GopherProxy

	tlists.lisp - clic - Clic is an command line interactive client for gopher writ…
	git clone git://bitreich.org/clic/ git://hg6vgqziawt5s4dj.onion/clic/
	Log
	Files
	Refs
	Tags
	LICENSE
	---
	tlists.lisp (14051B)
	---
	1 (in-package :alexandria)
	2
	3 (declaim (inline safe-endp))
	4 (defun safe-endp (x)
	5 (declare (optimize safety))
	6 (endp x))
	7
	8 (defun alist-plist (alist)
	9 "Returns a property list containing the same keys and values as the
	10 association list ALIST in the same order."
	11 (let (plist)
	12 (dolist (pair alist)
	13 (push (car pair) plist)
	14 (push (cdr pair) plist))
	15 (nreverse plist)))
	16
	17 (defun plist-alist (plist)
	18 "Returns an association list containing the same keys and values as the
	19 property list PLIST in the same order."
	20 (let (alist)
	21 (do ((tail plist (cddr tail)))
	22 ((safe-endp tail) (nreverse alist))
	23 (push (cons (car tail) (cadr tail)) alist))))
	24
	25 (declaim (inline racons))
	26 (defun racons (key value ralist)
	27 (acons value key ralist))
	28
	29 (macrolet
	30 ((define-alist-get (name get-entry get-value-from-entry add doc)
	31 `(progn
	32 (declaim (inline ,name))
	33 (defun ,name (alist key &key (test 'eql))
	34 ,doc
	35 (let ((entry (,get-entry key alist :test test)))
	36 (values (,get-value-from-entry entry) entry)))
	37 (define-setf-expander ,name (place key &key (test ''eql)
	38 &environment env)
	39 (multiple-value-bind
	40 (temporary-variables initforms newvals setter getter)
	41 (get-setf-expansion place env)
	42 (when (cdr newvals)
	43 (error "~A cannot store multiple values in one place" ',…
	44 (with-unique-names (new-value key-val test-val alist entry)
	45 (values
	46 (append temporary-variables
	47 (list alist
	48 key-val
	49 test-val
	50 entry))
	51 (append initforms
	52 (list getter
	53 key
	54 test
	55 `(,',get-entry ,key-val ,alist :test ,tes…
	56 `(,new-value)
	57 `(cond
	58 (,entry
	59 (setf (,',get-value-from-entry ,entry) ,new-value))
	60 (t
	61 (let ,newvals
	62 (setf ,(first newvals) (,',add ,key ,new-value ,a…
	63 ,setter
	64 ,new-value)))
	65 `(,',get-value-from-entry ,entry))))))))
	66 (define-alist-get assoc-value assoc cdr acons
	67 "ASSOC-VALUE is an alist accessor very much like ASSOC, but it can
	68 be used with SETF.")
	69 (define-alist-get rassoc-value rassoc car racons
	70 "RASSOC-VALUE is an alist accessor very much like RASSOC, but it can
	71 be used with SETF."))
	72
	73 (defun malformed-plist (plist)
	74 (error "Malformed plist: ~S" plist))
	75
	76 (defmacro doplist ((key val plist &optional values) &body body)
	77 "Iterates over elements of PLIST. BODY can be preceded by
	78 declarations, and is like a TAGBODY. RETURN may be used to terminate
	79 the iteration early. If RETURN is not used, returns VALUES."
	80 (multiple-value-bind (forms declarations) (parse-body body)
	81 (with-gensyms (tail loop results)
	82 `(block nil
	83 (flet ((,results ()
	84 (let (,key ,val)
	85 (declare (ignorable ,key ,val))
	86 (return ,values))))
	87 (let* ((,tail ,plist)
	88 (,key (if ,tail
	89 (pop ,tail)
	90 (,results)))
	91 (,val (if ,tail
	92 (pop ,tail)
	93 (malformed-plist ',plist))))
	94 (declare (ignorable ,key ,val))
	95 ,@declarations
	96 (tagbody
	97 ,loop
	98 ,@forms
	99 (setf ,key (if ,tail
	100 (pop ,tail)
	101 (,results))
	102 ,val (if ,tail
	103 (pop ,tail)
	104 (malformed-plist ',plist)))
	105 (go ,loop))))))))
	106
	107 (define-modify-macro appendf (&rest lists) append
	108 "Modify-macro for APPEND. Appends LISTS to the place designated by the…
	109 argument.")
	110
	111 (define-modify-macro nconcf (&rest lists) nconc
	112 "Modify-macro for NCONC. Concatenates LISTS to place designated by the…
	113 argument.")
	114
	115 (define-modify-macro unionf (list &rest args) union
	116 "Modify-macro for UNION. Saves the union of LIST and the contents of t…
	117 place designated by the first argument to the designated place.")
	118
	119 (define-modify-macro nunionf (list &rest args) nunion
	120 "Modify-macro for NUNION. Saves the union of LIST and the contents of …
	121 place designated by the first argument to the designated place. May modi…
	122 either argument.")
	123
	124 (define-modify-macro reversef () reverse
	125 "Modify-macro for REVERSE. Copies and reverses the list stored in the …
	126 place and saves back the result into the place.")
	127
	128 (define-modify-macro nreversef () nreverse
	129 "Modify-macro for NREVERSE. Reverses the list stored in the given plac…
	130 destructively modifying it and saves back the result into the place.")
	131
	132 (defun circular-list (&rest elements)
	133 "Creates a circular list of ELEMENTS."
	134 (let ((cycle (copy-list elements)))
	135 (nconc cycle cycle)))
	136
	137 (defun circular-list-p (object)
	138 "Returns true if OBJECT is a circular list, NIL otherwise."
	139 (and (listp object)
	140 (do ((fast object (cddr fast))
	141 (slow (cons (car object) (cdr object)) (cdr slow)))
	142 (nil)
	143 (unless (and (consp fast) (listp (cdr fast)))
	144 (return nil))
	145 (when (eq fast slow)
	146 (return t)))))
	147
	148 (defun circular-tree-p (object)
	149 "Returns true if OBJECT is a circular tree, NIL otherwise."
	150 (labels ((circularp (object seen)
	151 (and (consp object)
	152 (do ((fast (cons (car object) (cdr object)) (cddr fast…
	153 (slow object (cdr slow)))
	154 (nil)
	155 (when (or (eq fast slow) (member slow seen))
	156 (return-from circular-tree-p t))
	157 (when (or (not (consp fast)) (not (consp (cdr slow))…
	158 (return
	159 (do ((tail object (cdr tail)))
	160 ((not (consp tail))
	161 nil)
	162 (let ((elt (car tail)))
	163 (circularp elt (cons object seen))))))))))
	164 (circularp object nil)))
	165
	166 (defun proper-list-p (object)
	167 "Returns true if OBJECT is a proper list."
	168 (cond ((not object)
	169 t)
	170 ((consp object)
	171 (do ((fast object (cddr fast))
	172 (slow (cons (car object) (cdr object)) (cdr slow)))
	173 (nil)
	174 (unless (and (listp fast) (consp (cdr fast)))
	175 (return (and (listp fast) (not (cdr fast)))))
	176 (when (eq fast slow)
	177 (return nil))))
	178 (t
	179 nil)))
	180
	181 (deftype proper-list ()
	182 "Type designator for proper lists. Implemented as a SATISFIES type, he…
	183 not recommended for performance intensive use. Main usefullness as a type
	184 designator of the expected type in a TYPE-ERROR."
	185 `(and list (satisfies proper-list-p)))
	186
	187 (defun circular-list-error (list)
	188 (error 'type-error
	189 :datum list
	190 :expected-type '(and list (not circular-list))))
	191
	192 (macrolet ((def (name lambda-list doc step declare ret1 ret2)
	193 (assert (member 'list lambda-list))
	194 `(defun ,name ,lambda-list
	195 ,doc
	196 (do ((last list fast)
	197 (fast list (cddr fast))
	198 (slow (cons (car list) (cdr list)) (cdr slow))
	199 ,@(when step (list step)))
	200 (nil)
	201 (declare (dynamic-extent slow) ,@(when declare (list d…
	202 (ignorable last))
	203 (when (safe-endp fast)
	204 (return ,ret1))
	205 (when (safe-endp (cdr fast))
	206 (return ,ret2))
	207 (when (eq fast slow)
	208 (circular-list-error list))))))
	209 (def proper-list-length (list)
	210 "Returns length of LIST, signalling an error if it is not a proper l…
	211 (n 1 (+ n 2))
	212 ;; KLUDGE: Most implementations don't actually support lists with bi…
	213 ;; elements -- and this is WAY faster on most implementations then d…
	214 ;; N to be an UNSIGNED-BYTE.
	215 (fixnum n)
	216 (1- n)
	217 n)
	218
	219 (def lastcar (list)
	220 "Returns the last element of LIST. Signals a type-error if LIST is…
	221 proper list."
	222 nil
	223 nil
	224 (cadr last)
	225 (car fast))
	226
	227 (def (setf lastcar) (object list)
	228 "Sets the last element of LIST. Signals a type-error if LIST is no…
	229 list."
	230 nil
	231 nil
	232 (setf (cadr last) object)
	233 (setf (car fast) object)))
	234
	235 (defun make-circular-list (length &key initial-element)
	236 "Creates a circular list of LENGTH with the given INITIAL-ELEMENT."
	237 (let ((cycle (make-list length :initial-element initial-element)))
	238 (nconc cycle cycle)))
	239
	240 (deftype circular-list ()
	241 "Type designator for circular lists. Implemented as a SATISFIES type, …
	242 recommended for performance intensive use. Main usefullness as the
	243 expected-type designator of a TYPE-ERROR."
	244 `(satisfies circular-list-p))
	245
	246 (defun ensure-car (thing)
	247 "If THING is a CONS, its CAR is returned. Otherwise THING is returned."
	248 (if (consp thing)
	249 (car thing)
	250 thing))
	251
	252 (defun ensure-cons (cons)
	253 "If CONS is a cons, it is returned. Otherwise returns a fresh cons wit…
	254 in the car, and NIL in the cdr."
	255 (if (consp cons)
	256 cons
	257 (cons cons nil)))
	258
	259 (defun ensure-list (list)
	260 "If LIST is a list, it is returned. Otherwise returns the list designa…
	261 (if (listp list)
	262 list
	263 (list list)))
	264
	265 (defun remove-from-plist (plist &rest keys)
	266 "Returns a propery-list with same keys and values as PLIST, except tha…
	267 in the list designated by KEYS and values corresponding to them are remo…
	268 The returned property-list may share structure with the PLIST, but PLIST…
	269 not destructively modified. Keys are compared using EQ."
	270 (declare (optimize (speed 3)))
	271 ;; FIXME: possible optimization: (remove-from-plist '(:x 0 :a 1 :b 2) …
	272 ;; could return the tail without consing up a new list.
	273 (loop for (key . rest) on plist by #'cddr
	274 do (assert rest () "Expected a proper plist, got ~S" plist)
	275 unless (member key keys :test #'eq)
	276 collect key and collect (first rest)))
	277
	278 (defun delete-from-plist (plist &rest keys)
	279 "Just like REMOVE-FROM-PLIST, but this version may destructively modif…
	280 provided PLIST."
	281 (declare (optimize speed))
	282 (loop with head = plist
	283 with tail = nil ; a nil tail means an empty result so far
	284 for (key . rest) on plist by #'cddr
	285 do (assert rest () "Expected a proper plist, got ~S" plist)
	286 (if (member key keys :test #'eq)
	287 ;; skip over this pair
	288 (let ((next (cdr rest)))
	289 (if tail
	290 (setf (cdr tail) next)
	291 (setf head next)))
	292 ;; keep this pair
	293 (setf tail rest))
	294 finally (return head)))
	295
	296 (define-modify-macro remove-from-plistf (&rest keys) remove-from-plist
	297 "Modify macro for REMOVE-FROM-PLIST.")
	298 (define-modify-macro delete-from-plistf (&rest keys) delete-from-plist
	299 "Modify macro for DELETE-FROM-PLIST.")
	300
	301 (declaim (inline sans))
	302 (defun sans (plist &rest keys)
	303 "Alias of REMOVE-FROM-PLIST for backward compatibility."
	304 (apply #'remove-from-plist plist keys))
	305
	306 (defun mappend (function &rest lists)
	307 "Applies FUNCTION to respective element(s) of each LIST, appending all…
	308 all the result list to a single list. FUNCTION must return a list."
	309 (loop for results in (apply #'mapcar function lists)
	310 append results))
	311
	312 (defun setp (object &key (test #'eql) (key #'identity))
	313 "Returns true if OBJECT is a list that denotes a set, NIL otherwise. A…
	314 denotes a set if each element of the list is unique under KEY and TEST."
	315 (and (listp object)
	316 (let (seen)
	317 (dolist (elt object t)
	318 (let ((key (funcall key elt)))
	319 (if (member key seen :test test)
	320 (return nil)
	321 (push key seen)))))))
	322
	323 (defun set-equal (list1 list2 &key (test #'eql) (key nil keyp))
	324 "Returns true if every element of LIST1 matches some element of LIST2 …
	325 every element of LIST2 matches some element of LIST1. Otherwise returns …
	326 (let ((keylist1 (if keyp (mapcar key list1) list1))
	327 (keylist2 (if keyp (mapcar key list2) list2)))
	328 (and (dolist (elt keylist1 t)
	329 (or (member elt keylist2 :test test)
	330 (return nil)))
	331 (dolist (elt keylist2 t)
	332 (or (member elt keylist1 :test test)
	333 (return nil))))))
	334
	335 (defun map-product (function list &rest more-lists)
	336 "Returns a list containing the results of calling FUNCTION with one ar…
	337 from LIST, and one from each of MORE-LISTS for each combination of argum…
	338 In other words, returns the product of LIST and MORE-LISTS using FUNCTIO…
	339
	340 Example:
	341
	342 (map-product 'list '(1 2) '(3 4) '(5 6))
	343 => ((1 3 5) (1 3 6) (1 4 5) (1 4 6)
	344 (2 3 5) (2 3 6) (2 4 5) (2 4 6))
	345 "
	346 (labels ((%map-product (f lists)
	347 (let ((more (cdr lists))
	348 (one (car lists)))
	349 (if (not more)
	350 (mapcar f one)
	351 (mappend (lambda (x)
	352 (%map-product (curry f x) more))
	353 one)))))
	354 (%map-product (ensure-function function) (cons list more-lists))))
	355
	356 (defun flatten (tree)
	357 "Traverses the tree in order, collecting non-null leaves into a list."
	358 (let (list)
	359 (labels ((traverse (subtree)
	360 (when subtree
	361 (if (consp subtree)
	362 (progn
	363 (traverse (car subtree))
	364 (traverse (cdr subtree)))
	365 (push subtree list)))))
	366 (traverse tree))
	367 (nreverse list)))