1 ;;; cl.el --- Common-Lisp extensions for GNU Emacs Lisp.
3 ;; Copyright (C) 1987, 1988, 1989 Free Software Foundation, Inc.
5 ;; Author: Cesar Quiroz <quiroz@cs.rochester.edu>
6 ;; Keywords: extensions
8 (defvar cl-version
"2.0 beta 29 October 1989")
10 ;; This file is part of GNU Emacs.
12 ;; GNU Emacs is distributed in the hope that it will be useful,
13 ;; but WITHOUT ANY WARRANTY. No author or distributor
14 ;; accepts responsibility to anyone for the consequences of using it
15 ;; or for whether it serves any particular purpose or works at all,
16 ;; unless he says so in writing. Refer to the GNU Emacs General Public
17 ;; License for full details.
19 ;; Everyone is granted permission to copy, modify and redistribute
20 ;; GNU Emacs, but only under the conditions described in the
21 ;; GNU Emacs General Public License. A copy of this license is
22 ;; supposed to have been given to you along with GNU Emacs so you
23 ;; can know your rights and responsibilities. It should be in a
24 ;; file named COPYING. Among other things, the copyright notice
25 ;; and this notice must be preserved on all copies.
29 ;;;; These are extensions to Emacs Lisp that provide some form of
30 ;;;; Common Lisp compatibility, beyond what is already built-in
33 ;;;; When developing them, I had the code spread among several files.
34 ;;;; This file 'cl.el' is a concatenation of those original files,
35 ;;;; minus some declarations that became redundant. The marks between
36 ;;;; the original files can be found easily, as they are lines that
37 ;;;; begin with four semicolons (as this does). The names of the
38 ;;;; original parts follow the four semicolons in uppercase, those
39 ;;;; names are GLOBAL, SYMBOLS, LISTS, SEQUENCES, CONDITIONALS,
40 ;;;; ITERATIONS, MULTIPLE VALUES, ARITH, SETF and DEFSTRUCT. If you
41 ;;;; add functions to this file, you might want to put them in a place
42 ;;;; that is compatible with the division above (or invent your own
45 ;;;; To compile this file, make sure you load it first. This is
46 ;;;; because many things are implemented as macros and now that all
47 ;;;; the files are concatenated together one cannot ensure that
48 ;;;; declaration always precedes use.
52 ;;;; This file provides utilities and declarations that are global
53 ;;;; to Common Lisp and so might be used by more than one of the
54 ;;;; other libraries. Especially, I intend to keep here some
55 ;;;; utilities that help parsing/destructuring some difficult calls.
58 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
59 ;;;; (quiroz@cs.rochester.edu)
61 ;;; Too many pieces of the rest of this package use psetq. So it is unwise to
62 ;;; use here anything but plain Emacs Lisp! There is a neater recursive form
63 ;;; for the algorithm that deals with the bodies.
67 (defmacro psetq
(&rest body
)
68 "(psetq {var value }...) => nil
69 Like setq, but all the values are computed before any assignment is made."
70 (let ((length (length body
)))
71 (cond ((/= (% length
2) 0)
72 (error "psetq needs an even number of arguments, %d given"
79 (bodyforms (reverse body
)))
81 (let* ((value (car bodyforms
))
82 (place (cadr bodyforms
)))
83 (setq bodyforms
(cddr bodyforms
))
85 (setq setqs
(list 'setq place value
))
86 (setq setqs
(list 'setq place
93 ;;; pair-with-newsyms takes a list and returns a list of lists of the
94 ;;; form (newsym form), such that a let* can then bind the evaluation
95 ;;; of the forms to the newsyms. The idea is to guarantee correct
96 ;;; order of evaluation of the subforms of a setf. It also returns a
97 ;;; list of the newsyms generated, in the corresponding order.
99 (defun pair-with-newsyms (oldforms)
100 "PAIR-WITH-NEWSYMS OLDFORMS
101 The top-level components of the list oldforms are paired with fresh
102 symbols, the pairings list and the newsyms list are returned."
103 (do ((ptr oldforms
(cdr ptr
))
106 ((endp ptr
) (values (nreverse bindings
) (nreverse newsyms
)))
107 (let ((newsym (gentemp)))
108 (setq bindings
(cons (list newsym
(car ptr
)) bindings
))
109 (setq newsyms
(cons newsym newsyms
)))))
111 (defun zip-lists (evens odds
)
112 "Merge two lists EVENS and ODDS, taking elts from each list alternatingly.
113 EVENS and ODDS are two lists. ZIP-LISTS constructs a new list, whose
114 even numbered elements (0,2,...) come from EVENS and whose odd numbered
115 elements (1,3,...) come from ODDS.
116 The construction stops when the shorter list is exhausted."
117 (do* ((p0 evens
(cdr p0
))
119 (even (car p0
) (car p0
))
120 (odd (car p1
) (car p1
))
122 ((or (endp p0
) (endp p1
))
125 (cons odd
(cons even result
)))))
127 (defun unzip-list (list)
128 "Extract even and odd elements of LIST into two separate lists.
129 The argument LIST is separated in two strands, the even and the odd
130 numbered elements. Numbering starts with 0, so the first element
131 belongs in EVENS. No check is made that there is an even number of
132 elements to start with."
133 (do* ((ptr list
(cddr ptr
))
134 (this (car ptr
) (car ptr
))
135 (next (cadr ptr
) (cadr ptr
))
139 (values (nreverse evens
) (nreverse odds
)))
140 (setq evens
(cons this evens
))
141 (setq odds
(cons next odds
))))
143 (defun reassemble-argslists (argslists)
144 "(reassemble-argslists ARGSLISTS) => a list of lists
145 ARGSLISTS is a list of sequences. Return a list of lists, the first
146 sublist being all the entries coming from ELT 0 of the original
147 sublists, the next those coming from ELT 1 and so on, until the
148 shortest list is exhausted."
149 (let* ((minlen (apply 'min
(mapcar 'length argslists
)))
151 (dotimes (i minlen
(nreverse result
))
152 ;; capture all the elements at index i
154 (cons (mapcar (function (lambda (sublist) (elt sublist i
)))
159 ;;; Checking that a list of symbols contains no duplicates is a common
160 ;;; task when checking the legality of some macros. The check for 'eq
161 ;;; pairs can be too expensive, as it is quadratic on the length of
162 ;;; the list. I use a 4-pass, linear, counting approach. It surely
163 ;;; loses on small lists (less than 5 elements?), but should win for
164 ;;; larger lists. The fourth pass could be eliminated.
165 ;;; 10 dec 1986. Emacs Lisp has no REMPROP, so I just eliminated the
167 (defun duplicate-symbols-p (list)
168 "Find all symbols appearing more than once in LIST.
169 Return a list of all such duplicates; nil if there are no duplicates."
170 (let ((duplicates '()) ;result built here
171 (propname (gensym)) ;we use a fresh property
174 (unless (and (listp list
)
175 (every 'symbolp list
))
176 (error "a list of symbols is needed"))
182 (put x propname
(1+ (get x propname
))))
185 (if (> (get x propname
) 1)
186 (setq duplicates
(cons x duplicates
))))
187 ;; pass 4: unmark. eliminated.
188 ;; (dolist (x list) (remprop x propname))
192 ;;;; end of cl-global.el
195 ;;;; This file provides the gentemp function, which generates fresh
196 ;;;; symbols, plus some other minor Common Lisp symbol tools.
198 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
199 ;;;; (quiroz@cs.rochester.edu)
201 ;;; Keywords. There are no packages in Emacs Lisp, so this is only a
202 ;;; kludge around to let things be "as if" a keyword package was around.
204 (defmacro defkeyword
(x &optional docstring
)
205 "Make symbol X a keyword (symbol whose value is itself).
206 Optional second arg DOCSTRING is a documentation string for it."
208 (list 'defconst x
(list 'quote x
) docstring
))
210 (error "`%s' is not a symbol" (prin1-to-string x
)))))
212 (defun keywordp (sym)
213 "Return t if SYM is a keyword."
214 (if (and (symbolp sym
) (char-equal (aref (symbol-name sym
) 0) ?\
:))
215 ;; looks like one, make sure value is right
219 (defun keyword-of (sym)
220 "Return a keyword that is naturally associated with symbol SYM.
221 If SYM is keyword, the value is SYM.
222 Otherwise it is a keyword whose name is `:' followed by SYM's name."
223 (cond ((keywordp sym
)
226 (let ((newsym (intern (concat ":" (symbol-name sym
)))))
227 (set newsym newsym
)))
229 (error "expected a symbol, not `%s'" (prin1-to-string sym
)))))
231 ;;; Temporary symbols.
234 (defvar *gentemp-index
* 0
235 "Integer used by `gentemp' to produce new names.")
237 (defvar *gentemp-prefix
* "T$$_"
238 "Names generated by `gentemp begin' with this string by default.")
240 (defun gentemp (&optional prefix oblist
)
241 "Generate a fresh interned symbol.
242 There are two optional arguments, PREFIX and OBLIST. PREFIX is the string
243 that begins the new name, OBLIST is the obarray used to search for old
244 names. The defaults are just right, YOU SHOULD NEVER NEED THESE ARGUMENTS
247 (setq prefix
*gentemp-prefix
*))
249 (setq oblist obarray
)) ;default for the intern functions
250 (let ((newsymbol nil
)
252 (while (not newsymbol
)
253 (setq newname
(concat prefix
*gentemp-index
*))
254 (setq *gentemp-index
* (+ *gentemp-index
* 1))
255 (if (not (intern-soft newname oblist
))
256 (setq newsymbol
(intern newname oblist
))))
259 (defvar *gensym-index
* 0
260 "Integer used by `gensym' to produce new names.")
262 (defvar *gensym-prefix
* "G$$_"
263 "Names generated by `gensym' begin with this string by default.")
265 (defun gensym (&optional prefix
)
266 "Generate a fresh uninterned symbol.
267 Optional arg PREFIX is the string that begins the new name. Most people
268 take just the default, except when debugging needs suggest otherwise."
270 (setq prefix
*gensym-prefix
*))
271 (let ((newsymbol nil
)
273 (while (not newsymbol
)
274 (setq newname
(concat prefix
*gensym-index
*))
275 (setq *gensym-index
* (+ *gensym-index
* 1))
276 (if (not (intern-soft newname
))
277 (setq newsymbol
(make-symbol newname
))))
280 ;;;; end of cl-symbols.el
283 ;;;; This file provides some of the conditional constructs of
284 ;;;; Common Lisp. Total compatibility is again impossible, as the
285 ;;;; 'if' form is different in both languages, so only a good
286 ;;;; approximation is desired.
288 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
289 ;;;; (quiroz@cs.rochester.edu)
292 (put 'case
'lisp-indent-function
1)
293 (put 'ecase
'lisp-indent-function
1)
294 (put 'when
'lisp-indent-function
1)
295 (put 'unless
'lisp-indent-function
1)
298 ;;; These two forms are simplified ifs, with a single branch.
300 (defmacro when
(condition &rest body
)
301 "(when CONDITION . BODY) => evaluate BODY if CONDITION is true."
302 (list* 'if
(list 'not condition
) '() body
))
304 (defmacro unless
(condition &rest body
)
305 "(unless CONDITION . BODY) => evaluate BODY if CONDITION is false."
306 (list* 'if condition
'() body
))
309 ;;; CASE selects among several clauses, based on the value (evaluated)
310 ;;; of a expression and a list of (unevaluated) key values. ECASE is
311 ;;; the same, but signals an error if no clause is activated.
313 (defmacro case
(expr &rest cases
)
314 "(case EXPR . CASES) => evals EXPR, chooses from CASES on that value.
316 CASES -> list of clauses, non empty
317 CLAUSE -> HEAD . BODY
318 HEAD -> t = catch all, must be last clause
319 -> otherwise = same as t
321 -> atom = activated if (eql EXPR HEAD)
322 -> list of atoms = activated if (memq EXPR HEAD)
323 BODY -> list of forms, implicit PROGN is built around it.
324 EXPR is evaluated only once."
325 (let* ((newsym (gentemp))
326 (clauses (case-clausify cases newsym
)))
327 ;; convert case into a cond inside a let
329 (list (list newsym expr
))
330 (list* 'cond
(nreverse clauses
)))))
332 (defmacro ecase
(expr &rest cases
)
333 "(ecase EXPR . CASES) => like `case', but error if no case fits.
334 `t'-clauses are not allowed."
335 (let* ((newsym (gentemp))
336 (clauses (case-clausify cases newsym
)))
337 ;; check that no 't clause is present.
338 ;; case-clausify would put one such at the beginning of clauses
339 (if (eq (caar clauses
) t
)
340 (error "no clause-head should be `t' or `otherwise' for `ecase'"))
341 ;; insert error-catching clause
344 (list 't
(list 'error
345 "ecase on %s = %s failed to take any branch"
347 (list 'prin1-to-string newsym
)))
349 ;; generate code as usual
351 (list (list newsym expr
))
352 (list* 'cond
(nreverse clauses
)))))
355 (defun case-clausify (cases newsym
)
356 "CASE-CLAUSIFY CASES NEWSYM => clauses for a 'cond'
357 Converts the CASES of a [e]case macro into cond clauses to be
358 evaluated inside a let that binds NEWSYM. Returns the clauses in
360 (do* ((currentpos cases
(cdr currentpos
))
361 (nextpos (cdr cases
) (cdr nextpos
))
362 (curclause (car cases
) (car currentpos
))
364 ((endp currentpos
) result
)
365 (let ((head (car curclause
))
366 (body (cdr curclause
)))
367 ;; construct a cond-clause according to the head
369 (error "case clauses cannot have null heads: `%s'"
370 (prin1-to-string curclause
)))
372 (eq head
'otherwise
))
373 ;; check it is the last clause
374 (if (not (endp nextpos
))
375 (error "clause with `t' or `otherwise' head must be last"))
376 ;; accept this clause as a 't' for cond
377 (setq result
(cons (cons 't body
) result
)))
380 (cons (cons (list 'eql newsym
(list 'quote head
)) body
)
384 (cons (cons (list 'memq newsym
(list 'quote head
)) body
)
387 ;; catch-all for this parser
388 (error "don't know how to parse case clause `%s'"
389 (prin1-to-string head
)))))))
391 ;;;; end of cl-conditionals.el
394 ;;;; This file provides simple iterative macros (a la Common Lisp)
395 ;;;; constructed on the basis of let, let* and while, which are the
396 ;;;; primitive binding/iteration constructs of Emacs Lisp
398 ;;;; The Common Lisp iterations use to have a block named nil
399 ;;;; wrapped around them, and allow declarations at the beginning
400 ;;;; of their bodies and you can return a value using (return ...).
401 ;;;; Nothing of the sort exists in Emacs Lisp, so I haven't tried
402 ;;;; to imitate these behaviors.
404 ;;;; Other than the above, the semantics of Common Lisp are
405 ;;;; correctly reproduced to the extent this was reasonable.
407 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
408 ;;;; (quiroz@cs.rochester.edu)
410 ;;; some lisp-indentation information
411 (put 'do
'lisp-indent-function
2)
412 (put 'do
* 'lisp-indent-function
2)
413 (put 'dolist
'lisp-indent-function
1)
414 (put 'dotimes
'lisp-indent-function
1)
415 (put 'do-symbols
'lisp-indent-function
1)
416 (put 'do-all-symbols
'lisp-indent-function
1)
419 (defmacro do
(stepforms endforms
&rest body
)
420 "(do STEPFORMS ENDFORMS . BODY): Iterate BODY, stepping some local
421 variables. STEPFORMS must be a list of symbols or lists. In the second
422 case, the lists must start with a symbol and contain up to two more forms.
423 In the STEPFORMS, a symbol is the same as a (symbol). The other two forms
424 are the initial value (def. NIL) and the form to step (def. itself).
426 The values used by initialization and stepping are computed in parallel.
427 The ENDFORMS are a list (CONDITION . ENDBODY). If the CONDITION evaluates
428 to true in any iteration, ENDBODY is evaluated and the last form in it is
431 The BODY (which may be empty) is evaluated at every iteration, with the
432 symbols of the STEPFORMS bound to the initial or stepped values."
434 ;; check the syntax of the macro
435 (and (check-do-stepforms stepforms
)
436 (check-do-endforms endforms
))
437 ;; construct emacs-lisp equivalent
438 (let ((initlist (extract-do-inits stepforms
))
439 (steplist (extract-do-steps stepforms
))
440 (endcond (car endforms
))
441 (endbody (cdr endforms
)))
442 (cons 'let
(cons initlist
443 (cons (cons 'while
(cons (list 'not endcond
)
444 (append body steplist
)))
445 (append endbody
))))))
448 (defmacro do
* (stepforms endforms
&rest body
)
449 "`do*' is to `do' as `let*' is to `let'.
450 STEPFORMS must be a list of symbols or lists. In the second case, the
451 lists must start with a symbol and contain up to two more forms. In the
452 STEPFORMS, a symbol is the same as a (symbol). The other two forms are
453 the initial value (def. NIL) and the form to step (def. itself).
455 Initializations and steppings are done in the sequence they are written.
457 The ENDFORMS are a list (CONDITION . ENDBODY). If the CONDITION evaluates
458 to true in any iteration, ENDBODY is evaluated and the last form in it is
461 The BODY (which may be empty) is evaluated at every iteration, with
462 the symbols of the STEPFORMS bound to the initial or stepped values."
463 ;; check the syntax of the macro
464 (and (check-do-stepforms stepforms
)
465 (check-do-endforms endforms
))
466 ;; construct emacs-lisp equivalent
467 (let ((initlist (extract-do-inits stepforms
))
468 (steplist (extract-do*-steps stepforms
))
469 (endcond (car endforms
))
470 (endbody (cdr endforms
)))
471 (cons 'let
* (cons initlist
472 (cons (cons 'while
(cons (list 'not endcond
)
473 (append body steplist
)))
474 (append endbody
))))))
477 ;;; DO and DO* share the syntax checking functions that follow.
479 (defun check-do-stepforms (forms)
480 "True if FORMS is a valid stepforms for the do[*] macro (q.v.)"
482 (error "init/step form for do[*] should be a list, not `%s'"
483 (prin1-to-string forms
))
487 (if (not (or (symbolp entry
)
489 (symbolp (car entry
))
490 (< (length entry
) 4))))
491 (error "init/step must be %s, not `%s'"
492 "symbol or (symbol [init [step]])"
493 (prin1-to-string entry
)))))
496 (defun check-do-endforms (forms)
497 "True if FORMS is a valid endforms for the do[*] macro (q.v.)"
499 (error "termination form for do macro should be a list, not `%s'"
500 (prin1-to-string forms
))))
502 (defun extract-do-inits (forms)
503 "Returns a list of the initializations (for do) in FORMS
504 (a stepforms, see the do macro).
505 FORMS is assumed syntactically valid."
509 (cond ((symbolp entry
)
512 (list (car entry
) (cadr entry
))))))
515 ;;; There used to be a reason to deal with DO differently than with
516 ;;; DO*. The writing of PSETQ has made it largely unnecessary.
518 (defun extract-do-steps (forms)
519 "EXTRACT-DO-STEPS FORMS => an s-expr.
520 FORMS is the stepforms part of a DO macro (q.v.). This function constructs
521 an s-expression that does the stepping at the end of an iteration."
522 (list (cons 'psetq
(select-stepping-forms forms
))))
524 (defun extract-do*-steps
(forms)
525 "EXTRACT-DO*-STEPS FORMS => an s-expr.
526 FORMS is the stepforms part of a DO* macro (q.v.). This function constructs
527 an s-expression that does the stepping at the end of an iteration."
528 (list (cons 'setq
(select-stepping-forms forms
))))
530 (defun select-stepping-forms (forms)
531 "Separate only the forms that cause stepping."
532 (let ((result '()) ;ends up being (... var form ...)
533 (ptr forms
) ;to traverse the forms
534 entry
;to explore each form in turn
536 (while ptr
;(not (endp entry)) might be safer
537 (setq entry
(car ptr
))
538 (cond ((and (listp entry
) (= (length entry
) 3))
539 (setq result
(append ;append in reverse order!
540 (list (caddr entry
) (car entry
))
542 (setq ptr
(cdr ptr
))) ;step in the list of forms
545 ;;; Other iterative constructs
547 (defmacro dolist
(stepform &rest body
)
548 "(dolist (VAR LIST [RESULTFORM]) . BODY): do BODY for each elt of LIST.
549 The RESULTFORM defaults to nil. The VAR is bound to successive elements
550 of the value of LIST and remains bound (to the nil value) when the
551 RESULTFORM is evaluated."
555 (error "stepform for `dolist' should be (VAR LIST [RESULT]), not `%s'"
556 (prin1-to-string stepform
)))
557 ((not (symbolp (car stepform
)))
558 (error "first component of stepform should be a symbol, not `%s'"
559 (prin1-to-string (car stepform
))))
560 ((> (length stepform
) 3)
561 (error "too many components in stepform `%s'"
562 (prin1-to-string stepform
))))
564 (let* ((var (car stepform
))
565 (listform (cadr stepform
))
566 (resultform (caddr stepform
)))
570 (cons 'lambda
(cons (list var
) body
)))
573 (list (list var nil
))
576 (defmacro dotimes
(stepform &rest body
)
577 "(dotimes (VAR COUNTFORM [RESULTFORM]) . BODY): Repeat BODY, counting in VAR.
578 The COUNTFORM should return a positive integer. The VAR is bound to
579 successive integers from 0 to COUNTFORM - 1 and the BODY is repeated for
580 each of them. At the end, the RESULTFORM is evaluated and its value
581 returned. During this last evaluation, the VAR is still bound, and its
582 value is the number of times the iteration occurred. An omitted RESULTFORM
587 (error "stepform for `dotimes' should be (VAR COUNT [RESULT]), not `%s'"
588 (prin1-to-string stepform
)))
589 ((not (symbolp (car stepform
)))
590 (error "first component of stepform should be a symbol, not `%s'"
591 (prin1-to-string (car stepform
))))
592 ((> (length stepform
) 3)
593 (error "too many components in stepform `%s'"
594 (prin1-to-string stepform
))))
596 (let* ((var (car stepform
))
597 (countform (cadr stepform
))
598 (resultform (caddr stepform
))
601 'let
* (list (list newsym countform
))
604 (list (list var
0 (list '+ var
1)))
605 (list (list '>= var newsym
) resultform
)
608 (defmacro do-symbols
(stepform &rest body
)
609 "(do_symbols (VAR [OBARRAY [RESULTFORM]]) . BODY)
610 The VAR is bound to each of the symbols in OBARRAY (def. obarray) and
611 the BODY is repeatedly performed for each of those bindings. At the
612 end, RESULTFORM (def. nil) is evaluated and its value returned.
613 During this last evaluation, the VAR is still bound and its value is nil.
614 See also the function `mapatoms'."
618 (error "stepform for `do-symbols' should be (VAR OBARRAY [RESULT]), not `%s'"
619 (prin1-to-string stepform
)))
620 ((not (symbolp (car stepform
)))
621 (error "first component of stepform should be a symbol, not `%s'"
622 (prin1-to-string (car stepform
))))
623 ((> (length stepform
) 3)
624 (error "too many components in stepform `%s'"
625 (prin1-to-string stepform
))))
627 (let* ((var (car stepform
))
628 (oblist (cadr stepform
))
629 (resultform (caddr stepform
)))
633 (cons 'lambda
(cons (list var
) body
)))
636 (list (list var nil
))
640 (defmacro do-all-symbols
(stepform &rest body
)
641 "(do-all-symbols (VAR [RESULTFORM]) . BODY)
642 Is the same as (do-symbols (VAR obarray RESULTFORM) . BODY)."
645 (list (car stepform
) 'obarray
(cadr stepform
))
648 (defmacro loop
(&rest body
)
649 "(loop . BODY) repeats BODY indefinitely and does not return.
650 Normally BODY uses `throw' or `signal' to cause an exit.
651 The forms in BODY should be lists, as non-lists are reserved for new features."
652 ;; check that the body doesn't have atomic forms
654 (error "body of `loop' should be a list of lists or nil")
655 ;; ok, it is a list, check for atomic components
657 (function (lambda (component)
658 (if (nlistp component
)
659 (error "components of `loop' should be lists"))))
661 ;; build the infinite loop
662 (cons 'while
(cons 't body
))))
664 ;;;; end of cl-iterations.el
667 ;;;; This file provides some of the lists machinery of Common-Lisp
668 ;;;; in a way compatible with Emacs Lisp. Especially, see the the
669 ;;;; typical c[ad]*r functions.
671 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
672 ;;;; (quiroz@cs.rochester.edu)
676 ;;; To make these faster, we define them using defsubst. This directs the
677 ;;; compiler to open-code these functions.
679 ;;; Synonyms for list functions
685 "Return the second element of the list LIST."
689 "Return the third element of the list LIST."
693 "Return the fourth element of the list LIST."
697 "Return the fifth element of the list LIST."
701 "Return the sixth element of the list LIST."
704 (defsubst seventh
(x)
705 "Return the seventh element of the list LIST."
709 "Return the eighth element of the list LIST."
713 "Return the ninth element of the list LIST."
717 "Return the tenth element of the list LIST."
725 "t if X is nil, nil if X is a cons; error otherwise."
728 (error "endp received a non-cons, non-null argument `%s'"
729 (prin1-to-string x
))))
732 "Returns the last link in the list LIST."
734 (error "arg to `last' must be a list"))
735 (do ((current-cons x
(cdr current-cons
))
736 (next-cons (cdr x
) (cdr next-cons
)))
737 ((endp next-cons
) current-cons
)))
739 (defun list-length (x) ;taken from CLtL sect. 15.2
740 "Returns the length of a non-circular list, or `nil' for a circular one."
742 (fast x
(cddr fast
)) ;fast pointer, leaps by 2
743 (slow x
(cdr slow
)) ;slow pointer, leaps by 1
744 (ready nil
)) ;indicates termination
747 (setq ready t
)) ;return n
750 (setq ready t
)) ;return n+1
751 ((and (eq fast slow
) (> n
0))
753 (setq ready t
)) ;return nil
755 (setq n
(+ n
2)))))) ;just advance counter
757 (defun butlast (list &optional n
)
758 "Return a new list like LIST but sans the last N elements.
759 N defaults to 1. If the list doesn't have N elements, nil is returned."
760 (if (null n
) (setq n
1))
761 (reverse (nthcdr n
(reverse list
))))
763 (defun list* (arg &rest others
)
764 "Return a new list containing the first arguments consed onto the last arg.
765 Thus, (list* 1 2 3 '(a b)) returns (1 2 3 a b)."
768 (let* ((allargs (cons arg others
))
769 (front (butlast allargs
))
770 (back (last allargs
)))
771 (rplacd (last front
) (car back
))
774 (defun adjoin (item list
)
775 "Return a list which contains ITEM but is otherwise like LIST.
776 If ITEM occurs in LIST, the value is LIST. Otherwise it is (cons ITEM LIST).
777 When comparing ITEM against elements, `eql' is used."
782 (defun ldiff (list sublist
)
783 "Return a new list like LIST but sans SUBLIST.
784 SUBLIST must be one of the links in LIST; otherwise the value is LIST itself."
786 (curcons list
(cdr curcons
)))
787 ((or (endp curcons
) (eq curcons sublist
))
789 (setq result
(cons (car curcons
) result
))))
791 ;;; The popular c[ad]*r functions and other list accessors.
793 ;;; To implement this efficiently, we define them using defsubst,
794 ;;; which directs the compiler to open-code these functions.
797 "Return the car of the car of X."
801 "Return the car of the cdr of X."
805 "Return the cdr of the car of X."
809 "Return the cdr of the cdr of X."
813 "Return the car of the car of the car of X."
817 "Return the car of the car of the cdr of X."
821 "Return the car of the cdr of the car of X."
825 "Return the cdr of the car of the car of X."
829 "Return the car of the cdr of the cdr of X."
833 "Return the cdr of the car of the cdr of X."
837 "Return the cdr of the cdr of the car of X."
841 "Return the cdr of the cdr of the cdr of X."
845 "Return the car of the car of the car of the car of X."
846 (car (car (car (car X
)))))
849 "Return the car of the car of the car of the cdr of X."
850 (car (car (car (cdr X
)))))
853 "Return the car of the car of the cdr of the car of X."
854 (car (car (cdr (car X
)))))
857 "Return the car of the cdr of the car of the car of X."
858 (car (cdr (car (car X
)))))
861 "Return the cdr of the car of the car of the car of X."
862 (cdr (car (car (car X
)))))
865 "Return the car of the car of the cdr of the cdr of X."
866 (car (car (cdr (cdr X
)))))
869 "Return the car of the cdr of the car of the cdr of X."
870 (car (cdr (car (cdr X
)))))
873 "Return the cdr of the car of the car of the cdr of X."
874 (cdr (car (car (cdr X
)))))
877 "Return the car of the cdr of the cdr of the car of X."
878 (car (cdr (cdr (car X
)))))
881 "Return the cdr of the car of the cdr of the car of X."
882 (cdr (car (cdr (car X
)))))
885 "Return the cdr of the cdr of the car of the car of X."
886 (cdr (cdr (car (car X
)))))
889 "Return the car of the cdr of the cdr of the cdr of X."
890 (car (cdr (cdr (cdr X
)))))
893 "Return the cdr of the cdr of the car of the cdr of X."
894 (cdr (cdr (car (cdr X
)))))
897 "Return the cdr of the car of the cdr of the cdr of X."
898 (cdr (car (cdr (cdr X
)))))
901 "Return the cdr of the cdr of the cdr of the car of X."
902 (cdr (cdr (cdr (car X
)))))
905 "Return the cdr of the cdr of the cdr of the cdr of X."
906 (cdr (cdr (cdr (cdr X
)))))
908 ;;; some inverses of the accessors are needed for setf purposes
910 (defun setnth (n list newval
)
911 "Set (nth N LIST) to NEWVAL. Returns NEWVAL."
912 (rplaca (nthcdr n list
) newval
))
914 (defun setnthcdr (n list newval
)
915 "(setnthcdr N LIST NEWVAL) => NEWVAL
916 As a side effect, sets the Nth cdr of LIST to NEWVAL."
918 (error "N must be 0 or greater, not %d" n
))
920 (rplaca list
(car newval
))
921 (rplacd list
(cdr newval
))
924 (rplacd (nthcdr (- n
1) list
) newval
))))
926 ;;; A-lists machinery
928 (defun acons (key item alist
)
929 "Return a new alist with KEY paired with ITEM; otherwise like ALIST.
930 Does not copy ALIST."
931 (cons (cons key item
) alist
))
933 (defun pairlis (keys data
&optional alist
)
934 "Return a new alist with each elt of KEYS paired with an elt of DATA;
935 optional 3rd arg ALIST is nconc'd at the end. KEYS and DATA must
936 have the same length."
937 (unless (= (length keys
) (length data
))
938 (error "keys and data should be the same length"))
939 (do* ;;collect keys and data in front of alist
940 ((kptr keys
(cdr kptr
)) ;traverses the keys
941 (dptr data
(cdr dptr
)) ;traverses the data
942 (key (car kptr
) (car kptr
)) ;current key
943 (item (car dptr
) (car dptr
)) ;current data item
946 (setq result
(acons key item result
))))
950 ;;;; Emacs Lisp provides many of the 'sequences' functionality of
951 ;;;; Common Lisp. This file provides a few things that were left out.
955 (defkeyword :test
"Used to designate positive (selection) tests.")
956 (defkeyword :test-not
"Used to designate negative (rejection) tests.")
957 (defkeyword :key
"Used to designate component extractions.")
958 (defkeyword :predicate
"Used to define matching of sequence components.")
959 (defkeyword :start
"Inclusive low index in sequence")
960 (defkeyword :end
"Exclusive high index in sequence")
961 (defkeyword :start1
"Inclusive low index in first of two sequences.")
962 (defkeyword :start2
"Inclusive low index in second of two sequences.")
963 (defkeyword :end1
"Exclusive high index in first of two sequences.")
964 (defkeyword :end2
"Exclusive high index in second of two sequences.")
965 (defkeyword :count
"Number of elements to affect.")
966 (defkeyword :from-end
"T when counting backwards.")
968 (defun some (pred seq
&rest moreseqs
)
969 "Test PREDICATE on each element of SEQUENCE; is it ever non-nil?
970 Extra args are additional sequences; PREDICATE gets one arg from each
971 sequence and we advance down all the sequences together in lock-step.
972 A sequence means either a list or a vector."
973 (let ((args (reassemble-argslists (list* seq moreseqs
))))
974 (do* ((ready nil
) ;flag: return when t
975 (result nil
) ;resulting value
976 (applyval nil
) ;result of applying pred once
978 (cdr remaining
)) ;remaining argument sets
979 (current (car remaining
) ;current argument set
981 ((or ready
(endp remaining
)) result
)
982 (setq applyval
(apply pred current
))
985 (setq result applyval
)))))
987 (defun every (pred seq
&rest moreseqs
)
988 "Test PREDICATE on each element of SEQUENCE; is it always non-nil?
989 Extra args are additional sequences; PREDICATE gets one arg from each
990 sequence and we advance down all the sequences together in lock-step.
991 A sequence means either a list or a vector."
992 (let ((args (reassemble-argslists (list* seq moreseqs
))))
993 (do* ((ready nil
) ;flag: return when t
994 (result t
) ;resulting value
995 (applyval nil
) ;result of applying pred once
997 (cdr remaining
)) ;remaining argument sets
998 (current (car remaining
) ;current argument set
1000 ((or ready
(endp remaining
)) result
)
1001 (setq applyval
(apply pred current
))
1004 (setq result nil
)))))
1006 (defun notany (pred seq
&rest moreseqs
)
1007 "Test PREDICATE on each element of SEQUENCE; is it always nil?
1008 Extra args are additional sequences; PREDICATE gets one arg from each
1009 sequence and we advance down all the sequences together in lock-step.
1010 A sequence means either a list or a vector."
1011 (let ((args (reassemble-argslists (list* seq moreseqs
))))
1012 (do* ((ready nil
) ;flag: return when t
1013 (result t
) ;resulting value
1014 (applyval nil
) ;result of applying pred once
1016 (cdr remaining
)) ;remaining argument sets
1017 (current (car remaining
) ;current argument set
1019 ((or ready
(endp remaining
)) result
)
1020 (setq applyval
(apply pred current
))
1023 (setq result nil
)))))
1025 (defun notevery (pred seq
&rest moreseqs
)
1026 "Test PREDICATE on each element of SEQUENCE; is it sometimes nil?
1027 Extra args are additional sequences; PREDICATE gets one arg from each
1028 sequence and we advance down all the sequences together in lock-step.
1029 A sequence means either a list or a vector."
1030 (let ((args (reassemble-argslists (list* seq moreseqs
))))
1031 (do* ((ready nil
) ;flag: return when t
1032 (result nil
) ;resulting value
1033 (applyval nil
) ;result of applying pred once
1035 (cdr remaining
)) ;remaining argument sets
1036 (current (car remaining
) ;current argument set
1038 ((or ready
(endp remaining
)) result
)
1039 (setq applyval
(apply pred current
))
1044 ;;; More sequence functions that don't need keyword arguments
1046 (defun concatenate (type &rest sequences
)
1047 "(concatenate TYPE &rest SEQUENCES) => a sequence
1048 The sequence returned is of type TYPE (must be 'list, 'string, or 'vector) and
1049 contains the concatenation of the elements of all the arguments, in the order
1051 (let ((sequences (append sequences
'(()))))
1054 (apply (function append
) sequences
))
1056 (apply (function concat
) sequences
))
1058 (apply (function vector
) (apply (function append
) sequences
)))
1060 (error "type for concatenate `%s' not 'list, 'string or 'vector"
1061 (prin1-to-string type
))))))
1063 (defun map (type function
&rest sequences
)
1064 "(map TYPE FUNCTION &rest SEQUENCES) => a sequence
1065 The FUNCTION is called on each set of elements from the SEQUENCES \(stopping
1066 when the shortest sequence is terminated\) and the results are possibly
1067 returned in a sequence of type TYPE \(one of 'list, 'vector, 'string, or nil\)
1068 giving NIL for TYPE gets rid of the values."
1069 (if (not (memq type
(list 'list
'string
'vector nil
)))
1070 (error "type for map `%s' not 'list, 'string, 'vector or nil"
1071 (prin1-to-string type
)))
1072 (let ((argslists (reassemble-argslists sequences
))
1075 (while argslists
;don't bother accumulating
1076 (apply function
(car argslists
))
1077 (setq argslists
(cdr argslists
)))
1078 (setq results
(mapcar (function (lambda (args) (apply function args
)))
1084 (funcall (function concat
) results
))
1086 (apply (function vector
) results
))))))
1088 ;;; an inverse of elt is needed for setf purposes
1090 (defun setelt (seq n newval
)
1091 "In SEQUENCE, set the Nth element to NEWVAL. Returns NEWVAL.
1092 A sequence means either a list or a vector."
1093 (let ((l (length seq
)))
1094 (if (or (< n
0) (>= n l
))
1095 (error "N(%d) should be between 0 and %d" n l
)
1096 ;; only two cases need be considered valid, as strings are arrays
1098 (setnth n seq newval
))
1100 (aset seq n newval
))
1102 (error "SEQ should be a sequence, not `%s'"
1103 (prin1-to-string seq
)))))))
1105 ;;; Testing with keyword arguments.
1107 ;;; Many of the sequence functions use keywords to denote some stylized
1108 ;;; form of selecting entries in a sequence. The involved arguments
1109 ;;; are collected with a &rest marker (as Emacs Lisp doesn't have a &key
1110 ;;; marker), then they are passed to build-klist, who
1111 ;;; constructs an association list. That association list is used to
1112 ;;; test for satisfaction and matching.
1114 ;;; DON'T USE MEMBER, NOR ANY FUNCTION THAT COULD TAKE KEYWORDS HERE!!!
1116 (defun build-klist (argslist acceptable
&optional allow-other-keys
)
1117 "Decode a keyword argument list ARGSLIST for keywords in ACCEPTABLE.
1118 ARGSLIST is a list, presumably the &rest argument of a call, whose
1119 even numbered elements must be keywords.
1120 ACCEPTABLE is a list of keywords, the only ones that are truly acceptable.
1121 The result is an alist containing the arguments named by the keywords
1122 in ACCEPTABLE, or an error is signalled, if something failed.
1123 If the third argument (an optional) is non-nil, other keys are acceptable."
1124 ;; check legality of the arguments, then destructure them
1125 (unless (and (listp argslist
)
1126 (evenp (length argslist
)))
1127 (error "build-klist: odd number of keyword-args"))
1128 (unless (and (listp acceptable
)
1129 (every 'keywordp acceptable
))
1130 (error "build-klist: second arg should be a list of keywords"))
1131 (multiple-value-bind
1133 (unzip-list argslist
)
1134 (unless (every 'keywordp keywords
)
1135 (error "build-klist: expected keywords, found `%s'"
1136 (prin1-to-string keywords
)))
1137 (unless (or allow-other-keys
1138 (every (function (lambda (keyword)
1139 (memq keyword acceptable
)))
1141 (error "bad keyword[s]: %s not in %s"
1142 (prin1-to-string (mapcan (function (lambda (keyword)
1143 (if (memq keyword acceptable
)
1147 (prin1-to-string acceptable
)))
1148 (do* ;;pick up the pieces
1149 ((auxlist ;auxiliary a-list, may
1150 (pairlis keywords forms
)) ;contain repetitions and junk
1151 (ptr acceptable
(cdr ptr
)) ;pointer in acceptable
1152 (this (car ptr
) (car ptr
)) ;current acceptable keyword
1153 (auxval nil
) ;used to move values around
1154 (alist '())) ;used to build the result
1156 ;; if THIS appears in auxlist, use its value
1157 (when (setq auxval
(assq this auxlist
))
1158 (setq alist
(cons auxval alist
))))))
1161 (defun extract-from-klist (klist key
&optional default
)
1162 "(extract-from-klist KLIST KEY [DEFAULT]) => value of KEY or DEFAULT
1163 Extract value associated with KEY in KLIST (return DEFAULT if nil)."
1164 (let ((retrieved (cdr (assq key klist
))))
1165 (or retrieved default
)))
1167 (defun keyword-argument-supplied-p (klist key
)
1168 "(keyword-argument-supplied-p KLIST KEY) => nil or something
1169 NIL if KEY (a keyword) does not appear in the KLIST."
1172 (defun add-to-klist (key item klist
)
1173 "(ADD-TO-KLIST KEY ITEM KLIST) => new KLIST
1174 Add association (KEY . ITEM) to KLIST."
1175 (setq klist
(acons key item klist
)))
1177 (defun elt-satisfies-test-p (item elt klist
)
1178 "(elt-satisfies-test-p ITEM ELT KLIST) => t or nil
1179 KLIST encodes a keyword-arguments test, as in CH. 14 of CLtL.
1180 True if the given ITEM and ELT satisfy the test."
1181 (let ((test (extract-from-klist klist
:test
))
1182 (test-not (extract-from-klist klist
:test-not
))
1183 (keyfn (extract-from-klist klist
:key
'identity
)))
1185 (funcall test item
(funcall keyfn elt
)))
1187 (not (funcall test-not item
(funcall keyfn elt
))))
1188 (t ;should never happen
1189 (error "neither :test nor :test-not in `%s'"
1190 (prin1-to-string klist
))))))
1192 (defun elt-satisfies-if-p (item klist
)
1193 "(elt-satisfies-if-p ITEM KLIST) => t or nil
1194 True if an -if style function was called and ITEM satisfies the
1195 predicate under :predicate in KLIST."
1196 (let ((predicate (extract-from-klist klist
:predicate
))
1197 (keyfn (extract-from-klist klist
:key
'identity
)))
1198 (funcall predicate item
(funcall keyfn elt
))))
1200 (defun elt-satisfies-if-not-p (item klist
)
1201 "(elt-satisfies-if-not-p ITEM KLIST) => t or nil
1202 KLIST encodes a keyword-arguments test, as in CH. 14 of CLtL.
1203 True if an -if-not style function was called and ITEM does not satisfy
1204 the predicate under :predicate in KLIST."
1205 (let ((predicate (extract-from-klist klist
:predicate
))
1206 (keyfn (extract-from-klist klist
:key
'identity
)))
1207 (not (funcall predicate item
(funcall keyfn elt
)))))
1209 (defun elts-match-under-klist-p (e1 e2 klist
)
1210 "(elts-match-under-klist-p E1 E2 KLIST) => t or nil
1211 KLIST encodes a keyword-arguments test, as in CH. 14 of CLtL.
1212 True if elements E1 and E2 match under the tests encoded in KLIST."
1213 (let ((test (extract-from-klist klist
:test
))
1214 (test-not (extract-from-klist klist
:test-not
))
1215 (keyfn (extract-from-klist klist
:key
'identity
)))
1216 (if (and test test-not
)
1217 (error "both :test and :test-not in `%s'"
1218 (prin1-to-string klist
)))
1220 (funcall test
(funcall keyfn e1
) (funcall keyfn e2
)))
1222 (not (funcall test-not
(funcall keyfn e1
) (funcall keyfn e2
))))
1223 (t ;should never happen
1224 (error "neither :test nor :test-not in `%s'"
1225 (prin1-to-string klist
))))))
1227 ;;; This macro simplifies using keyword args. It is less clumsy than using
1228 ;;; the primitives build-klist, etc... For instance, member could be written
1231 ;;; (defun member (item list &rest kargs)
1232 ;;; (with-keyword-args kargs (test test-not (key 'identity))
1235 ;;; Suggested by Robert Potter (potter@cs.rochester.edu, 15 Nov 1989)
1237 (defmacro with-keyword-args
(keyargslist vardefs
&rest body
)
1238 "(WITH-KEYWORD-ARGS KEYARGSLIST VARDEFS . BODY)
1239 KEYARGSLIST can be either a symbol or a list of one or two symbols.
1240 In the second case, the second symbol is either T or NIL, indicating whether
1241 keywords other than the mentioned ones are tolerable.
1243 VARDEFS is a list. Each entry is either a VAR (symbol) or matches
1244 \(VAR [DEFAULT [KEYWORD]]). Just giving VAR is the same as giving
1247 The BODY is executed in an environment where each VAR (a symbol) is bound to
1248 the value present in the KEYARGSLIST provided, or to the DEFAULT. The value
1249 is searched by using the keyword form of VAR (i.e., :VAR) or the optional
1250 keyword if provided.
1252 Notice that this macro doesn't distinguish between a default value given
1253 explicitly by the user and one provided by default. See also the more
1254 primitive functions build-klist, add-to-klist, extract-from-klist,
1255 keyword-argument-supplied-p, elt-satisfies-test-p, elt-satisfies-if-p,
1256 elt-satisfies-if-not-p, elts-match-under-klist-p. They provide more complete,
1257 if clumsier, control over this feature."
1258 (let (allow-other-keys)
1259 (if (listp keyargslist
)
1260 (if (> (length keyargslist
) 2)
1262 "`%s' should be SYMBOL, (SYMBOL), or (SYMBOL t-OR-nil)"
1263 (prin1-to-string keyargslist
))
1264 (setq allow-other-keys
(cadr keyargslist
)
1265 keyargslist
(car keyargslist
))
1267 (symbolp keyargslist
)
1268 (memq allow-other-keys
'(t nil
))))
1270 "first subform should be SYMBOL, (SYMBOL), or (SYMBOL t-OR-nil)"
1272 (if (symbolp keyargslist
)
1273 (setq allow-other-keys nil
)
1275 "first subform should be SYMBOL, (SYMBOL), or (SYMBOL t-OR-nil)")))
1276 (let (vars defaults keywords forms
1277 (klistname (gensym "KLIST_")))
1278 (mapcar (function (lambda (entry)
1279 (if (symbolp entry
) ;defaulty case
1280 (setq entry
(list entry nil
(keyword-of entry
))))
1281 (let* ((l (length entry
))
1285 (if (or (< l
1) (> l
3))
1287 "`%s' must match (VAR [DEFAULT [KEYWORD]])"
1288 (prin1-to-string entry
)))
1289 (if (or (null v
) (not (symbolp v
)))
1291 "bad variable `%s': must be non-null symbol"
1292 (prin1-to-string v
)))
1293 (setq vars
(cons v vars
))
1294 (setq defaults
(cons d defaults
))
1296 (setq k
(keyword-of v
)))
1299 (not (keywordp k
))))
1301 "bad keyword `%s'" (prin1-to-string k
)))
1302 (setq keywords
(cons k keywords
))
1303 (setq forms
(cons (list v
(list 'extract-from-klist
1310 (list 'let
* (nconc (list (list klistname
1311 (list 'build-klist keyargslist
1312 (list 'quote keywords
)
1316 (put 'with-keyword-args
'lisp-indent-function
1)
1320 ;;; It is here mostly as an example of how to use KLISTs.
1322 ;;; First of all, you need to declare the keywords (done elsewhere in this
1324 ;;; (defkeyword :from-end "syntax of sequence functions")
1325 ;;; (defkeyword :start "syntax of sequence functions")
1328 ;;; Then, you capture all the possible keyword arguments with a &rest
1329 ;;; argument. You can pass that list downward again, of course, but
1330 ;;; internally you need to parse it into a KLIST (an alist, really). One uses
1331 ;;; (build-klist REST-ARGS ACCEPTABLE-KEYWORDS [ALLOW-OTHER]). You can then
1332 ;;; test for presence by using (keyword-argument-supplied-p KLIST KEY) and
1333 ;;; extract a value with (extract-from-klist KLIST KEY [DEFAULT]).
1335 (defun reduce (function sequence
&rest kargs
)
1336 "Apply FUNCTION (a function of two arguments) to succesive pairs of elements
1337 from SEQUENCE. Some keyword arguments are valid after FUNCTION and SEQUENCE:
1338 :from-end If non-nil, process the values backwards
1339 :initial-value If given, prefix it to the SEQUENCE. Suffix, if :from-end
1340 :start Restrict reduction to the subsequence from this index
1341 :end Restrict reduction to the subsequence BEFORE this index.
1342 If the sequence is empty and no :initial-value is given, the FUNCTION is
1343 called on zero (not two) arguments. Otherwise, if there is exactly one
1344 element in the combination of SEQUENCE and the initial value, that element is
1346 (let* ((klist (build-klist kargs
'(:from-end
:start
:end
:initial-value
)))
1347 (length (length sequence
))
1348 (from-end (extract-from-klist klist
:from-end
))
1349 (initial-value-given (keyword-argument-supplied-p
1350 klist
:initial-value
))
1351 (start (extract-from-klist kargs
:start
0))
1352 (end (extract-from-klist kargs
:end length
)))
1353 (setq sequence
(cl$subseq-as-list sequence start end
))
1355 (setq sequence
(reverse sequence
)))
1356 (if initial-value-given
1357 (setq sequence
(cons (extract-from-klist klist
:initial-value
)
1360 (funcall function
) ;only use of 0 arguments
1361 (let* ((result (car sequence
))
1362 (sequence (cdr sequence
)))
1364 (setq result
(if from-end
1365 (funcall function
(car sequence
) result
)
1366 (funcall function result
(car sequence
)))
1367 sequence
(cdr sequence
)))
1370 (defun cl$subseq-as-list
(sequence start end
)
1371 "(cl$subseq-as-list SEQUENCE START END) => a list"
1372 (let ((list (append sequence nil
))
1373 (length (length sequence
))
1376 (error "start should be >= 0, not %d" start
))
1378 (error "end should be <= %d, not %d" length end
))
1379 (if (and (zerop start
) (= end length
))
1382 (vector (apply 'vector list
)))
1384 (setq result
(cons (elt vector i
) result
))
1386 (nreverse result
)))))
1388 ;;;; end of cl-sequences.el
1390 ;;;; Some functions with keyword arguments
1392 ;;;; Both list and sequence functions are considered here together. This
1393 ;;;; doesn't fit any more with the original split of functions in files.
1395 (defun member (item list
&rest kargs
)
1396 "Look for ITEM in LIST; return first tail of LIST the car of whose first
1397 cons cell tests the same as ITEM. Admits arguments :key, :test, and :test-not."
1398 (if (null kargs
) ;treat this fast for efficiency
1400 (let* ((klist (build-klist kargs
'(:test
:test-not
:key
)))
1401 (test (extract-from-klist klist
:test
))
1402 (testnot (extract-from-klist klist
:test-not
))
1403 (key (extract-from-klist klist
:key
'identity
)))
1404 ;; another workaround allegledly for speed
1405 (if (and (or (eq test
'eq
) (eq test
'eql
)
1406 (eq test
(symbol-function 'eq
))
1407 (eq test
(symbol-function 'eql
)))
1409 (or (eq key
'identity
) ;either by default or so given
1410 (eq key
(function identity
)) ;could this happen?
1411 (eq key
(symbol-function 'identity
)) ;sheer paranoia
1414 (if (and test testnot
)
1415 (error ":test and :test-not both specified for member"))
1416 (if (not (or test testnot
))
1418 ;; final hack: remove the indirection through the function names
1420 (if (symbolp testnot
)
1421 (setq testnot
(symbol-function testnot
)))
1423 (setq test
(symbol-function test
))))
1425 (setq key
(symbol-function key
)))
1431 (while (not (or done
(endp ptr
)))
1432 (cond ((not (funcall testnot item
(funcall key
(car ptr
))))
1435 (setq ptr
(cdr ptr
)))
1436 (while (not (or done
(endp ptr
)))
1437 (cond ((funcall test item
(funcall key
(car ptr
)))
1440 (setq ptr
(cdr ptr
))))
1443 ;;;; MULTIPLE VALUES
1444 ;;;; This package approximates the behavior of the multiple-values
1445 ;;;; forms of Common Lisp.
1447 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
1448 ;;;; (quiroz@cs.rochester.edu)
1450 ;;; Lisp indentation information
1451 (put 'multiple-value-bind
'lisp-indent-function
2)
1452 (put 'multiple-value-setq
'lisp-indent-function
2)
1453 (put 'multiple-value-list
'lisp-indent-function nil
)
1454 (put 'multiple-value-call
'lisp-indent-function
1)
1455 (put 'multiple-value-prog1
'lisp-indent-function
1)
1457 ;;; Global state of the package is kept here
1458 (defvar *mvalues-values
* nil
1459 "Most recently returned multiple-values")
1460 (defvar *mvalues-count
* nil
1461 "Count of multiple-values returned, or nil if the mechanism was not used")
1463 ;;; values is the standard multiple-value-return form. Must be the
1464 ;;; last thing evaluated inside a function. If the caller is not
1465 ;;; expecting multiple values, only the first one is passed. (values)
1466 ;;; is the same as no-values returned (unaware callers see nil). The
1467 ;;; alternative (values-list <list>) is just a convenient shorthand
1468 ;;; and complements multiple-value-list.
1470 (defun values (&rest val-forms
)
1471 "Produce multiple values (zero or more). Each arg is one value.
1472 See also `multiple-value-bind', which is one way to examine the
1473 multiple values produced by a form. If the containing form or caller
1474 does not check specially to see multiple values, it will see only
1476 (setq *mvalues-values
* val-forms
)
1477 (setq *mvalues-count
* (length *mvalues-values
*))
1478 (car *mvalues-values
*))
1480 (defun values-list (&optional val-forms
)
1481 "Produce multiple values (zero or mode). Each element of LIST is one value.
1482 This is equivalent to (apply 'values LIST)."
1483 (cond ((nlistp val-forms
)
1484 (error "Argument to values-list must be a list, not `%s'"
1485 (prin1-to-string val-forms
))))
1486 (setq *mvalues-values
* val-forms
)
1487 (setq *mvalues-count
* (length *mvalues-values
*))
1488 (car *mvalues-values
*))
1490 ;;; Callers that want to see the multiple values use these macros.
1492 (defmacro multiple-value-list
(form)
1493 "Execute FORM and return a list of all the (multiple) values FORM produces.
1494 See `values' and `multiple-value-bind'."
1496 (list 'setq
'*mvalues-count
* nil
)
1497 (list 'let
(list (list 'it
'(gensym)))
1498 (list 'set
'it form
)
1499 (list 'if
'*mvalues-count
*
1500 (list 'copy-sequence
'*mvalues-values
*)
1502 (list 'setq
'*mvalues-count
* 1)
1503 (list 'setq
'*mvalues-values
*
1504 (list 'list
(list 'symbol-value
'it
)))
1505 (list 'copy-sequence
'*mvalues-values
*))))))
1507 (defmacro multiple-value-call
(function &rest args
)
1508 "Call FUNCTION on all the values produced by the remaining arguments.
1509 (multiple-value-call '+ (values 1 2) (values 3 4)) is 10."
1510 (let* ((result (gentemp))
1512 (list 'apply
(list 'function
(eval function
))
1513 (list 'let
* (list (list result
'()))
1514 (list 'dolist
(list arg
(list 'quote args
) result
)
1518 (list 'multiple-value-list
1519 (list 'eval arg
)))))))))
1521 (defmacro multiple-value-bind
(vars form
&rest body
)
1522 "Bind VARS to the (multiple) values produced by FORM, then do BODY.
1523 VARS is a list of variables; each is bound to one of FORM's values.
1524 If FORM doesn't make enough values, the extra variables are bound to nil.
1525 (Ordinary forms produce only one value; to produce more, use `values'.)
1526 Extra values are ignored.
1527 BODY (zero or more forms) is executed with the variables bound,
1528 then the bindings are unwound."
1529 (let* ((vals (gentemp)) ;name for intermediate values
1530 (clauses (mv-bind-clausify ;convert into clauses usable
1531 vars vals
))) ; in a let form
1533 (cons (list vals
(list 'multiple-value-list form
))
1537 (defmacro multiple-value-setq
(vars form
)
1538 "Set VARS to the (multiple) values produced by FORM.
1539 VARS is a list of variables; each is set to one of FORM's values.
1540 If FORM doesn't make enough values, the extra variables are set to nil.
1541 (Ordinary forms produce only one value; to produce more, use `values'.)
1542 Extra values are ignored."
1543 (let* ((vals (gentemp)) ;name for intermediate values
1544 (clauses (mv-bind-clausify ;convert into clauses usable
1545 vars vals
))) ; in a setq (after append).
1547 (list (list vals
(list 'multiple-value-list form
)))
1548 (cons 'setq
(apply (function append
) clauses
)))))
1550 (defmacro multiple-value-prog1
(form &rest body
)
1551 "Evaluate FORM, then BODY, then produce the same values FORM produced.
1552 Thus, (multiple-value-prog1 (values 1 2) (foobar)) produces values 1 and 2.
1553 This is like `prog1' except that `prog1' would produce only one value,
1554 which would be the first of FORM's values."
1555 (let* ((heldvalues (gentemp)))
1557 (cons (list (list heldvalues
(list 'multiple-value-list form
)))
1558 (append body
(list (list 'values-list heldvalues
)))))))
1560 ;;; utility functions
1562 ;;; mv-bind-clausify makes the pairs needed to have the variables in
1563 ;;; the variable list correspond with the values returned by the form.
1564 ;;; vals is a fresh symbol that intervenes in all the bindings.
1566 (defun mv-bind-clausify (vars vals
)
1567 "MV-BIND-CLAUSIFY VARS VALS => Auxiliary list
1568 Forms a list of pairs `(,(nth i vars) (nth i vals)) for i from 0 to
1569 the length of VARS (a list of symbols). VALS is just a fresh symbol."
1570 (if (or (nlistp vars
)
1571 (notevery 'symbolp vars
))
1572 (error "expected a list of symbols, not `%s'"
1573 (prin1-to-string vars
)))
1574 (let* ((nvars (length vars
))
1576 (dotimes (n nvars clauses
)
1577 (setq clauses
(cons (list (nth n vars
)
1578 (list 'nth n vals
)) clauses
)))))
1580 ;;;; end of cl-multiple-values.el
1583 ;;;; This file provides integer arithmetic extensions. Although
1584 ;;;; Emacs Lisp doesn't really support anything but integers, that
1585 ;;;; has still to be made to look more or less standard.
1588 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
1589 ;;;; (quiroz@cs.rochester.edu)
1592 (defun plusp (number)
1593 "True if NUMBER is strictly greater than zero."
1596 (defun minusp (number)
1597 "True if NUMBER is strictly less than zero."
1600 (defun oddp (number)
1601 "True if INTEGER is not divisible by 2."
1602 (/= (% number
2) 0))
1604 (defun evenp (number)
1605 "True if INTEGER is divisible by 2."
1609 "Return the absolute value of NUMBER."
1614 (defun signum (number)
1615 "Return -1, 0 or 1 according to the sign of NUMBER."
1623 (defun gcd (&rest integers
)
1624 "Return the greatest common divisor of all the arguments.
1625 The arguments must be integers. With no arguments, value is zero."
1626 (let ((howmany (length integers
)))
1627 (cond ((= howmany
0)
1630 (abs (car integers
)))
1632 (apply (function gcd
)
1633 (cons (gcd (nth 0 integers
) (nth 1 integers
))
1634 (nthcdr 2 integers
))))
1636 ;; essentially the euclidean algorithm
1637 (when (zerop (* (nth 0 integers
) (nth 1 integers
)))
1638 (error "a zero argument is invalid for `gcd'"))
1639 (do* ((absa (abs (nth 0 integers
))) ; better to operate only
1640 (absb (abs (nth 1 integers
))) ;on positives.
1641 (dd (max absa absb
)) ; setup correct order for the
1642 (ds (min absa absb
)) ;succesive divisions.
1643 ;; intermediate results
1647 (done nil
) ; flag: end of iterations
1648 (result 0)) ; final value
1652 (cond ((zerop r
) (setq done t
) (setq result ds
))
1653 (t (setq dd ds
) (setq ds r
))))))))
1655 (defun lcm (integer &rest more
)
1656 "Return the least common multiple of all the arguments.
1657 The arguments must be integers and there must be at least one of them."
1658 (let ((howmany (length more
))
1661 prod
; intermediate product
1662 (yetmore (nthcdr 1 more
)))
1663 (cond ((zerop howmany
)
1665 ((> howmany
1) ; recursive case
1666 (apply (function lcm
)
1667 (cons (lcm a b
) yetmore
)))
1668 (t ; base case, just 2 args
1674 (/ (abs prod
) (gcd a b
))))))))
1676 (defun isqrt (number)
1677 "Return the integer square root of NUMBER.
1678 NUMBER must not be negative. Result is largest integer less than or
1679 equal to the real square root of the argument."
1680 ;; The method used here is essentially the Newtonian iteration
1681 ;; x[n+1] <- (x[n] + Number/x[n]) / 2
1682 ;; suitably adapted to integer arithmetic.
1683 ;; Thanks to Philippe Schnoebelen <phs@lifia.imag.fr> for suggesting the
1684 ;; termination condition.
1685 (cond ((minusp number
)
1686 (error "argument to `isqrt' (%d) must not be negative"
1690 (t ;so (>= number 0)
1691 (do* ((approx 1) ;any positive integer will do
1692 (new 0) ;init value irrelevant
1694 (done (if (> (* approx approx
) number
)
1697 (setq new
(/ (+ approx
(/ number approx
)) 2)
1698 done
(or (= new approx
) (= new
(+ approx
1)))
1701 (defun floor (number &optional divisor
)
1702 "Divide DIVIDEND by DIVISOR, rounding toward minus infinity.
1703 DIVISOR defaults to 1. The remainder is produced as a second value."
1705 ((and (null divisor
) ; trivial case
1708 (t ; do the division
1709 (multiple-value-bind
1711 (safe-idiv number divisor
)
1716 (t ;opposite-signs case
1719 (let ((q (- (+ q
1))))
1720 (values q
(- number
(* q divisor
)))))))))))
1722 (defun ceiling (number &optional divisor
)
1723 "Divide DIVIDEND by DIVISOR, rounding toward plus infinity.
1724 DIVISOR defaults to 1. The remainder is produced as a second value."
1726 ((and (null divisor
) ; trivial case
1729 (t ; do the division
1730 (multiple-value-bind
1732 (safe-idiv number divisor
)
1736 (values (+ q
1) (- r divisor
)))
1738 (values (- q
) (+ number
(* q divisor
)))))))))
1740 (defun truncate (number &optional divisor
)
1741 "Divide DIVIDEND by DIVISOR, rounding toward zero.
1742 DIVISOR defaults to 1. The remainder is produced as a second value."
1744 ((and (null divisor
) ; trivial case
1747 (t ; do the division
1748 (multiple-value-bind
1750 (safe-idiv number divisor
)
1753 ((plusp s
) ;same as floor
1756 (values (- q
) (+ number
(* q divisor
)))))))))
1758 (defun round (number &optional divisor
)
1759 "Divide DIVIDEND by DIVISOR, rounding to nearest integer.
1760 DIVISOR defaults to 1. The remainder is produced as a second value."
1761 (cond ((and (null divisor
) ; trivial case
1764 (t ; do the division
1765 (multiple-value-bind
1767 (safe-idiv number divisor
)
1769 ;; adjust magnitudes first, and then signs
1770 (let ((other-r (- (abs divisor
) r
)))
1771 (cond ((> r other-r
)
1775 ;; round to even is mandatory
1778 (setq r
(- number
(* q divisor
)))
1781 (defun mod (number divisor
)
1782 "Return remainder of X by Y (rounding quotient toward minus infinity).
1783 That is, the remainder goes with the quotient produced by `floor'."
1784 (multiple-value-bind (q r
) (floor number divisor
)
1787 (defun rem (number divisor
)
1788 "Return remainder of X by Y (rounding quotient toward zero).
1789 That is, the remainder goes with the quotient produced by `truncate'."
1790 (multiple-value-bind (q r
) (truncate number divisor
)
1793 ;;; internal utilities
1795 ;;; safe-idiv performs an integer division with positive numbers only.
1796 ;;; It is known that some machines/compilers implement weird remainder
1797 ;;; computations when working with negatives, so the idea here is to
1798 ;;; make sure we know what is coming back to the caller in all cases.
1800 ;;; Signum computation fixed by mad@math.keio.JUNET (MAEDA Atusi)
1802 (defun safe-idiv (a b
)
1803 "SAFE-IDIV A B => Q R S
1804 Q=|A|/|B|, R is the rest, S is the sign of A/B."
1805 (unless (and (numberp a
) (numberp b
))
1806 (error "arguments to `safe-idiv' must be numbers"))
1808 (error "cannot divide %d by zero" a
))
1809 (let* ((absa (abs a
))
1812 (s (* (signum a
) (signum b
)))
1813 (r (- a
(* (* s q
) b
))))
1816 ;;;; end of cl-arith.el
1819 ;;;; This file provides the setf macro and friends. The purpose has
1820 ;;;; been modest, only the simplest defsetf forms are accepted.
1821 ;;;; Use it and enjoy.
1823 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
1824 ;;;; (quiroz@cs.rochester.edu)
1827 (defkeyword :setf-update-fn
1828 "Property, its value is the function setf must invoke to update a
1829 generalized variable whose access form is a function call of the
1830 symbol that has this property.")
1832 (defkeyword :setf-update-doc
1833 "Property of symbols that have a `defsetf' update function on them,
1834 installed by the `defsetf' from its optional third argument.")
1836 (defmacro setf
(&rest pairs
)
1837 "Generalized `setq' that can set things other than variable values.
1838 A use of `setf' looks like (setf {PLACE VALUE}...).
1839 The behavior of (setf PLACE VALUE) is to access the generalized variable
1840 at PLACE and store VALUE there. It returns VALUE. If there is more
1841 than one PLACE and VALUE, each PLACE is set from its VALUE before
1842 the next PLACE is evaluated."
1843 (let ((nforms (length pairs
)))
1844 ;; check the number of subforms
1845 (cond ((/= (% nforms
2) 0)
1846 (error "odd number of arguments to `setf'"))
1850 ;; this is the recursive case
1852 (do* ;collect the place-value pairs
1853 ((args pairs
(cddr args
))
1854 (place (car args
) (car args
))
1855 (value (cadr args
) (cadr args
))
1857 ((endp args
) (nreverse result
))
1859 (cons (list 'setf place value
)
1862 ;; this is the base case (SETF PLACE VALUE)
1863 (let* ((place (car pairs
))
1864 (value (cadr pairs
))
1867 ;; dispatch on the type of the PLACE
1868 (cond ((symbolp place
)
1869 (list 'setq place value
))
1871 (setq head
(car place
))
1873 (setq updatefn
(get head
:setf-update-fn
)))
1874 (if (or (and (consp updatefn
) (eq (car updatefn
) 'lambda
))
1875 (and (symbolp updatefn
)
1877 (let ((defn (symbol-function updatefn
)))
1880 (eq (car defn
) 'lambda
))))))
1881 (cons updatefn
(append (cdr place
) (list value
)))
1882 (multiple-value-bind
1884 (pair-with-newsyms (append (cdr place
) (list value
)))
1885 ;; this let gets new symbols to ensure adequate
1886 ;; order of evaluation of the subforms.
1889 (cons updatefn newsyms
)))))
1891 (error "no `setf' update-function for `%s'"
1892 (prin1-to-string place
)))))))))
1894 (defmacro defsetf
(accessfn updatefn
&optional docstring
)
1895 "Define how `setf' works on a certain kind of generalized variable.
1896 A use of `defsetf' looks like (defsetf ACCESSFN UPDATEFN [DOCSTRING]).
1897 ACCESSFN is a symbol. UPDATEFN is a function or macro which takes
1898 one more argument than ACCESSFN does. DEFSETF defines the translation
1899 of (SETF (ACCESFN . ARGS) NEWVAL) to be a form like (UPDATEFN ARGS... NEWVAL).
1900 The function UPDATEFN must return its last arg, after performing the
1901 updating called for."
1902 ;; reject ill-formed requests. too bad one can't test for functionp
1904 (when (not (symbolp accessfn
))
1905 (error "first argument of `defsetf' must be a symbol, not `%s'"
1906 (prin1-to-string accessfn
)))
1907 ;; update properties
1909 (list 'put
(list 'quote accessfn
)
1910 :setf-update-fn
(list 'function updatefn
))
1911 (list 'put
(list 'quote accessfn
) :setf-update-doc docstring
)
1912 ;; any better thing to return?
1913 (list 'quote accessfn
)))
1915 ;;; This section provides the "default" setfs for Common-Emacs-Lisp
1916 ;;; The user will not normally add anything to this, although
1917 ;;; defstruct will introduce new ones as a matter of fact.
1919 ;;; Apply is a special case. The Common Lisp
1920 ;;; standard makes the case of apply be useful when the user writes
1921 ;;; something like (apply #'name ...), Emacs Lisp doesn't have the #
1922 ;;; stuff, but it has (function ...). Notice that V18 includes a new
1923 ;;; apply: this file is compatible with V18 and pre-V18 Emacses.
1925 ;;; INCOMPATIBILITY: the SETF macro evaluates its arguments in the
1926 ;;; (correct) left to right sequence *before* checking for apply
1927 ;;; methods (which should really be an special case inside setf). Due
1928 ;;; to this, the lambda expression defsetf'd to apply will succeed in
1929 ;;; applying the right function even if the name was not quoted, but
1930 ;;; computed! That extension is not Common Lisp (nor is particularly
1931 ;;; useful, I think).
1934 (lambda (&rest args
)
1935 ;; dissasemble the calling form
1936 ;; "(((quote fn) x1 x2 ... xn) val)" (function instead of quote, too)
1937 (let* ((fnform (car args
)) ;functional form
1938 (applyargs (append ;arguments "to apply fnform"
1939 (apply 'list
* (butlast (cdr args
)))
1941 (newupdater nil
)) ; its update-fn, if any
1942 (if (and (symbolp fnform
)
1943 (setq newupdater
(get fnform
:setf-update-fn
)))
1944 (apply newupdater applyargs
)
1945 (error "can't `setf' to `%s'"
1946 (prin1-to-string fnform
)))))
1947 "`apply' is a special case for `setf'")
1952 "`setf' inversion for `aref'")
1956 "`setf' inversion for `nth'")
1960 "`setf' inversion for `nthcdr'")
1964 "`setf' inversion for `elt'")
1967 (lambda (list val
) (setnth 0 list val
))
1968 "`setf' inversion for `first'")
1971 (lambda (list val
) (setnth 1 list val
))
1972 "`setf' inversion for `second'")
1975 (lambda (list val
) (setnth 2 list val
))
1976 "`setf' inversion for `third'")
1979 (lambda (list val
) (setnth 3 list val
))
1980 "`setf' inversion for `fourth'")
1983 (lambda (list val
) (setnth 4 list val
))
1984 "`setf' inversion for `fifth'")
1987 (lambda (list val
) (setnth 5 list val
))
1988 "`setf' inversion for `sixth'")
1991 (lambda (list val
) (setnth 6 list val
))
1992 "`setf' inversion for `seventh'")
1995 (lambda (list val
) (setnth 7 list val
))
1996 "`setf' inversion for `eighth'")
1999 (lambda (list val
) (setnth 8 list val
))
2000 "`setf' inversion for `ninth'")
2003 (lambda (list val
) (setnth 9 list val
))
2004 "`setf' inversion for `tenth'")
2007 (lambda (list val
) (setcdr list val
))
2008 "`setf' inversion for `rest'")
2010 (defsetf car setcar
"Replace the car of a cons")
2012 (defsetf cdr setcdr
"Replace the cdr of a cons")
2015 (lambda (list val
) (setcar (nth 0 list
) val
))
2016 "`setf' inversion for `caar'")
2019 (lambda (list val
) (setcar (cdr list
) val
))
2020 "`setf' inversion for `cadr'")
2023 (lambda (list val
) (setcdr (car list
) val
))
2024 "`setf' inversion for `cdar'")
2027 (lambda (list val
) (setcdr (cdr list
) val
))
2028 "`setf' inversion for `cddr'")
2031 (lambda (list val
) (setcar (caar list
) val
))
2032 "`setf' inversion for `caaar'")
2035 (lambda (list val
) (setcar (cadr list
) val
))
2036 "`setf' inversion for `caadr'")
2039 (lambda (list val
) (setcar (cdar list
) val
))
2040 "`setf' inversion for `cadar'")
2043 (lambda (list val
) (setcdr (caar list
) val
))
2044 "`setf' inversion for `cdaar'")
2047 (lambda (list val
) (setcar (cddr list
) val
))
2048 "`setf' inversion for `caddr'")
2051 (lambda (list val
) (setcdr (cadr list
) val
))
2052 "`setf' inversion for `cdadr'")
2055 (lambda (list val
) (setcdr (cdar list
) val
))
2056 "`setf' inversion for `cddar'")
2059 (lambda (list val
) (setcdr (cddr list
) val
))
2060 "`setf' inversion for `cdddr'")
2063 (lambda (list val
) (setcar (caaar list
) val
))
2064 "`setf' inversion for `caaaar'")
2067 (lambda (list val
) (setcar (caadr list
) val
))
2068 "`setf' inversion for `caaadr'")
2071 (lambda (list val
) (setcar (cadar list
) val
))
2072 "`setf' inversion for `caadar'")
2075 (lambda (list val
) (setcar (cdaar list
) val
))
2076 "`setf' inversion for `cadaar'")
2079 (lambda (list val
) (setcdr (caar list
) val
))
2080 "`setf' inversion for `cdaaar'")
2083 (lambda (list val
) (setcar (caddr list
) val
))
2084 "`setf' inversion for `caaddr'")
2087 (lambda (list val
) (setcar (cdadr list
) val
))
2088 "`setf' inversion for `cadadr'")
2091 (lambda (list val
) (setcdr (caadr list
) val
))
2092 "`setf' inversion for `cdaadr'")
2095 (lambda (list val
) (setcar (cddar list
) val
))
2096 "`setf' inversion for `caddar'")
2099 (lambda (list val
) (setcdr (cadar list
) val
))
2100 "`setf' inversion for `cdadar'")
2103 (lambda (list val
) (setcdr (cdaar list
) val
))
2104 "`setf' inversion for `cddaar'")
2107 (lambda (list val
) (setcar (cdddr list
) val
))
2108 "`setf' inversion for `cadddr'")
2111 (lambda (list val
) (setcdr (cdadr list
) val
))
2112 "`setf' inversion for `cddadr'")
2115 (lambda (list val
) (setcdr (caddr list
) val
))
2116 "`setf' inversion for `cdaddr'")
2119 (lambda (list val
) (setcdr (cddar list
) val
))
2120 "`setf' inversion for `cdddar'")
2123 (lambda (list val
) (setcdr (cddr list
) val
))
2124 "`setf' inversion for `cddddr'")
2126 (defsetf get put
"`setf' inversion for `get' is `put'")
2128 (defsetf symbol-function fset
2129 "`setf' inversion for `symbol-function' is `fset'")
2131 (defsetf symbol-plist setplist
2132 "`setf' inversion for `symbol-plist' is `setplist'")
2134 (defsetf symbol-value set
2135 "`setf' inversion for `symbol-value' is `set'")
2137 (defsetf point goto-char
2138 "To set (point) to N, use (goto-char N)")
2140 ;; how about defsetfing other Emacs forms?
2144 ;;; It could be nice to implement define-modify-macro, but I don't
2145 ;;; think it really pays.
2147 (defmacro incf
(ref &optional delta
)
2148 "(incf REF [DELTA]) -> increment the g.v. REF by DELTA (default 1)"
2151 (list 'setf ref
(list '+ ref delta
)))
2153 (defmacro decf
(ref &optional delta
)
2154 "(decf REF [DELTA]) -> decrement the g.v. REF by DELTA (default 1)"
2157 (list 'setf ref
(list '- ref delta
)))
2159 (defmacro push
(item ref
)
2160 "(push ITEM REF) -> cons ITEM at the head of the g.v. REF (a list)"
2161 (list 'setf ref
(list 'cons item ref
)))
2163 (defmacro pushnew
(item ref
)
2164 "(pushnew ITEM REF): adjoin ITEM at the head of the g.v. REF (a list)"
2165 (list 'setf ref
(list 'adjoin item ref
)))
2168 "(pop REF) -> (prog1 (car REF) (setf REF (cdr REF)))"
2169 (let ((listname (gensym)))
2170 (list 'let
(list (list listname ref
))
2172 (list 'car listname
)
2173 (list 'setf ref
(list 'cdr listname
))))))
2177 ;;; Psetf is the generalized variable equivalent of psetq. The right
2178 ;;; hand sides are evaluated and assigned (via setf) to the left hand
2179 ;;; sides. The evaluations are done in an environment where they
2180 ;;; appear to occur in parallel.
2182 (defmacro psetf
(&rest body
)
2183 "(psetf {var value }...) => nil
2184 Like setf, but all the values are computed before any assignment is made."
2185 (let ((length (length body
)))
2186 (cond ((/= (% length
2) 0)
2187 (error "psetf needs an even number of arguments, %d given"
2194 (bodyforms (reverse body
)))
2196 (let* ((value (car bodyforms
))
2197 (place (cadr bodyforms
)))
2198 (setq bodyforms
(cddr bodyforms
))
2200 (setq setfs
(list 'setf place value
))
2201 (setq setfs
(list 'setf place
2206 ;;; SHIFTF and ROTATEF
2209 (defmacro shiftf
(&rest forms
)
2210 "(shiftf PLACE1 PLACE2... NEWVALUE)
2211 Set PLACE1 to PLACE2, PLACE2 to PLACE3...
2212 Each PLACE is set to the old value of the following PLACE,
2213 and the last PLACE is set to the value NEWVALUE.
2214 Returns the old value of PLACE1."
2215 (unless (> (length forms
) 1)
2216 (error "`shiftf' needs more than one argument"))
2217 (let ((places (butlast forms
))
2218 (newvalue (car (last forms
))))
2219 ;; the places are accessed to fresh symbols
2220 (multiple-value-bind
2222 (pair-with-newsyms places
)
2226 (append (cdr newsyms
) (list newvalue
))))
2229 (defmacro rotatef
(&rest places
)
2230 "(rotatef PLACE...) sets each PLACE to the old value of the following PLACE.
2231 The last PLACE is set to the old value of the first PLACE.
2232 Thus, the values rotate through the PLACEs. Returns nil."
2235 (multiple-value-bind
2237 (pair-with-newsyms places
)
2242 (append (cdr newsyms
) (list (car newsyms
)))))
2246 ;;;; This file provides the structures mechanism. See the
2247 ;;;; documentation for Common-Lisp's defstruct. Mine doesn't
2248 ;;;; implement all the functionality of the standard, although some
2249 ;;;; more could be grafted if so desired. More details along with
2253 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
2254 ;;;; (quiroz@cs.rochester.edu)
2257 (defkeyword :include
"Syntax of `defstruct'")
2258 (defkeyword :named
"Syntax of `defstruct'")
2259 (defkeyword :conc-name
"Syntax of `defstruct'")
2260 (defkeyword :copier
"Syntax of `defstruct'")
2261 (defkeyword :predicate
"Syntax of `defstruct'")
2262 (defkeyword :print-function
"Syntax of `defstruct'")
2263 (defkeyword :type
"Syntax of `defstruct'")
2264 (defkeyword :initial-offset
"Syntax of `defstruct'")
2266 (defkeyword :structure-doc
"Documentation string for a structure.")
2267 (defkeyword :structure-slotsn
"Number of slots in structure")
2268 (defkeyword :structure-slots
"List of the slot's names")
2269 (defkeyword :structure-indices
"List of (KEYWORD-NAME . INDEX)")
2270 (defkeyword :structure-initforms
"List of (KEYWORD-NAME . INITFORM)")
2271 (defkeyword :structure-includes
2272 "() or list of a symbol, that this struct includes")
2273 (defkeyword :structure-included-in
2274 "List of the structs that include this")
2277 (defmacro defstruct
(&rest args
)
2278 "(defstruct NAME [DOC-STRING] . SLOTS) define NAME as structure type.
2279 NAME must be a symbol, the name of the new structure. It could also
2280 be a list (NAME . OPTIONS).
2282 Each option is either a symbol, or a list of a keyword symbol taken from the
2283 list \{:conc-name, :copier, :constructor, :predicate, :include,
2284 :print-function, :type, :initial-offset\}. The meanings of these are as in
2285 CLtL, except that no BOA-constructors are provided, and the options
2286 \{:print-fuction, :type, :initial-offset\} are ignored quietly. All these
2287 structs are named, in the sense that their names can be used for type
2290 The DOC-STRING is established as the `structure-doc' property of NAME.
2292 The SLOTS are one or more of the following:
2293 SYMBOL -- meaning the SYMBOL is the name of a SLOT of NAME
2294 list of SYMBOL and VALUE -- meaning that VALUE is the initial value of
2296 `defstruct' defines functions `make-NAME', `NAME-p', `copy-NAME' for the
2297 structure, and functions with the same name as the slots to access
2298 them. `setf' of the accessors sets their values."
2299 (multiple-value-bind
2300 (name options docstring slotsn slots initlist
)
2301 (parse$defstruct$args args
)
2302 ;; Names for the member functions come from the options. The
2303 ;; slots* stuff collects info about the slots declared explicitly.
2304 (multiple-value-bind
2305 (conc-name constructor copier predicate
2306 moreslotsn moreslots moreinits included
)
2307 (parse$defstruct$options name options slots
)
2308 ;; The moreslots* stuff refers to slots gained as a consequence
2309 ;; of (:include clauses). -- Oct 89: Only one :include tolerated
2310 (when (and (numberp moreslotsn
)
2312 (setf slotsn
(+ slotsn moreslotsn
))
2313 (setf slots
(append moreslots slots
))
2314 (setf initlist
(append moreinits initlist
)))
2315 (unless (> slotsn
0)
2316 (error "%s needs at least one slot"
2317 (prin1-to-string name
)))
2318 (let ((dups (duplicate-symbols-p slots
)))
2320 (error "`%s' are duplicates"
2321 (prin1-to-string dups
))))
2322 (setq initlist
(simplify$inits slots initlist
))
2323 (let (properties functions keywords accessors alterators returned
)
2324 ;; compute properties of NAME
2328 (list 'put
(list 'quote name
) :structure-doc
2330 (list 'put
(list 'quote name
) :structure-slotsn
2332 (list 'put
(list 'quote name
) :structure-slots
2333 (list 'quote slots
))
2334 (list 'put
(list 'quote name
) :structure-initforms
2335 (list 'quote initlist
))
2336 (list 'put
(list 'quote name
) :structure-indices
2337 (list 'quote
(extract$indices initlist
))))
2338 ;; If this definition :includes another defstruct,
2339 ;; modify both property lists.
2345 (list 'quote included
))
2348 (list 'get
(list 'quote
(car included
))
2349 :structure-included-in
))))
2352 (let ((old (gensym)))
2358 :structure-includes
))))
2362 :structure-included-in
2365 ;; careful with destructive
2372 :structure-included-in
)
2379 ;; If this definition used to be :included in another, warn
2380 ;; that things make break. On the other hand, the redefinition
2381 ;; may be trivial, so don't call it an error.
2382 (let ((old (gensym)))
2385 (list (list old
(list 'get
2387 :structure-included-in
)))
2390 "`%s' redefined. Should redefine `%s'?"
2392 (list 'prin1-to-string old
))))))))
2394 ;; Compute functions associated with NAME. This is not
2395 ;; handling BOA constructors yet, but here would be the place.
2398 (list 'fset
(list 'quote constructor
)
2400 (list 'lambda
(list '&rest
'args
)
2401 (list 'make$structure$instance
2404 (list 'fset
(list 'quote copier
)
2406 (list 'lambda
(list 'struct
)
2407 (list 'copy-sequence
'struct
))))
2408 (let ((typetag (gensym)))
2409 (list 'fset
(list 'quote predicate
)
2413 'lambda
(list 'thing
)
2415 (list 'vectorp
'thing
)
2418 (list 'elt
'thing
0)))
2426 (list 'length
'thing
)
2433 :structure-included-in
))))))
2435 ;; compute accessors for NAME's slots
2436 (multiple-value-setq
2437 (accessors alterators keywords
)
2438 (build$accessors$for name conc-name predicate slots slotsn
))
2439 ;; generate returned value -- not defined by the standard
2444 '(lambda (x) (list 'quote x
))
2445 (cons name slots
)))))
2448 (nconc properties functions keywords
2449 accessors alterators returned
))))))
2451 (defun parse$defstruct$args
(args)
2452 "(parse$defstruct$args ARGS) => NAME OPTIONS DOCSTRING SLOTSN SLOTS INITLIST
2453 NAME=symbol, OPTIONS=list of, DOCSTRING=string, SLOTSN=count of slots,
2454 SLOTS=list of their names, INITLIST=alist (keyword . initform)."
2455 (let (name ;args=(symbol...) or ((symbol...)...)
2456 options
;args=((symbol . options) ...)
2457 (docstring "") ;args=(head docstring . slotargs)
2458 slotargs
;second or third cdr of args
2459 (slotsn 0) ;number of slots
2460 (slots '()) ;list of slot names
2461 (initlist '())) ;list of (slot keyword . initform)
2462 ;; extract name and options
2463 (cond ((symbolp (car args
)) ;simple name
2464 (setq name
(car args
)
2466 ((and (listp (car args
)) ;(name . options)
2467 (symbolp (caar args
)))
2468 (setq name
(caar args
)
2469 options
(cdar args
)))
2471 (error "first arg to `defstruct' must be symbol or (symbol ...)")))
2472 (setq slotargs
(cdr args
))
2473 ;; is there a docstring?
2474 (when (stringp (car slotargs
))
2475 (setq docstring
(car slotargs
)
2476 slotargs
(cdr slotargs
)))
2477 ;; now for the slots
2478 (multiple-value-bind
2479 (slotsn slots initlist
)
2480 (process$slots slotargs
)
2481 (values name options docstring slotsn slots initlist
))))
2483 (defun process$slots
(slots)
2484 "(process$slots SLOTS) => SLOTSN SLOTSLIST INITLIST
2485 Converts a list of symbols or lists of symbol and form into the last 3
2486 values returned by PARSE$DEFSTRUCT$ARGS."
2487 (let ((slotsn (length slots
)) ;number of slots
2488 slotslist
;(slot1 slot2 ...)
2489 initlist
) ;((:slot1 . init1) ...)
2491 ((ptr slots
(cdr ptr
))
2492 (this (car ptr
) (car ptr
)))
2494 (cond ((symbolp this
)
2495 (setq slotslist
(cons this slotslist
))
2496 (setq initlist
(acons (keyword-of this
) nil initlist
)))
2498 (symbolp (car this
)))
2499 (let ((name (car this
))
2501 ;; this silently ignores any slot options. bad...
2502 (setq slotslist
(cons name slotslist
))
2503 (setq initlist
(acons (keyword-of name
) form initlist
))))
2505 (error "slot should be symbol or (symbol ...), not `%s'"
2506 (prin1-to-string this
)))))
2507 (values slotsn
(nreverse slotslist
) (nreverse initlist
))))
2509 (defun parse$defstruct$options
(name options slots
)
2510 "(parse$defstruct$options name OPTIONS SLOTS) => many values
2511 A defstruct named NAME, with options list OPTIONS, has already slots SLOTS.
2512 Parse the OPTIONS and return the updated form of the struct's slots and other
2513 information. The values returned are:
2515 CONC-NAME is the string to use as prefix/suffix in the methods,
2516 CONST is the name of the official constructor,
2517 COPIER is the name of the structure copier,
2518 PRED is the name of the type predicate,
2519 MORESLOTSN is the number of slots added by :include,
2520 MORESLOTS is the list of slots added by :include,
2521 MOREINITS is the list of initialization forms added by :include,
2522 INCLUDED is nil, or the list of the symbol added by :include"
2523 (let* ((namestring (symbol-name name
))
2524 ;; to build the return values
2525 (conc-name (concat namestring
"-"))
2526 (const (intern (concat "make-" namestring
)))
2527 (copier (intern (concat "copy-" namestring
)))
2528 (pred (intern (concat namestring
"-p")))
2533 option-head
;When an option is not a plain
2534 option-second
; keyword, it must be a list of
2535 option-rest
; the form (head second . rest)
2536 these-slotsn
;When :include is found, the
2537 these-slots
; info about the included
2538 these-inits
; structure is added here.
2539 included
;NIL or (list INCLUDED)
2541 ;; Values above are the defaults. Now we read the options themselves
2542 (dolist (option options
)
2543 ;; 2 cases arise, as options must be a keyword or a list
2550 (error "can't recognize option `%s'"
2551 (prin1-to-string option
)))))
2552 ((and (listp option
)
2553 (keywordp (setq option-head
(car option
))))
2554 (setq option-second
(second option
))
2555 (setq option-rest
(nthcdr 2 option
))
2560 ((stringp option-second
)
2562 ((null option-second
)
2565 (error "`%s' is invalid as `conc-name'"
2566 (prin1-to-string option-second
))))))
2570 ((and (symbolp option-second
)
2574 (error "can't recognize option `%s'"
2575 (prin1-to-string option
))))))
2577 (:constructor
;no BOA-constructors allowed
2580 ((and (symbolp option-second
)
2584 (error "can't recognize option `%s'"
2585 (prin1-to-string option
))))))
2589 ((and (symbolp option-second
)
2593 (error "can't recognize option `%s'"
2594 (prin1-to-string option
))))))
2596 (unless (symbolp option-second
)
2597 (error "arg to `:include' should be a symbol, not `%s'"
2598 (prin1-to-string option-second
)))
2599 (setq these-slotsn
(get option-second
:structure-slotsn
)
2600 these-slots
(get option-second
:structure-slots
)
2601 these-inits
(get option-second
:structure-initforms
))
2602 (unless (and (numberp these-slotsn
)
2604 (error "`%s' is not a valid structure"
2605 (prin1-to-string option-second
)))
2607 (error "`%s' already includes `%s', can't include `%s' too"
2608 name
(car included
) option-second
)
2609 (push option-second included
))
2610 (multiple-value-bind
2611 (xtra-slotsn xtra-slots xtra-inits
)
2612 (process$slots option-rest
)
2613 (when (> xtra-slotsn
0)
2614 (dolist (xslot xtra-slots
)
2615 (unless (memq xslot these-slots
)
2616 (error "`%s' is not a slot of `%s'"
2617 (prin1-to-string xslot
)
2618 (prin1-to-string option-second
))))
2619 (setq these-inits
(append xtra-inits these-inits
)))
2620 (setq moreslotsn
(+ moreslotsn these-slotsn
))
2621 (setq moreslots
(append these-slots moreslots
))
2622 (setq moreinits
(append these-inits moreinits
))))
2623 ((:print-function
:type
:initial-offset
)
2626 (error "can't recognize option `%s'"
2627 (prin1-to-string option
)))))
2629 (error "can't recognize option `%s'"
2630 (prin1-to-string option
)))))
2631 ;; Return values found
2632 (values conc-name const copier pred
2633 moreslotsn moreslots moreinits
2636 (defun simplify$inits
(slots initlist
)
2637 "(simplify$inits SLOTS INITLIST) => new INITLIST
2638 Removes from INITLIST - an ALIST - any shadowed bindings."
2639 (let ((result '()) ;built here
2642 (dolist (slot slots
)
2643 (setq key
(keyword-of slot
))
2644 (setq result
(acons key
(cdr (assoc key initlist
)) result
)))
2647 (defun extract$indices
(initlist)
2648 "(extract$indices INITLIST) => indices list
2649 Kludge. From a list of pairs (keyword . form) build a list of pairs
2650 of the form (keyword . position in list from 0). Useful to precompute
2651 some of the work of MAKE$STRUCTURE$INSTANCE."
2654 (dolist (entry initlist
(nreverse result
))
2655 (setq result
(acons (car entry
) index result
)
2656 index
(+ index
1)))))
2658 (defun build$accessors$for
(name conc-name predicate slots slotsn
)
2659 "(build$accessors$for NAME PREDICATE SLOTS SLOTSN) => FSETS DEFSETFS KWDS
2660 Generate the code for accesors and defsetfs of a structure called
2661 NAME, whose slots are SLOTS. Also, establishes the keywords for the
2667 (canonic "")) ;slot name with conc-name prepended
2670 (nreverse accessors
) (nreverse alterators
) (nreverse keywords
)))
2671 (setq canonic
(intern (concat conc-name
(symbol-name (nth i slots
)))))
2674 (list 'fset
(list 'quote canonic
)
2676 (list 'lambda
(list 'object
)
2678 (list (list predicate
'object
)
2679 (list 'aref
'object
(1+ i
)))
2682 "`%s' is not a struct %s"
2683 (list 'prin1-to-string
2685 (list 'prin1-to-string
2691 (list 'defsetf canonic
2692 (list 'lambda
(list 'object
'newval
)
2694 (list (list predicate
'object
)
2695 (list 'aset
'object
(1+ i
) 'newval
))
2699 (list 'prin1-to-string
2701 (list 'prin1-to-string
2706 (cons (list 'defkeyword
(keyword-of (nth i slots
)))
2709 (defun make$structure$instance
(name args
)
2710 "(make$structure$instance NAME ARGS) => new struct NAME
2711 A struct of type NAME is created, some slots might be initialized
2712 according to ARGS (the &rest argument of MAKE-name)."
2713 (unless (symbolp name
)
2714 (error "`%s' is not a possible name for a structure"
2715 (prin1-to-string name
)))
2716 (let ((initforms (get name
:structure-initforms
))
2717 (slotsn (get name
:structure-slotsn
))
2718 (indices (get name
:structure-indices
))
2719 initalist
;pairlis'd on initforms
2720 initializers
;definitive initializers
2722 ;; check sanity of the request
2723 (unless (and (numberp slotsn
)
2725 (error "`%s' is not a defined structure"
2726 (prin1-to-string name
)))
2727 (unless (evenp (length args
))
2728 (error "slot initializers `%s' not of even length"
2729 (prin1-to-string args
)))
2730 ;; analyze the initializers provided by the call
2731 (multiple-value-bind
2732 (speckwds specvals
) ;keywords and values given
2733 (unzip-list args
) ; by the user
2734 ;; check that all the arguments are introduced by keywords
2735 (unless (every (function keywordp
) speckwds
)
2736 (error "all of the names in `%s' should be keywords"
2737 (prin1-to-string speckwds
)))
2738 ;; check that all the keywords are known
2739 (dolist (kwd speckwds
)
2740 (unless (numberp (cdr (assoc kwd indices
)))
2741 (error "`%s' is not a valid slot name for %s"
2742 (prin1-to-string kwd
) (prin1-to-string name
))))
2746 (do* ;;protect values from further evaluation
2747 ((ptr specvals
(cdr ptr
))
2748 (val (car ptr
) (car ptr
))
2750 ((endp ptr
) (nreverse result
))
2752 (cons (list 'quote val
)
2754 (copy-sequence initforms
)))
2755 ;; compute definitive initializers
2757 (do* ;;gather the values of the most definitive forms
2758 ((ptr indices
(cdr ptr
))
2759 (key (caar ptr
) (caar ptr
))
2761 ((endp ptr
) (nreverse result
))
2763 (cons (eval (cdr (assoc key initalist
))) result
))))
2764 ;; do real initialization
2765 (apply (function vector
)
2766 (cons name initializers
)))))
2768 ;;;; end of cl-structs.el
2770 ;;; For lisp-interaction mode, so that multiple values can be seen when passed
2771 ;;; back. Lies every now and then...
2773 (defvar - nil
"form currently under evaluation")
2774 (defvar + nil
"previous -")
2775 (defvar ++ nil
"previous +")
2776 (defvar +++ nil
"previous ++")
2777 (defvar / nil
"list of values returned by +")
2778 (defvar // nil
"list of values returned by ++")
2779 (defvar /// nil
"list of values returned by +++")
2780 (defvar * nil
"(first) value of +")
2781 (defvar ** nil
"(first) value of ++")
2782 (defvar *** nil
"(first) value of +++")
2784 (defun cl-eval-print-last-sexp ()
2785 "Evaluate sexp before point; print value\(s\) into current buffer.
2786 If the evaled form returns multiple values, they are shown one to a line.
2787 The variables -, +, ++, +++, *, **, ***, /, //, /// have their usual meaning.
2789 It clears the multiple-value passing mechanism, and does not pass back
2790 multiple values. Use this only if you are debugging cl.el and understand well
2791 how the multiple-value stuff works, because it can be fooled into believing
2792 that multiple values have been returned when they actually haven't, for
2794 \(identity \(values nil 1\)\)
2795 However, even when this fails, you can trust the first printed value to be
2796 \(one of\) the returned value\(s\)."
2798 ;; top level call, can reset mvalues
2799 (setq *mvalues-count
* nil
2800 *mvalues-values
* nil
)
2801 (setq -
(car (read-from-string
2803 (let ((stab (syntax-table)))
2806 (set-syntax-table emacs-lisp-mode-syntax-table
)
2809 (set-syntax-table stab
)))
2820 (cond ((or (null *mvalues-count
*) ;mvalues mechanism not used
2821 (not (eq * (car *mvalues-values
*))))
2822 (print * (current-buffer)))
2823 ((null /) ;no values returned
2824 (terpri (current-buffer)))
2825 (t ;more than zero mvalues
2826 (terpri (current-buffer))
2827 (mapcar (function (lambda (value)
2828 (prin1 value
(current-buffer))
2829 (terpri (current-buffer))))
2831 (setq *mvalues-count
* nil
;make sure
2832 *mvalues-values
* nil
))
2834 ;;;; More LISTS functions
2837 ;;; Some mapping functions on lists, commonly useful.
2838 ;;; They take no extra sequences, to go along with Emacs Lisp's MAPCAR.
2840 (defun mapc (function list
)
2841 "(MAPC FUNCTION LIST) => LIST
2842 Apply FUNCTION to each element of LIST, return LIST.
2843 Like mapcar, but called only for effect."
2846 (funcall function
(car args
))
2847 (setq args
(cdr args
))))
2850 (defun maplist (function list
)
2851 "(MAPLIST FUNCTION LIST) => list'ed results of FUNCTION on cdrs of LIST
2852 Apply FUNCTION to successive sublists of LIST, return the list of the results"
2856 (setq results
(cons (funcall function args
) results
)
2858 (nreverse results
)))
2860 (defun mapl (function list
)
2861 "(MAPL FUNCTION LIST) => LIST
2862 Apply FUNCTION to successive cdrs of LIST, return LIST.
2863 Like maplist, but called only for effect."
2866 (funcall function args
)
2867 (setq args
(cdr args
)))
2870 (defun mapcan (function list
)
2871 "(MAPCAN FUNCTION LIST) => nconc'd results of FUNCTION on LIST
2872 Apply FUNCTION to each element of LIST, nconc the results.
2873 Beware: nconc destroys its first argument! See copy-list."
2877 (setq results
(nconc (funcall function
(car args
)) results
)
2879 (nreverse results
)))
2881 (defun mapcon (function list
)
2882 "(MAPCON FUNCTION LIST) => nconc'd results of FUNCTION on cdrs of LIST
2883 Apply FUNCTION to successive sublists of LIST, nconc the results.
2884 Beware: nconc destroys its first argument! See copy-list."
2888 (setq results
(nconc (funcall function args
) results
)
2890 (nreverse results
)))
2894 (defun copy-list (list)
2895 "Build a copy of LIST"
2898 (defun copy-tree (tree)
2899 "Build a copy of the tree of conses TREE
2900 The argument is a tree of conses, it is recursively copied down to
2901 non conses. Circularity and sharing of substructure are not
2902 necessarily preserved."
2904 (cons (copy-tree (car tree
))
2905 (copy-tree (cdr tree
)))
2908 ;;; reversals, and destructive manipulations of a list's spine
2910 (defun revappend (x y
)
2911 "does what (append (reverse X) Y) would, only faster"
2914 (revappend (cdr x
) (cons (car x
) y
))))
2916 (defun nreconc (x y
)
2917 "does (nconc (nreverse X) Y) would, only faster
2918 Destructive on X, be careful."
2921 ;; reuse the first cons of x, making it point to y
2922 (nreconc (cdr x
) (prog1 x
(rplacd x y
)))))
2924 (defun nbutlast (list &optional n
)
2925 "Side-effected LIST truncated N+1 conses from the end.
2926 This is the destructive version of BUTLAST. Returns () and does not
2927 modify the LIST argument if the length of the list is not at least N."
2928 (when (null n
) (setf n
1))
2929 (let ((length (list-length list
)))
2930 (cond ((null length
)
2935 (setnthcdr (- length n
) list nil
)
2940 (defun subst (new old tree
)
2941 "NEW replaces OLD in a copy of TREE
2942 Uses eql for the test."
2943 (subst-if new
(function (lambda (x) (eql x old
))) tree
))
2945 (defun subst-if-not (new test tree
)
2946 "NEW replaces any subtree or leaf that fails TEST in a copy of TREE"
2947 ;; (subst-if new (function (lambda (x) (not (funcall test x)))) tree)
2948 (cond ((not (funcall test tree
))
2953 (let ((head (subst-if-not new test
(car tree
)))
2954 (tail (subst-if-not new test
(cdr tree
))))
2955 ;; If nothing changed, return originals. Else use the new
2956 ;; components to assemble a new tree.
2957 (if (and (eql head
(car tree
))
2958 (eql tail
(cdr tree
)))
2960 (cons head tail
))))))
2962 (defun subst-if (new test tree
)
2963 "NEW replaces any subtree or leaf that satisfies TEST in a copy of TREE"
2964 (cond ((funcall test tree
)
2969 (let ((head (subst-if new test
(car tree
)))
2970 (tail (subst-if new test
(cdr tree
))))
2971 ;; If nothing changed, return originals. Else use the new
2972 ;; components to assemble a new tree.
2973 (if (and (eql head
(car tree
))
2974 (eql tail
(cdr tree
)))
2976 (cons head tail
))))))
2978 (defun sublis (alist tree
)
2979 "Use association list ALIST to modify a copy of TREE
2980 If a subtree or leaf of TREE is a key in ALIST, it is replaced by the
2981 associated value. Not exactly Common Lisp, but close in spirit and
2982 compatible with the native Emacs Lisp ASSOC, which uses EQUAL."
2983 (let ((toplevel (assoc tree alist
)))
2984 (cond (toplevel ;Bingo at top
2986 ((atom tree
) ;Give up on this
2989 (let ((head (sublis alist
(car tree
)))
2990 (tail (sublis alist
(cdr tree
))))
2991 (if (and (eql head
(car tree
))
2992 (eql tail
(cdr tree
)))
2994 (cons head tail
)))))))
2996 (defun member-if (predicate list
)
2997 "PREDICATE is applied to the members of LIST. As soon as one of them
2998 returns true, that tail of the list if returned. Else NIL."
2999 (catch 'found-member-if
3000 (while (not (endp list
))
3001 (if (funcall predicate
(car list
))
3002 (throw 'found-member-if list
)
3003 (setq list
(cdr list
))))
3006 (defun member-if-not (predicate list
)
3007 "PREDICATE is applied to the members of LIST. As soon as one of them
3008 returns false, that tail of the list if returned. Else NIL."
3009 (catch 'found-member-if-not
3010 (while (not (endp list
))
3011 (if (funcall predicate
(car list
))
3012 (setq list
(cdr list
))
3013 (throw 'found-member-if-not list
)))
3016 (defun tailp (sublist list
)
3017 "(tailp SUBLIST LIST) => True if SUBLIST is a sublist of LIST."
3019 (while (not (endp list
))
3020 (if (eq sublist list
)
3021 (throw 'tailp-found t
)
3022 (setq list
(cdr list
))))
3025 ;;; Suggestion of phr%widow.Berkeley.EDU@lilac.berkeley.edu
3027 (defmacro declare
(&rest decls
)
3028 "Ignore a Common-Lisp declaration."
3029 "declarations are ignored in this implementation")
3031 (defun proclaim (&rest decls
)
3032 "Ignore a Common-Lisp proclamation."
3033 "declarations are ignored in this implementation")
3035 (defmacro the
(type form
)
3036 "(the TYPE FORM) macroexpands to FORM
3037 No checking is even attempted. This is just for compatibility with