '(boolean .
:f
))
172 (tok (cons 'atom
(make-symbol (format "#%s" tok
))))
173 (t (geiser-syntax--read/next-token
)))))))
174 (?
\' (geiser-syntax--read/token
'(quote . quote
)))
175 (?\
` (geiser-syntax--read/token
176 `(backquote .
,backquote-backquote-symbol
)))
177 (?
, (if (eq (geiser-syntax--read/next-char
) ?
@)
178 (geiser-syntax--read/token
179 `(splice .
,backquote-splice-symbol
))
180 `(unquote .
,backquote-unquote-symbol
)))
181 (?
\" (cons 'string
(geiser-syntax--read/elisp
)))
182 (t (cons 'atom
(geiser-syntax--read/symbol
))))))
184 (defsubst geiser-syntax--read
/match
(&rest tks
)
185 (let ((token (geiser-syntax--read/next-token
)))
186 (if (memq (car token
) tks
) token
187 (error "Unexpected token: %s" token
))))
189 (defsubst geiser-syntax--read
/skip-until
(&rest tks
)
191 (while (and (not (memq (car token
) tks
))
192 (not (eq (car token
) 'eob
)))
193 (setq token
(geiser-syntax--read/next-token
)))
196 (defsubst geiser-syntax--read
/try
(&rest tks
)
198 (tk (ignore-errors (apply 'geiser-syntax--read
/match tks
))))
199 (unless tk
(goto-char p
))
202 (defun geiser-syntax--read/list
()
203 (cond ((geiser-syntax--read/try
'dot
)
204 (let ((tail (geiser-syntax--read)))
205 (geiser-syntax--read/skip-until
'eob
'rparen
)
207 ((geiser-syntax--read/try
'rparen
'eob
) nil
)
208 (t (cons (geiser-syntax--read)
209 (geiser-syntax--read/list
)))))
211 (defun geiser-syntax--read ()
212 (let ((token (geiser-syntax--read/next-token
))
213 (max-lisp-eval-depth (max max-lisp-eval-depth
3000)))
216 (lparen (geiser-syntax--read/list
))
217 (vectorb (apply 'vector
(geiser-syntax--read/list
)))
218 ((quote backquote unquote splice
) (list (cdr token
)
219 (geiser-syntax--read)))
220 (kwd (make-symbol (format ":%s" (cdr token
))))
221 (unprintable (format "#<%s>" (cdr token
)))
222 ((char string atom
) (cdr token
))
223 (boolean (cdr token
))
224 (t (error "Reading scheme syntax: unexpected token: %s" token
)))))
226 (defun geiser-syntax--read-from-string (string &optional start end
)
227 (when (stringp string
)
228 (let* ((start (or start
0))
229 (end (or end
(length string
)))
230 (max-lisp-eval-depth (max max-lisp-eval-depth
(- end start
))))
232 (save-excursion (insert string
))
233 (cons (ignore-errors (geiser-syntax--read)) (point))))))
235 (defsubst geiser-syntax--form-after-point
(&optional boundary
)
236 (let ((geiser-syntax--read/buffer-limit
(and (numberp boundary
) boundary
)))
237 (save-excursion (values (geiser-syntax--read) (point)))))
239 (defun geiser-syntax--mapconcat (fun lst sep
)
240 (cond ((null lst
) "")
241 ((not (listp lst
)) (format ".%s%s" sep
(funcall fun lst
)))
242 ((null (cdr lst
)) (format "%s" (funcall fun
(car lst
))))
244 (funcall fun
(car lst
))
246 (geiser-syntax--mapconcat fun
(cdr lst
) sep
)))))
248 (defun geiser-syntax--display (a)
249 (cond ((null a
) "()")
252 ((geiser-syntax--keywordp a
) (format "#%s" a
))
253 ((symbolp a
) (format "%s" a
))
254 ((equal a
"...") "...")
255 ((stringp a
) (format "%S" a
))
256 ((and (listp a
) (symbolp (car a
))
257 (equal (symbol-name (car a
)) "quote"))
258 (format "'%s" (geiser-syntax--display (cadr a
))))
261 (geiser-syntax--mapconcat 'geiser-syntax--display a
" ")))
262 (t (format "%s" a
))))
267 (defsubst geiser-syntax--symbol-at-point
()
268 (and (not (nth 8 (syntax-ppss)))
269 (let ((s (thing-at-point 'symbol
)))
272 (make-symbol (substring-no-properties s
))))))
274 (defsubst geiser-syntax--skip-comment
/string
()
275 (let ((pos (nth 8 (syntax-ppss))))
276 (goto-char (or pos
(point)))
279 (defsubst geiser-syntax--nesting-level
()
280 (or (nth 0 (syntax-ppss)) 0))
282 (defsubst geiser-syntax--pair-length
(p)
283 (if (cdr (last p
)) (1+ (safe-length p
)) (length p
)))
285 (defun geiser-syntax--shallow-form (boundary)
286 (when (looking-at-p "\\s(")
291 (while (< (point) boundary
)
292 (skip-syntax-forward "-<>")
293 (when (<= (point) boundary
)
295 (let ((s (thing-at-point 'symbol
)))
296 (cond ((not s
) (push s elems
))
297 ((not (equal "." s
)) (push (make-symbol s
) elems
)))))))
300 (defsubst geiser-syntax--keywordp
(s)
301 (and s
(symbolp s
) (string-match "^:.+" (symbol-name s
))))
303 (defsubst geiser-syntax--symbol-eq
(s0 s1
)
304 (and (symbolp s0
) (symbolp s1
) (equal (symbol-name s0
) (symbol-name s1
))))
306 (defun geiser-syntax--scan-sexps (&optional begin
)
307 (let* ((fst (geiser-syntax--symbol-at-point))
308 (smth (or fst
(not (looking-at-p "[\s \s)\s>\s<\n]"))))
309 (path (and fst
`((,fst
0)))))
311 (while (not (zerop (geiser-syntax--nesting-level)))
312 (let ((boundary (point)))
313 (geiser-syntax--skip-comment/string
)
315 (let ((form (geiser-syntax--shallow-form boundary
)))
316 (when (and (listp form
) (car form
) (symbolp (car form
)))
317 (let* ((len (geiser-syntax--pair-length form
))
318 (pos (if smth
(1- len
) (progn (setq smth t
) len
)))
319 (prev (and (> pos
1) (nth (1- pos
) form
)))
320 (prev (and (geiser-syntax--keywordp prev
)
322 (push `(,(car form
) ,pos
,@prev
) path
)))))))
323 (mapcar (lambda (e) (cons (format "%S" (car e
)) (cdr e
)))
326 (defsubst geiser-syntax--binding-form-p
(bfs sbfs f
)
328 (let ((f (symbol-name f
)))
329 (or (member f
'("define" "define*" "define-syntax"
330 "syntax-rules" "lambda" "case-lambda"
331 "let" "let*" "let-values" "let*-values"
332 "letrec" "letrec*" "parameterize"))
336 (defsubst geiser-syntax--binding-form
*-p
(sbfs f
)
338 (let ((f (symbol-name f
)))
339 (or (member f
'("let*" "let*-values" "letrec" "letrec*"))
342 (defsubst geiser-syntax--if-symbol
(x) (and (symbolp x
) x
))
343 (defsubst geiser-syntax--if-list
(x) (and (listp x
) x
))
345 (defsubst geiser-syntax--normalize
(vars)
347 (let ((i (if (listp i
) (car i
) i
)))
348 (and (symbolp i
) (symbol-name i
))))
351 (defun geiser-syntax--linearize (form)
352 (cond ((not (listp form
)) (list form
))
354 (t (cons (car form
) (geiser-syntax--linearize (cdr form
))))))
356 (defun geiser-syntax--scan-locals (bfs sbfs form nesting locals
)
357 (if (or (null form
) (not (listp form
)))
358 (geiser-syntax--normalize locals
)
359 (if (not (geiser-syntax--binding-form-p bfs sbfs
(car form
)))
360 (geiser-syntax--scan-locals bfs sbfs
363 (let* ((head (car form
))
364 (name (geiser-syntax--if-symbol (cadr form
)))
365 (names (if name
(geiser-syntax--if-list (caddr form
))
366 (geiser-syntax--if-list (cadr form
))))
368 (geiser-syntax--binding-form-p bfs sbfs
(car names
))))
369 (rest (if (and name
(not bns
)) (cdddr form
) (cddr form
)))
370 (use-names (and (or rest
372 (geiser-syntax--binding-form*-p sbfs head
))
374 (when name
(push name locals
))
375 (when (geiser-syntax--symbol-eq head
'case-lambda
)
376 (dolist (n (and (> nesting
0) (caar (last form
))))
377 (when n
(push n locals
)))
378 (setq rest
(and (> nesting
0) (cdr form
)))
379 (setq use-names nil
))
380 (when (geiser-syntax--symbol-eq head
'syntax-rules
)
381 (dolist (n (and (> nesting
0) (cdaar (last form
))))
382 (when n
(push n locals
)))
383 (setq rest
(and (> nesting
0) (cdr form
))))
385 (dolist (n (geiser-syntax--linearize names
))
386 (let ((xs (if (and (listp n
) (listp (car n
))) (car n
) (list n
))))
387 (dolist (x xs
) (when x
(push x locals
))))))
388 (dolist (f (butlast rest
))
390 (geiser-syntax--symbol-eq (car f
) 'define
)
392 (push (cadr f
) locals
)))
393 (geiser-syntax--scan-locals bfs sbfs
394 (car (last (or rest names
)))
398 (defun geiser-syntax--locals-around-point (bfs sbfs
)
399 (when (eq major-mode
'scheme-mode
)
401 (let ((sym (unless (geiser-syntax--skip-comment/string
)
402 (thing-at-point 'symbol
))))
403 (skip-syntax-forward "->")
404 (let ((boundary (point))
405 (nesting (geiser-syntax--nesting-level)))
406 (while (not (zerop (geiser-syntax--nesting-level)))
408 (multiple-value-bind (form end
)
409 (geiser-syntax--form-after-point boundary
)
411 (geiser-syntax--scan-locals bfs
418 ;;; Fontify strings as Scheme code:
420 (defun geiser-syntax--font-lock-buffer ()
421 (let ((name " *geiser font lock*"))
422 (or (get-buffer name
)
423 (let ((buffer (get-buffer-create name
)))
425 (let ((geiser-default-implementation
426 (or geiser-default-implementation
427 (car geiser-active-implementations
))))
431 (defun geiser-syntax--scheme-str (str)
433 (set-buffer (geiser-syntax--font-lock-buffer))
436 (let ((font-lock-verbose nil
)) (font-lock-fontify-buffer))
440 (provide 'geiser-syntax
)
441 ;;; geiser-syntax.el ends here