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1 ;;; cl.el --- Common-Lisp extensions for GNU Emacs Lisp.
3 ;; Author: Cesar Quiroz <quiroz@cs.rochester.edu>
4 ;; Last-Modified: 16 Mar 1992
5 ;; Keywords: extensions
9 ;; Copyright (C) 1987, 1988, 1989 Free Software Foundation, Inc.
11 ;; This file is part of GNU Emacs.
13 ;; GNU Emacs is distributed in the hope that it will be useful,
14 ;; but WITHOUT ANY WARRANTY. No author or distributor
15 ;; accepts responsibility to anyone for the consequences of using it
16 ;; or for whether it serves any particular purpose or works at all,
17 ;; unless he says so in writing. Refer to the GNU Emacs General Public
18 ;; License for full details.
20 ;; Everyone is granted permission to copy, modify and redistribute
21 ;; GNU Emacs, but only under the conditions described in the
22 ;; GNU Emacs General Public License. A copy of this license is
23 ;; supposed to have been given to you along with GNU Emacs so you
24 ;; can know your rights and responsibilities. It should be in a
25 ;; file named COPYING. Among other things, the copyright notice
26 ;; and this notice must be preserved on all copies.
28 ;;; Commentary:
30 ;;;; These are extensions to Emacs Lisp that provide some form of
31 ;;;; Common Lisp compatibility, beyond what is already built-in
32 ;;;; in Emacs Lisp.
33 ;;;;
34 ;;;; When developing them, I had the code spread among several files.
35 ;;;; This file 'cl.el' is a concatenation of those original files,
36 ;;;; minus some declarations that became redundant. The marks between
37 ;;;; the original files can be found easily, as they are lines that
38 ;;;; begin with four semicolons (as this does). The names of the
39 ;;;; original parts follow the four semicolons in uppercase, those
40 ;;;; names are GLOBAL, SYMBOLS, LISTS, SEQUENCES, CONDITIONALS,
41 ;;;; ITERATIONS, MULTIPLE VALUES, ARITH, SETF and DEFSTRUCT. If you
42 ;;;; add functions to this file, you might want to put them in a place
43 ;;;; that is compatible with the division above (or invent your own
44 ;;;; categories).
45 ;;;;
46 ;;;; To compile this file, make sure you load it first. This is
47 ;;;; because many things are implemented as macros and now that all
48 ;;;; the files are concatenated together one cannot ensure that
49 ;;;; declaration always precedes use.
50 ;;;;
51 \f
52 ;;;; GLOBAL
53 ;;;; This file provides utilities and declarations that are global
54 ;;;; to Common Lisp and so might be used by more than one of the
55 ;;;; other libraries. Especially, I intend to keep here some
56 ;;;; utilities that help parsing/destructuring some difficult calls.
57 ;;;;
58 ;;;;
59 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
60 ;;;; (quiroz@cs.rochester.edu)
62 ;;; Too many pieces of the rest of this package use psetq. So it is unwise to
63 ;;; use here anything but plain Emacs Lisp! There is a neater recursive form
64 ;;; for the algorithm that deals with the bodies.
66 ;;; Code:
69 "(psetq {var value }...) => nil
70 Like setq, but all the values are computed before any assignment is made."
74 length))
76 '())
89 setqs))))))
90 setqs))))))
91 \f
92 ;;; utilities
93 ;;;
94 ;;; pair-with-newsyms takes a list and returns a list of lists of the
95 ;;; form (newsym form), such that a let* can then bind the evaluation
96 ;;; of the forms to the newsyms. The idea is to guarantee correct
97 ;;; order of evaluation of the subforms of a setf. It also returns a
98 ;;; list of the newsyms generated, in the corresponding order.
101 "PAIR-WITH-NEWSYMS OLDFORMS
102 The top-level components of the list oldforms are paired with fresh
103 symbols, the pairings list and the newsyms list are returned."
113 "Merge two lists EVENS and ODDS, taking elts from each list alternatingly.
114 EVENS and ODDS are two lists. ZIP-LISTS constructs a new list, whose
115 even numbered elements (0,2,...) come from EVENS and whose odd numbered
116 elements (1,3,...) come from ODDS.
117 The construction stops when the shorter list is exhausted."
129 "Extract even and odd elements of LIST into two separate lists.
130 The argument LIST is separated in two strands, the even and the odd
131 numbered elements. Numbering starts with 0, so the first element
132 belongs in EVENS. No check is made that there is an even number of
133 elements to start with."
143 \f
145 "(reassemble-argslists ARGSLISTS) => a list of lists
146 ARGSLISTS is a list of sequences. Return a list of lists, the first
147 sublist being all the entries coming from ELT 0 of the original
148 sublists, the next those coming from ELT 1 and so on, until the
149 shortest list is exhausted."
153 ;; capture all the elements at index i
156 argslists)
157 result)))))
159 \f
160 ;;; Checking that a list of symbols contains no duplicates is a common
161 ;;; task when checking the legality of some macros. The check for 'eq
162 ;;; pairs can be too expensive, as it is quadratic on the length of
163 ;;; the list. I use a 4-pass, linear, counting approach. It surely
164 ;;; loses on small lists (less than 5 elements?), but should win for
165 ;;; larger lists. The fourth pass could be eliminated.
166 ;;; 10 dec 1986. Emacs Lisp has no REMPROP, so I just eliminated the
167 ;;; 4th pass.
169 "Find all symbols appearing more than once in LIST.
170 Return a list of all such duplicates; nil if there are no duplicates."
173 )
174 ;; check validity
178 ;; pass 1: mark
181 ;; pass 2: count
184 ;; pass 3: collect
188 ;; pass 4: unmark. eliminated.
189 ;; (dolist (x list) (remprop x propname))
190 ;; return result
191 duplicates))
193 ;;;; end of cl-global.el
194 \f
195 ;;;; SYMBOLS
196 ;;;; This file provides the gentemp function, which generates fresh
197 ;;;; symbols, plus some other minor Common Lisp symbol tools.
198 ;;;;
199 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
200 ;;;; (quiroz@cs.rochester.edu)
202 ;;; Keywords. There are no packages in Emacs Lisp, so this is only a
203 ;;; kludge around to let things be "as if" a keyword package was around.
206 "Make symbol X a keyword (symbol whose value is itself).
207 Optional second arg DOCSTRING is a documentation string for it."
214 "Return t if SYM is a keyword."
216 ;; looks like one, make sure value is right
218 nil))
221 "Return a keyword that is naturally associated with symbol SYM.
222 If SYM is keyword, the value is SYM.
223 Otherwise it is a keyword whose name is `:' followed by SYM's name."
225 sym)
231 \f
232 ;;; Temporary symbols.
233 ;;;
242 "Generate a fresh interned symbol.
243 There are two optional arguments, PREFIX and OBLIST. PREFIX is the string
244 that begins the new name, OBLIST is the obarray used to search for old
245 names. The defaults are just right, YOU SHOULD NEVER NEED THESE ARGUMENTS
246 IN YOUR OWN CODE."
258 newsymbol))
259 \f
267 "Generate a fresh uninterned symbol.
268 Optional arg PREFIX is the string that begins the new name. Most people
269 take just the default, except when debugging needs suggest otherwise."
279 newsymbol))
281 ;;;; end of cl-symbols.el
282 \f
283 ;;;; CONDITIONALS
284 ;;;; This file provides some of the conditional constructs of
285 ;;;; Common Lisp. Total compatibility is again impossible, as the
286 ;;;; 'if' form is different in both languages, so only a good
287 ;;;; approximation is desired.
288 ;;;;
289 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
290 ;;;; (quiroz@cs.rochester.edu)
292 ;;; indentation info
298 ;;; WHEN and UNLESS
299 ;;; These two forms are simplified ifs, with a single branch.
302 "(when CONDITION . BODY) => evaluate BODY if CONDITION is true."
306 "(unless CONDITION . BODY) => evaluate BODY if CONDITION is false."
308 \f
309 ;;; CASE and ECASE
310 ;;; CASE selects among several clauses, based on the value (evaluated)
311 ;;; of a expression and a list of (unevaluated) key values. ECASE is
312 ;;; the same, but signals an error if no clause is activated.
315 "(case EXPR . CASES) => evals EXPR, chooses from CASES on that value.
316 EXPR -> any form
317 CASES -> list of clauses, non empty
318 CLAUSE -> HEAD . BODY
319 HEAD -> t = catch all, must be last clause
320 -> otherwise = same as t
321 -> nil = illegal
322 -> atom = activated if (eql EXPR HEAD)
323 -> list of atoms = activated if (memq EXPR HEAD)
324 BODY -> list of forms, implicit PROGN is built around it.
325 EXPR is evaluated only once."
328 ;; convert case into a cond inside a let
334 "(ecase EXPR . CASES) => like `case', but error if no case fits.
335 `t'-clauses are not allowed."
338 ;; check that no 't clause is present.
339 ;; case-clausify would put one such at the beginning of clauses
342 ;; insert error-catching clause
346 "ecase on %s = %s failed to take any branch"
349 clauses))
350 ;; generate code as usual
355 \f
357 "CASE-CLAUSIFY CASES NEWSYM => clauses for a 'cond'
358 Converts the CASES of a [e]case macro into cond clauses to be
359 evaluated inside a let that binds NEWSYM. Returns the clauses in
360 reverse order."
368 ;; construct a cond-clause according to the head
374 ;; check it is the last clause
377 ;; accept this clause as a 't' for cond
382 result)))
386 result)))
388 ;; catch-all for this parser
392 ;;;; end of cl-conditionals.el
393 \f
394 ;;;; ITERATIONS
395 ;;;; This file provides simple iterative macros (a la Common Lisp)
396 ;;;; constructed on the basis of let, let* and while, which are the
397 ;;;; primitive binding/iteration constructs of Emacs Lisp
398 ;;;;
399 ;;;; The Common Lisp iterations use to have a block named nil
400 ;;;; wrapped around them, and allow declarations at the beginning
401 ;;;; of their bodies and you can return a value using (return ...).
402 ;;;; Nothing of the sort exists in Emacs Lisp, so I haven't tried
403 ;;;; to imitate these behaviors.
404 ;;;;
405 ;;;; Other than the above, the semantics of Common Lisp are
406 ;;;; correctly reproduced to the extent this was reasonable.
407 ;;;;
408 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
409 ;;;; (quiroz@cs.rochester.edu)
411 ;;; some lisp-indentation information
419 \f
421 "(do STEPFORMS ENDFORMS . BODY): Iterate BODY, stepping some local
422 variables. STEPFORMS must be a list of symbols or lists. In the second
423 case, the lists must start with a symbol and contain up to two more forms.
424 In the STEPFORMS, a symbol is the same as a (symbol). The other two forms
425 are the initial value (def. NIL) and the form to step (def. itself).
427 The values used by initialization and stepping are computed in parallel.
428 The ENDFORMS are a list (CONDITION . ENDBODY). If the CONDITION evaluates
429 to true in any iteration, ENDBODY is evaluated and the last form in it is
430 returned.
432 The BODY (which may be empty) is evaluated at every iteration, with the
433 symbols of the STEPFORMS bound to the initial or stepped values."
435 ;; check the syntax of the macro
438 ;; construct emacs-lisp equivalent
448 \f
450 "`do*' is to `do' as `let*' is to `let'.
451 STEPFORMS must be a list of symbols or lists. In the second case, the
452 lists must start with a symbol and contain up to two more forms. In the
453 STEPFORMS, a symbol is the same as a (symbol). The other two forms are
454 the initial value (def. NIL) and the form to step (def. itself).
456 Initializations and steppings are done in the sequence they are written.
458 The ENDFORMS are a list (CONDITION . ENDBODY). If the CONDITION evaluates
459 to true in any iteration, ENDBODY is evaluated and the last form in it is
460 returned.
462 The BODY (which may be empty) is evaluated at every iteration, with
463 the symbols of the STEPFORMS bound to the initial or stepped values."
464 ;; check the syntax of the macro
467 ;; construct emacs-lisp equivalent
477 \f
478 ;;; DO and DO* share the syntax checking functions that follow.
481 "True if FORMS is a valid stepforms for the do[*] macro (q.v.)"
493 "symbol or (symbol [init [step]])"
495 forms)))
498 "True if FORMS is a valid endforms for the do[*] macro (q.v.)"
504 "Returns a list of the initializations (for do) in FORMS
505 (a stepforms, see the do macro).
506 FORMS is assumed syntactically valid."
514 forms))
516 ;;; There used to be a reason to deal with DO differently than with
517 ;;; DO*. The writing of PSETQ has made it largely unnecessary.
520 "EXTRACT-DO-STEPS FORMS => an s-expr.
521 FORMS is the stepforms part of a DO macro (q.v.). This function constructs
522 an s-expression that does the stepping at the end of an iteration."
526 "EXTRACT-DO*-STEPS FORMS => an s-expr.
527 FORMS is the stepforms part of a DO* macro (q.v.). This function constructs
528 an s-expression that does the stepping at the end of an iteration."
532 "Separate only the forms that cause stepping."
535 entry ;to explore each form in turn
536 )
542 result))))
545 \f
546 ;;; Other iterative constructs
549 "(dolist (VAR LIST [RESULTFORM]) . BODY): do BODY for each elt of LIST.
550 The RESULTFORM defaults to nil. The VAR is bound to successive elements
551 of the value of LIST and remains bound (to the nil value) when the
552 RESULTFORM is evaluated."
553 ;; check sanity
564 ;; generate code
572 listform)
575 resultform))))
578 "(dotimes (VAR COUNTFORM [RESULTFORM]) . BODY): Repeat BODY, counting in VAR.
579 The COUNTFORM should return a positive integer. The VAR is bound to
580 successive integers from 0 to COUNTFORM - 1 and the BODY is repeated for
581 each of them. At the end, the RESULTFORM is evaluated and its value
582 returned. During this last evaluation, the VAR is still bound, and its
583 value is the number of times the iteration occurred. An omitted RESULTFORM
584 defaults to nil."
585 ;; check sanity
596 ;; generate code
607 body))))
608 \f
610 "(do_symbols (VAR [OBARRAY [RESULTFORM]]) . BODY)
611 The VAR is bound to each of the symbols in OBARRAY (def. obarray) and
612 the BODY is repeatedly performed for each of those bindings. At the
613 end, RESULTFORM (def. nil) is evaluated and its value returned.
614 During this last evaluation, the VAR is still bound and its value is nil.
615 See also the function `mapatoms'."
616 ;; check sanity
627 ;; generate code
635 oblist)
638 resultform))))
642 "(do-all-symbols (VAR [RESULTFORM]) . BODY)
643 Is the same as (do-symbols (VAR obarray RESULTFORM) . BODY)."
645 'do-symbols
647 body))
648 \f
650 "(loop . BODY) repeats BODY indefinitely and does not return.
651 Normally BODY uses `throw' or `signal' to cause an exit.
652 The forms in BODY should be lists, as non-lists are reserved for new features."
653 ;; check that the body doesn't have atomic forms
656 ;; ok, it is a list, check for atomic components
661 body)
662 ;; build the infinite loop
665 ;;;; end of cl-iterations.el
666 \f
667 ;;;; LISTS
668 ;;;; This file provides some of the lists machinery of Common-Lisp
669 ;;;; in a way compatible with Emacs Lisp. Especially, see the the
670 ;;;; typical c[ad]*r functions.
671 ;;;;
672 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
673 ;;;; (quiroz@cs.rochester.edu)
689 "Generate code for (<accessor> FORM), where <accessor> is one of the named
690 list accessors: first, second, ..., tenth, rest."
713 ))))
715 ;;; Synonyms for list functions
717 "Synonym for `car'"
722 "Return the second element of the list LIST."
727 "Return the third element of the list LIST."
732 "Return the fourth element of the list LIST."
737 "Return the fifth element of the list LIST."
742 "Return the sixth element of the list LIST."
747 "Return the seventh element of the list LIST."
752 "Return the eighth element of the list LIST."
757 "Return the ninth element of the list LIST."
762 "Return the tenth element of the list LIST."
767 "Synonym for `cdr'"
770 \f
772 "t if X is nil, nil if X is a cons; error otherwise."
779 "Returns the last link in the list LIST."
787 "Returns the length of a non-circular list, or `nil' for a circular one."
803 \f
805 "Return a new list like LIST but sans the last N elements.
806 N defaults to 1. If the list doesn't have N elements, nil is returned."
811 "Return a new list containing the first arguments consed onto the last arg.
812 Thus, (list* 1 2 3 '(a b)) returns (1 2 3 a b)."
814 arg
819 front)))
822 "Return a list which contains ITEM but is otherwise like LIST.
823 If ITEM occurs in LIST, the value is LIST. Otherwise it is (cons ITEM LIST).
824 When comparing ITEM against elements, `eql' is used."
826 list
830 "Return a new list like LIST but sans SUBLIST.
831 SUBLIST must be one of the links in LIST; otherwise the value is LIST itself."
837 \f
838 ;;; The popular c[ad]*r functions and other list accessors.
840 ;;; To implement this efficiently, a new byte compile handler is used to
841 ;;; generate the minimal code, saving one function call.
844 "Generate code for a (c[ad]+r argument). This realizes the various
845 combinations of car and cdr whose names are supported in this implementation.
846 To use this functionality for a given function,just give its name a
847 'byte-compile property of 'byte-compile-ca*d*r"
854 ;; SEQ is a list of byte-car and byte-cdr in the correct order.
863 ;; the rest of this code doesn't change the stack depth!
869 "Return the car of the car of X."
874 "Return the car of the cdr of X."
879 "Return the cdr of the car of X."
884 "Return the cdr of the cdr of X."
889 "Return the car of the car of the car of X."
894 "Return the car of the car of the cdr of X."
899 "Return the car of the cdr of the car of X."
904 "Return the cdr of the car of the car of X."
909 "Return the car of the cdr of the cdr of X."
914 "Return the cdr of the car of the cdr of X."
919 "Return the cdr of the cdr of the car of X."
924 "Return the cdr of the cdr of the cdr of X."
929 "Return the car of the car of the car of the car of X."
934 "Return the car of the car of the car of the cdr of X."
939 "Return the car of the car of the cdr of the car of X."
944 "Return the car of the cdr of the car of the car of X."
949 "Return the cdr of the car of the car of the car of X."
954 "Return the car of the car of the cdr of the cdr of X."
959 "Return the car of the cdr of the car of the cdr of X."
964 "Return the cdr of the car of the car of the cdr of X."
969 "Return the car of the cdr of the cdr of the car of X."
974 "Return the cdr of the car of the cdr of the car of X."
979 "Return the cdr of the cdr of the car of the car of X."
984 "Return the car of the cdr of the cdr of the cdr of X."
989 "Return the cdr of the cdr of the car of the cdr of X."
994 "Return the cdr of the car of the cdr of the cdr of X."
999 "Return the cdr of the cdr of the cdr of the car of X."
1004 "Return the cdr of the cdr of the cdr of the cdr of X."
1007 \f
1008 ;;; some inverses of the accessors are needed for setf purposes
1011 "Set (nth N LIST) to NEWVAL. Returns NEWVAL."
1015 "(setnthcdr N LIST NEWVAL) => NEWVAL
1016 As a side effect, sets the Nth cdr of LIST to NEWVAL."
1022 newval)
1025 \f
1026 ;;; A-lists machinery
1029 "Return a new alist with KEY paired with ITEM; otherwise like ALIST.
1030 Does not copy ALIST."
1034 "Return a new alist with each elt of KEYS paired with an elt of DATA;
1035 optional 3rd arg ALIST is nconc'd at the end. KEYS and DATA must
1036 have the same length."
1048 \f
1049 ;;;; SEQUENCES
1050 ;;;; Emacs Lisp provides many of the 'sequences' functionality of
1051 ;;;; Common Lisp. This file provides a few things that were left out.
1052 ;;;;
1067 \f
1069 "Test PREDICATE on each element of SEQUENCE; is it ever non-nil?
1070 Extra args are additional sequences; PREDICATE gets one arg from each
1071 sequence and we advance down all the sequences together in lock-step.
1072 A sequence means either a list or a vector."
1088 "Test PREDICATE on each element of SEQUENCE; is it always non-nil?
1089 Extra args are additional sequences; PREDICATE gets one arg from each
1090 sequence and we advance down all the sequences together in lock-step.
1091 A sequence means either a list or a vector."
1105 \f
1107 "Test PREDICATE on each element of SEQUENCE; is it always nil?
1108 Extra args are additional sequences; PREDICATE gets one arg from each
1109 sequence and we advance down all the sequences together in lock-step.
1110 A sequence means either a list or a vector."
1126 "Test PREDICATE on each element of SEQUENCE; is it sometimes nil?
1127 Extra args are additional sequences; PREDICATE gets one arg from each
1128 sequence and we advance down all the sequences together in lock-step.
1129 A sequence means either a list or a vector."
1143 \f
1144 ;;; More sequence functions that don't need keyword arguments
1147 "(concatenate TYPE &rest SEQUENCES) => a sequence
1148 The sequence returned is of type TYPE (must be 'list, 'string, or 'vector) and
1149 contains the concatenation of the elements of all the arguments, in the order
1150 given."
1164 "(map TYPE FUNCTION &rest SEQUENCES) => a sequence
1165 The FUNCTION is called on each set of elements from the SEQUENCES \(stopping
1166 when the shortest sequence is terminated\) and the results are possibly
1167 returned in a sequence of type TYPE \(one of 'list, 'vector, 'string, or nil\)
1168 giving NIL for TYPE gets rid of the values."
1173 results)
1179 argslists))
1182 results)
1187 \f
1188 ;;; an inverse of elt is needed for setf purposes
1191 "In SEQUENCE, set the Nth element to NEWVAL. Returns NEWVAL.
1192 A sequence means either a list or a vector."
1196 ;; only two cases need be considered valid, as strings are arrays
1204 \f
1205 ;;; Testing with keyword arguments.
1206 ;;;
1207 ;;; Many of the sequence functions use keywords to denote some stylized
1208 ;;; form of selecting entries in a sequence. The involved arguments
1209 ;;; are collected with a &rest marker (as Emacs Lisp doesn't have a &key
1210 ;;; marker), then they are passed to build-klist, who
1211 ;;; constructs an association list. That association list is used to
1212 ;;; test for satisfaction and matching.
1214 ;;; DON'T USE MEMBER, NOR ANY FUNCTION THAT COULD TAKE KEYWORDS HERE!!!
1217 "Decode a keyword argument list ARGSLIST for keywords in ACCEPTABLE.
1218 ARGSLIST is a list, presumably the &rest argument of a call, whose
1219 even numbered elements must be keywords.
1220 ACCEPTABLE is a list of keywords, the only ones that are truly acceptable.
1221 The result is an alist containing the arguments named by the keywords
1222 in ACCEPTABLE, or an error is signalled, if something failed.
1223 If the third argument (an optional) is non-nil, other keys are acceptable."
1224 ;; check legality of the arguments, then destructure them
1240 keywords))
1244 nil
1246 keywords))
1256 ;; if THIS appears in auxlist, use its value
1262 "(extract-from-klist KLIST KEY [DEFAULT]) => value of KEY or DEFAULT
1263 Extract value associated with KEY in KLIST (return DEFAULT if nil)."
1268 "(keyword-argument-supplied-p KLIST KEY) => nil or something
1269 NIL if KEY (a keyword) does not appear in the KLIST."
1273 "(ADD-TO-KLIST KEY ITEM KLIST) => new KLIST
1274 Add association (KEY . ITEM) to KLIST."
1278 "(elt-satisfies-test-p ITEM ELT KLIST) => t or nil
1279 KLIST encodes a keyword-arguments test, as in CH. 14 of CLtL.
1280 True if the given ITEM and ELT satisfy the test."
1293 "(elt-satisfies-if-p ITEM KLIST) => t or nil
1294 True if an -if style function was called and ITEM satisfies the
1295 predicate under :predicate in KLIST."
1301 "(elt-satisfies-if-not-p ITEM KLIST) => t or nil
1302 KLIST encodes a keyword-arguments test, as in CH. 14 of CLtL.
1303 True if an -if-not style function was called and ITEM does not satisfy
1304 the predicate under :predicate in KLIST."
1310 "(elts-match-under-klist-p E1 E2 KLIST) => t or nil
1311 KLIST encodes a keyword-arguments test, as in CH. 14 of CLtL.
1312 True if elements E1 and E2 match under the tests encoded in KLIST."
1326 \f
1327 ;;; This macro simplifies using keyword args. It is less clumsy than using
1328 ;;; the primitives build-klist, etc... For instance, member could be written
1329 ;;; this way:
1331 ;;; (defun member (item list &rest kargs)
1332 ;;; (with-keyword-args kargs (test test-not (key 'identity))
1333 ;;; ...))
1335 ;;; Suggested by Robert Potter (potter@cs.rochester.edu, 15 Nov 1989)
1338 "(WITH-KEYWORD-ARGS KEYARGSLIST VARDEFS . BODY)
1339 KEYARGSLIST can be either a symbol or a list of one or two symbols.
1340 In the second case, the second symbol is either T or NIL, indicating whether
1341 keywords other than the mentioned ones are tolerable.
1343 VARDEFS is a list. Each entry is either a VAR (symbol) or matches
1344 \(VAR [DEFAULT [KEYWORD]]). Just giving VAR is the same as giving
1345 \(VAR nil :VAR).
1347 The BODY is executed in an environment where each VAR (a symbol) is bound to
1348 the value present in the KEYARGSLIST provided, or to the DEFAULT. The value
1349 is searched by using the keyword form of VAR (i.e., :VAR) or the optional
1350 keyword if provided.
1352 Notice that this macro doesn't distinguish between a default value given
1353 explicitly by the user and one provided by default. See also the more
1354 primitive functions build-klist, add-to-klist, extract-from-klist,
1355 keyword-argument-supplied-p, elt-satisfies-test-p, elt-satisfies-if-p,
1356 elt-satisfies-if-not-p, elts-match-under-klist-p. They provide more complete,
1357 if clumsier, control over this feature."
1362 "`%s' should be SYMBOL, (SYMBOL), or (SYMBOL t-OR-nil)"
1370 "first subform should be SYMBOL, (SYMBOL), or (SYMBOL t-OR-nil)"
1371 )))
1387 "`%s' must match (VAR [DEFAULT [KEYWORD]])"
1391 "bad variable `%s': must be non-null symbol"
1404 klistname
1405 k
1406 d))
1407 forms)))))
1408 vardefs)
1413 allow-other-keys)))
1415 body))))
1418 \f
1419 ;;; REDUCE
1420 ;;; It is here mostly as an example of how to use KLISTs.
1421 ;;;
1422 ;;; First of all, you need to declare the keywords (done elsewhere in this
1423 ;;; file):
1424 ;;; (defkeyword :from-end "syntax of sequence functions")
1425 ;;; (defkeyword :start "syntax of sequence functions")
1426 ;;; etc...
1427 ;;;
1428 ;;; Then, you capture all the possible keyword arguments with a &rest
1429 ;;; argument. You can pass that list downward again, of course, but
1430 ;;; internally you need to parse it into a KLIST (an alist, really). One uses
1431 ;;; (build-klist REST-ARGS ACCEPTABLE-KEYWORDS [ALLOW-OTHER]). You can then
1432 ;;; test for presence by using (keyword-argument-supplied-p KLIST KEY) and
1433 ;;; extract a value with (extract-from-klist KLIST KEY [DEFAULT]).
1436 "Apply FUNCTION (a function of two arguments) to succesive pairs of elements
1437 from SEQUENCE. Some keyword arguments are valid after FUNCTION and SEQUENCE:
1438 :from-end If non-nil, process the values backwards
1439 :initial-value If given, prefix it to the SEQUENCE. Suffix, if :from-end
1440 :start Restrict reduction to the subsequence from this index
1441 :end Restrict reduction to the subsequence BEFORE this index.
1442 If the sequence is empty and no :initial-value is given, the FUNCTION is
1443 called on zero (not two) arguments. Otherwise, if there is exactly one
1444 element in the combination of SEQUENCE and the initial value, that element is
1445 returned."
1458 sequence)))
1468 result))))
1471 "(cl$subseq-as-list SEQUENCE START END) => a list"
1474 result)
1480 list
1488 ;;;; end of cl-sequences.el
1489 \f
1490 ;;;; Some functions with keyword arguments
1491 ;;;;
1492 ;;;; Both list and sequence functions are considered here together. This
1493 ;;;; doesn't fit any more with the original split of functions in files.
1496 "Look for ITEM in LIST; return first tail of LIST the car of whose first
1497 cons cell tests the same as ITEM. Admits arguments :key, :test, and :test-not."
1504 ;; another workaround allegledly for speed
1512 ))
1518 ;; final hack: remove the indirection through the function names
1526 ;; ok, go for it
1541 result)))))
1542 \f
1543 ;;;; MULTIPLE VALUES
1544 ;;;; This package approximates the behavior of the multiple-values
1545 ;;;; forms of Common Lisp.
1546 ;;;;
1547 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
1548 ;;;; (quiroz@cs.rochester.edu)
1550 ;;; Lisp indentation information
1557 ;;; Global state of the package is kept here
1562 \f
1563 ;;; values is the standard multiple-value-return form. Must be the
1564 ;;; last thing evaluated inside a function. If the caller is not
1565 ;;; expecting multiple values, only the first one is passed. (values)
1566 ;;; is the same as no-values returned (unaware callers see nil). The
1567 ;;; alternative (values-list <list>) is just a convenient shorthand
1568 ;;; and complements multiple-value-list.
1571 "Produce multiple values (zero or more). Each arg is one value.
1572 See also `multiple-value-bind', which is one way to examine the
1573 multiple values produced by a form. If the containing form or caller
1574 does not check specially to see multiple values, it will see only
1575 the first value."
1581 "Produce multiple values (zero or mode). Each element of LIST is one value.
1582 This is equivalent to (apply 'values LIST)."
1589 \f
1590 ;;; Callers that want to see the multiple values use these macros.
1593 "Execute FORM and return a list of all the (multiple) values FORM produces.
1594 See `values' and `multiple-value-bind'."
1608 "Call FUNCTION on all the values produced by the remaining arguments.
1609 (multiple-value-call '+ (values 1 2) (values 3 4)) is 10."
1617 result
1622 "Bind VARS to the (multiple) values produced by FORM, then do BODY.
1623 VARS is a list of variables; each is bound to one of FORM's values.
1624 If FORM doesn't make enough values, the extra variables are bound to nil.
1625 (Ordinary forms produce only one value; to produce more, use `values'.)
1626 Extra values are ignored.
1627 BODY (zero or more forms) is executed with the variables bound,
1628 then the bindings are unwound."
1634 clauses)
1635 body)))
1636 \f
1638 "Set VARS to the (multiple) values produced by FORM.
1639 VARS is a list of variables; each is set to one of FORM's values.
1640 If FORM doesn't make enough values, the extra variables are set to nil.
1641 (Ordinary forms produce only one value; to produce more, use `values'.)
1642 Extra values are ignored."
1651 "Evaluate FORM, then BODY, then produce the same values FORM produced.
1652 Thus, (multiple-value-prog1 (values 1 2) (foobar)) produces values 1 and 2.
1653 This is like `prog1' except that `prog1' would produce only one value,
1654 which would be the first of FORM's values."
1660 ;;; utility functions
1661 ;;;
1662 ;;; mv-bind-clausify makes the pairs needed to have the variables in
1663 ;;; the variable list correspond with the values returned by the form.
1664 ;;; vals is a fresh symbol that intervenes in all the bindings.
1667 "MV-BIND-CLAUSIFY VARS VALS => Auxiliary list
1668 Forms a list of pairs `(,(nth i vars) (nth i vals)) for i from 0 to
1669 the length of VARS (a list of symbols). VALS is just a fresh symbol."
1680 ;;;; end of cl-multiple-values.el
1681 \f
1682 ;;;; ARITH
1683 ;;;; This file provides integer arithmetic extensions. Although
1684 ;;;; Emacs Lisp doesn't really support anything but integers, that
1685 ;;;; has still to be made to look more or less standard.
1686 ;;;;
1687 ;;;;
1688 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
1689 ;;;; (quiroz@cs.rochester.edu)
1693 "True if NUMBER is strictly greater than zero."
1697 "True if NUMBER is strictly less than zero."
1701 "True if INTEGER is not divisible by 2."
1705 "True if INTEGER is divisible by 2."
1709 "Return the absolute value of NUMBER."
1712 number))
1715 "Return -1, 0 or 1 according to the sign of NUMBER."
1722 \f
1724 "Return the greatest common divisor of all the arguments.
1725 The arguments must be integers. With no arguments, value is zero."
1736 ;; essentially the euclidean algorithm
1743 ;; intermediate results
1746 ;; final results
1756 "Return the least common multiple of all the arguments.
1757 The arguments must be integers and there must be at least one of them."
1761 prod ; intermediate product
1775 \f
1777 "Return the integer square root of NUMBER.
1778 NUMBER must not be negative. Result is largest integer less than or
1779 equal to the real square root of the argument."
1780 ;; The method used here is essentially the Newtonian iteration
1781 ;; x[n+1] <- (x[n] + Number/x[n]) / 2
1782 ;; suitably adapted to integer arithmetic.
1783 ;; Thanks to Philippe Schnoebelen <phs@lifia.imag.fr> for suggesting the
1784 ;; termination condition.
1787 number))
1796 approx))
1799 approx new)))))
1800 \f
1802 "Divide DIVIDEND by DIVISOR, rounding toward minus infinity.
1803 DIVISOR defaults to 1. The remainder is produced as a second value."
1823 "Divide DIVIDEND by DIVISOR, rounding toward plus infinity.
1824 DIVISOR defaults to 1. The remainder is produced as a second value."
1839 \f
1841 "Divide DIVIDEND by DIVISOR, rounding toward zero.
1842 DIVISOR defaults to 1. The remainder is produced as a second value."
1859 "Divide DIVIDEND by DIVISOR, rounding to nearest integer.
1860 DIVISOR defaults to 1. The remainder is produced as a second value."
1869 ;; adjust magnitudes first, and then signs
1875 ;; round to even is mandatory
1880 \f
1882 "Return remainder of X by Y (rounding quotient toward minus infinity).
1883 That is, the remainder goes with the quotient produced by `floor'."
1885 r))
1888 "Return remainder of X by Y (rounding quotient toward zero).
1889 That is, the remainder goes with the quotient produced by `truncate'."
1891 r))
1893 ;;; internal utilities
1894 ;;;
1895 ;;; safe-idiv performs an integer division with positive numbers only.
1896 ;;; It is known that some machines/compilers implement weird remainder
1897 ;;; computations when working with negatives, so the idea here is to
1898 ;;; make sure we know what is coming back to the caller in all cases.
1900 ;;; Signum computation fixed by mad@math.keio.JUNET (MAEDA Atusi)
1903 "SAFE-IDIV A B => Q R S
1904 Q=|A|/|B|, R is the rest, S is the sign of A/B."
1916 ;;;; end of cl-arith.el
1917 \f
1918 ;;;; SETF
1919 ;;;; This file provides the setf macro and friends. The purpose has
1920 ;;;; been modest, only the simplest defsetf forms are accepted.
1921 ;;;; Use it and enjoy.
1922 ;;;;
1923 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
1924 ;;;; (quiroz@cs.rochester.edu)
1928 "Property, its value is the function setf must invoke to update a
1929 generalized variable whose access form is a function call of the
1933 "Property of symbols that have a `defsetf' update function on them,
1935 \f
1937 "Generalized `setq' that can set things other than variable values.
1938 A use of `setf' looks like (setf {PLACE VALUE}...).
1939 The behavior of (setf PLACE VALUE) is to access the generalized variable
1940 at PLACE and store VALUE there. It returns VALUE. If there is more
1941 than one PLACE and VALUE, each PLACE is set from its VALUE before
1942 the next PLACE is evaluated."
1944 ;; check the number of subforms
1948 nil)
1950 ;; this is the recursive case
1960 result)))))
1962 ;; this is the base case (SETF PLACE VALUE)
1967 ;; dispatch on the type of the PLACE
1985 ;; this let gets new symbols to ensure adequate
1986 ;; order of evaluation of the subforms.
1988 bindings
1993 \f
1995 "Define how `setf' works on a certain kind of generalized variable.
1996 A use of `defsetf' looks like (defsetf ACCESSFN UPDATEFN [DOCSTRING]).
1997 ACCESSFN is a symbol. UPDATEFN is a function or macro which takes
1998 one more argument than ACCESSFN does. DEFSETF defines the translation
1999 of (SETF (ACCESFN . ARGS) NEWVAL) to be a form like (UPDATEFN ARGS... NEWVAL).
2000 The function UPDATEFN must return its last arg, after performing the
2001 updating called for."
2002 ;; reject ill-formed requests. too bad one can't test for functionp
2003 ;; or macrop.
2007 ;; update properties
2012 ;; any better thing to return?
2014 \f
2015 ;;; This section provides the "default" setfs for Common-Emacs-Lisp
2016 ;;; The user will not normally add anything to this, although
2017 ;;; defstruct will introduce new ones as a matter of fact.
2018 ;;;
2019 ;;; Apply is a special case. The Common Lisp
2020 ;;; standard makes the case of apply be useful when the user writes
2021 ;;; something like (apply #'name ...), Emacs Lisp doesn't have the #
2022 ;;; stuff, but it has (function ...). Notice that V18 includes a new
2023 ;;; apply: this file is compatible with V18 and pre-V18 Emacses.
2025 ;;; INCOMPATIBILITY: the SETF macro evaluates its arguments in the
2026 ;;; (correct) left to right sequence *before* checking for apply
2027 ;;; methods (which should really be an special case inside setf). Due
2028 ;;; to this, the lambda expression defsetf'd to apply will succeed in
2029 ;;; applying the right function even if the name was not quoted, but
2030 ;;; computed! That extension is not Common Lisp (nor is particularly
2031 ;;; useful, I think).
2035 ;; dissasemble the calling form
2036 ;; "(((quote fn) x1 x2 ... xn) val)" (function instead of quote, too)
2049 \f
2051 aset
2055 setnth
2059 setnthcdr
2063 setelt
2093 \f
2141 \f
2185 \f
2240 ;; how about defsetfing other Emacs forms?
2241 \f
2242 ;;; Modify macros
2243 ;;;
2244 ;;; It could be nice to implement define-modify-macro, but I don't
2245 ;;; think it really pays.
2248 "(incf REF [DELTA]) -> increment the g.v. REF by DELTA (default 1)"
2254 "(decf REF [DELTA]) -> decrement the g.v. REF by DELTA (default 1)"
2260 "(push ITEM REF) -> cons ITEM at the head of the g.v. REF (a list)"
2264 "(pushnew ITEM REF): adjoin ITEM at the head of the g.v. REF (a list)"
2268 "(pop REF) -> (prog1 (car REF) (setf REF (cdr REF)))"
2274 \f
2275 ;;; PSETF
2276 ;;;
2277 ;;; Psetf is the generalized variable equivalent of psetq. The right
2278 ;;; hand sides are evaluated and assigned (via setf) to the left hand
2279 ;;; sides. The evaluations are done in an environment where they
2280 ;;; appear to occur in parallel.
2283 "(psetf {var value }...) => nil
2284 Like setf, but all the values are computed before any assignment is made."
2288 length))
2290 '())
2303 setfs))))))
2304 setfs))))))
2305 \f
2306 ;;; SHIFTF and ROTATEF
2307 ;;;
2310 "(shiftf PLACE1 PLACE2... NEWVALUE)
2311 Set PLACE1 to PLACE2, PLACE2 to PLACE3...
2312 Each PLACE is set to the old value of the following PLACE,
2313 and the last PLACE is set to the value NEWVALUE.
2314 Returns the old value of PLACE1."
2319 ;; the places are accessed to fresh symbols
2330 "(rotatef PLACE...) sets each PLACE to the old value of the following PLACE.
2331 The last PLACE is set to the old value of the first PLACE.
2332 Thus, the values rotate through the PLACEs. Returns nil."
2334 nil
2339 'let bindings
2343 nil))))
2344 \f
2345 ;;;; STRUCTS
2346 ;;;; This file provides the structures mechanism. See the
2347 ;;;; documentation for Common-Lisp's defstruct. Mine doesn't
2348 ;;;; implement all the functionality of the standard, although some
2349 ;;;; more could be grafted if so desired. More details along with
2350 ;;;; the code.
2351 ;;;;
2352 ;;;;
2353 ;;;; Cesar Quiroz @ UofR DofCSc - Dec. 1986
2354 ;;;; (quiroz@cs.rochester.edu)
2376 \f
2378 "(defstruct NAME [DOC-STRING] . SLOTS) define NAME as structure type.
2379 NAME must be a symbol, the name of the new structure. It could also
2380 be a list (NAME . OPTIONS).
2382 Each option is either a symbol, or a list of a keyword symbol taken from the
2383 list \{:conc-name, :copier, :constructor, :predicate, :include,
2384 :print-function, :type, :initial-offset\}. The meanings of these are as in
2385 CLtL, except that no BOA-constructors are provided, and the options
2386 \{:print-fuction, :type, :initial-offset\} are ignored quietly. All these
2387 structs are named, in the sense that their names can be used for type
2388 discrimination.
2390 The DOC-STRING is established as the `structure-doc' property of NAME.
2392 The SLOTS are one or more of the following:
2393 SYMBOL -- meaning the SYMBOL is the name of a SLOT of NAME
2394 list of SYMBOL and VALUE -- meaning that VALUE is the initial value of
2395 the slot.
2396 `defstruct' defines functions `make-NAME', `NAME-p', `copy-NAME' for the
2397 structure, and functions with the same name as the slots to access
2398 them. `setf' of the accessors sets their values."
2402 ;; Names for the member functions come from the options. The
2403 ;; slots* stuff collects info about the slots declared explicitly.
2406 moreslotsn moreslots moreinits included)
2408 ;; The moreslots* stuff refers to slots gained as a consequence
2409 ;; of (:include clauses). -- Oct 89: Only one :include tolerated
2424 ;; compute properties of NAME
2429 docstring)
2431 slotsn)
2438 ;; If this definition :includes another defstruct,
2439 ;; modify both property lists.
2444 :structure-includes
2461 old
2462 :structure-included-in
2465 ;; careful with destructive
2466 ;;manipulation!
2468 'append
2470 'get
2471 old
2473 '())
2474 )))))
2477 :structure-includes
2478 '()))))
2479 ;; If this definition used to be :included in another, warn
2480 ;; that things make break. On the other hand, the redefinition
2481 ;; may be trivial, so don't call it an error.
2490 "`%s' redefined. Should redefine `%s'?"
2494 ;; Compute functions associated with NAME. This is not
2495 ;; handling BOA constructors yet, but here would be the place.
2511 'function
2521 'and
2523 typetag
2529 'memq
2530 typetag
2534 )))))
2535 ;; compute accessors for NAME's slots
2539 ;; generate returned value -- not defined by the standard
2546 ;; generate code
2549 accessors alterators returned))))))
2550 \f
2552 "(parse$defstruct$args ARGS) => NAME OPTIONS DOCSTRING SLOTSN SLOTS INITLIST
2553 NAME=symbol, OPTIONS=list of, DOCSTRING=string, SLOTSN=count of slots,
2554 SLOTS=list of their names, INITLIST=alist (keyword . initform)."
2556 options ;args=((symbol . options) ...)
2558 slotargs ;second or third cdr of args
2562 ;; extract name and options
2565 options '()))
2573 ;; is there a docstring?
2577 ;; now for the slots
2582 \f
2584 "(process$slots SLOTS) => SLOTSN SLOTSLIST INITLIST
2585 Converts a list of symbols or lists of symbol and form into the last 3
2586 values returned by PARSE$DEFSTRUCT$ARGS."
2588 slotslist ;(slot1 slot2 ...)
2601 ;; this silently ignores any slot options. bad...
2608 \f
2610 "(parse$defstruct$options name OPTIONS SLOTS) => many values
2611 A defstruct named NAME, with options list OPTIONS, has already slots SLOTS.
2612 Parse the OPTIONS and return the updated form of the struct's slots and other
2613 information. The values returned are:
2615 CONC-NAME is the string to use as prefix/suffix in the methods,
2616 CONST is the name of the official constructor,
2617 COPIER is the name of the structure copier,
2618 PRED is the name of the type predicate,
2619 MORESLOTSN is the number of slots added by :include,
2620 MORESLOTS is the list of slots added by :include,
2621 MOREINITS is the list of initialization forms added by :include,
2622 INCLUDED is nil, or the list of the symbol added by :include"
2624 ;; to build the return values
2632 ;; auxiliaries
2633 option-head ;When an option is not a plain
2634 option-second ; keyword, it must be a list of
2635 option-rest ; the form (head second . rest)
2636 these-slotsn ;When :include is found, the
2637 these-slots ; info about the included
2638 these-inits ; structure is added here.
2639 included ;NIL or (list INCLUDED)
2640 )
2641 ;; Values above are the defaults. Now we read the options themselves
2643 ;; 2 cases arise, as options must be a keyword or a list
2647 (:named
2657 (:conc-name
2661 option-second)
2667 (:copier
2672 option-second)
2676 \f
2682 option-second)
2686 (:predicate
2691 option-second)
2695 (:include
2731 ;; Return values found
2733 moreslotsn moreslots moreinits
2734 included)))
2735 \f
2737 "(simplify$inits SLOTS INITLIST) => new INITLIST
2738 Removes from INITLIST - an ALIST - any shadowed bindings."
2740 key ;from the slot
2741 )
2748 "(extract$indices INITLIST) => indices list
2749 Kludge. From a list of pairs (keyword . form) build a list of pairs
2750 of the form (keyword . position in list from 0). Useful to precompute
2751 some of the work of MAKE$STRUCTURE$INSTANCE."
2757 \f
2759 "(build$accessors$for NAME PREDICATE SLOTS SLOTSN) => FSETS DEFSETFS KWDS
2760 Generate the code for accesors and defsetfs of a structure called
2761 NAME, whose slots are SLOTS. Also, establishes the keywords for the
2762 slots names."
2782 "`%s' is not a struct %s"
2787 name))))))))
2788 accessors))
2798 "`%s' not a `%s'"
2803 name)))))))
2804 alterators))
2807 keywords))))
2808 \f
2810 "(make$structure$instance NAME ARGS) => new struct NAME
2811 A struct of type NAME is created, some slots might be initialized
2812 according to ARGS (the &rest argument of MAKE-name)."
2819 initalist ;pairlis'd on initforms
2820 initializers ;definitive initializers
2821 )
2822 ;; check sanity of the request
2830 ;; analyze the initializers provided by the call
2834 ;; check that all the arguments are introduced by keywords
2838 ;; check that all the keywords are known
2843 ;; update initforms
2853 result)))
2855 ;; compute definitive initializers
2864 ;; do real initialization
2868 ;;;; end of cl-structs.el
2869 \f
2870 ;;; For lisp-interaction mode, so that multiple values can be seen when passed
2871 ;;; back. Lies every now and then...
2885 "Evaluate sexp before point; print value\(s\) into current buffer.
2886 If the evaled form returns multiple values, they are shown one to a line.
2887 The variables -, +, ++, +++, *, **, ***, /, //, /// have their usual meaning.
2889 It clears the multiple-value passing mechanism, and does not pass back
2890 multiple values. Use this only if you are debugging cl.el and understand well
2891 how the multiple-value stuff works, because it can be fooled into believing
2892 that multiple values have been returned when they actually haven't, for
2893 instance
2894 \(identity \(values nil 1\)\)
2895 However, even when this fails, you can trust the first printed value to be
2896 \(one of\) the returned value\(s\)."
2898 ;; top level call, can reset mvalues
2912 ** *
2915 // /
2918 ++ +
2930 /)))
2933 \f
2934 ;;;; More LISTS functions
2935 ;;;;
2937 ;;; Some mapping functions on lists, commonly useful.
2938 ;;; They take no extra sequences, to go along with Emacs Lisp's MAPCAR.
2941 "(MAPC FUNCTION LIST) => LIST
2942 Apply FUNCTION to each element of LIST, return LIST.
2943 Like mapcar, but called only for effect."
2948 list)
2951 "(MAPLIST FUNCTION LIST) => list'ed results of FUNCTION on cdrs of LIST
2952 Apply FUNCTION to successive sublists of LIST, return the list of the results"
2954 results '())
2961 "(MAPL FUNCTION LIST) => LIST
2962 Apply FUNCTION to successive cdrs of LIST, return LIST.
2963 Like maplist, but called only for effect."
2968 list))
2971 "(MAPCAN FUNCTION LIST) => nconc'd results of FUNCTION on LIST
2972 Apply FUNCTION to each element of LIST, nconc the results.
2973 Beware: nconc destroys its first argument! See copy-list."
2982 "(MAPCON FUNCTION LIST) => nconc'd results of FUNCTION on cdrs of LIST
2983 Apply FUNCTION to successive sublists of LIST, nconc the results.
2984 Beware: nconc destroys its first argument! See copy-list."
2992 ;;; Copiers
2995 "Build a copy of LIST"
2999 "Build a copy of the tree of conses TREE
3000 The argument is a tree of conses, it is recursively copied down to
3001 non conses. Circularity and sharing of substructure are not
3002 necessarily preserved."
3006 tree))
3008 ;;; reversals, and destructive manipulations of a list's spine
3011 "does what (append (reverse X) Y) would, only faster"
3013 y
3017 "does (nconc (nreverse X) Y) would, only faster
3018 Destructive on X, be careful."
3020 y
3021 ;; reuse the first cons of x, making it point to y
3025 "Side-effected LIST truncated N+1 conses from the end.
3026 This is the destructive version of BUTLAST. Returns () and does not
3027 modify the LIST argument if the length of the list is not at least N."
3031 list)
3033 '())
3036 list))))
3037 \f
3038 ;;; Substitutions
3041 "NEW replaces OLD in a copy of TREE
3042 Uses eql for the test."
3046 "NEW replaces any subtree or leaf that fails TEST in a copy of TREE"
3047 ;; (subst-if new (function (lambda (x) (not (funcall test x)))) tree)
3049 new)
3051 tree)
3055 ;; If nothing changed, return originals. Else use the new
3056 ;; components to assemble a new tree.
3059 tree
3063 "NEW replaces any subtree or leaf that satisfies TEST in a copy of TREE"
3065 new)
3067 tree)
3071 ;; If nothing changed, return originals. Else use the new
3072 ;; components to assemble a new tree.
3075 tree
3079 "Use association list ALIST to modify a copy of TREE
3080 If a subtree or leaf of TREE is a key in ALIST, it is replaced by the
3081 associated value. Not exactly Common Lisp, but close in spirit and
3082 compatible with the native Emacs Lisp ASSOC, which uses EQUAL."
3087 tree)
3093 tree
3097 "PREDICATE is applied to the members of LIST. As soon as one of them
3098 returns true, that tail of the list if returned. Else NIL."
3104 nil))
3107 "PREDICATE is applied to the members of LIST. As soon as one of them
3108 returns false, that tail of the list if returned. Else NIL."
3114 nil))
3117 "(tailp SUBLIST LIST) => True if SUBLIST is a sublist of LIST."
3123 nil))
3124 \f
3125 ;;; Suggestion of phr%widow.Berkeley.EDU@lilac.berkeley.edu
3128 "Ignore a Common-Lisp declaration."
3132 "Ignore a Common-Lisp proclamation."
3136 "(the TYPE FORM) macroexpands to FORM
3137 No checking is even attempted. This is just for compatibility with
3138 Common-Lisp codes."
3139 form)
3143 ;;; cl.el ends here