;;; not really an old-fashioned function, but what the calling
;;; convention should've been: like NTH, but with the same argument
-;;; order as in all the other dereferencing functions, with the
-;;; collection first and the index second
+;;; order as in all the other indexed dereferencing functions, with
+;;; the collection first and the index second
(declaim (inline nth-but-with-sane-arg-order))
(declaim (ftype (function (list index) t) nth-but-with-sane-arg-order))
(defun nth-but-with-sane-arg-order (list index)
\f
;;;; miscellaneous iteration extensions
-;;; "the ultimate iteration macro"
+;;; like Scheme's named LET
;;;
-;;; note for Schemers: This seems to be identical to Scheme's "named LET".
+;;; (CMU CL called this ITERATE, and commented it as "the ultimate
+;;; iteration macro...". I (WHN) found the old name insufficiently
+;;; specific to remind me what the macro means, so I renamed it.)
(defmacro named-let (name binds &body body)
- #!+sb-doc
(dolist (x binds)
(unless (proper-list-of-length-p x 2)
(error "malformed NAMED-LET variable spec: ~S" x)))
(def-constantly-fun constantly-nil nil)
(def-constantly-fun constantly-0 0))
-;;; If X is an atom, see whether it is present in *FEATURES*. Also
+;;; If X is a symbol, see whether it is present in *FEATURES*. Also
;;; handle arbitrary combinations of atoms using NOT, AND, OR.
(defun featurep (x)
- (if (consp x)
- (case (car x)
- ((:not not)
- (if (cddr x)
- (error "too many subexpressions in feature expression: ~S" x)
- (not (featurep (cadr x)))))
- ((:and and) (every #'featurep (cdr x)))
- ((:or or) (some #'featurep (cdr x)))
- (t
- (error "unknown operator in feature expression: ~S." x)))
- (not (null (memq x *features*)))))
-
-;;; Given a list of keyword substitutions `(,OLD ,NEW), and a
-;;; &KEY-argument-list-style list of alternating keywords and
-;;; arbitrary values, return a new &KEY-argument-list-style list with
-;;; all substitutions applied to it.
-;;;
-;;; Note: If efficiency mattered, we could do less consing. (But if
-;;; efficiency mattered, why would we be using &KEY arguments at
-;;; all, much less renaming &KEY arguments?)
-;;;
-;;; KLUDGE: It would probably be good to get rid of this. -- WHN 19991201
-(defun rename-key-args (rename-list key-args)
- (declare (type list rename-list key-args))
- ;; Walk through RENAME-LIST modifying RESULT as per each element in
- ;; RENAME-LIST.
- (do ((result (copy-list key-args))) ; may be modified below
- ((null rename-list) result)
- (destructuring-bind (old new) (pop rename-list)
- ;; ANSI says &KEY arg names aren't necessarily KEYWORDs.
- (declare (type symbol old new))
- ;; Walk through RESULT renaming any OLD key argument to NEW.
- (do ((in-result result (cddr in-result)))
- ((null in-result))
- (declare (type list in-result))
- (when (eq (car in-result) old)
- (setf (car in-result) new))))))
-
-;;; ANSI Common Lisp's READ-SEQUENCE function, unlike most of the
-;;; other ANSI input functions, is defined to communicate end of file
-;;; status with its return value, not by signalling. That is not the
-;;; behavior that we usually want. This function is a wrapper which
-;;; restores the behavior that we usually want, causing READ-SEQUENCE
-;;; to communicate end-of-file status by signalling.
-(defun read-sequence-or-die (sequence stream &key start end)
- ;; implementation using READ-SEQUENCE
- #-no-ansi-read-sequence
- (let ((read-end (read-sequence sequence
- stream
- :start start
- :end end)))
- (unless (= read-end end)
- (error 'end-of-file :stream stream))
- (values))
- ;; workaround for broken READ-SEQUENCE
- #+no-ansi-read-sequence
- (progn
- (aver (<= start end))
- (let ((etype (stream-element-type stream)))
- (cond ((equal etype '(unsigned-byte 8))
- (do ((i start (1+ i)))
- ((>= i end)
- (values))
- (setf (aref sequence i)
- (read-byte stream))))
- (t (error "unsupported element type ~S" etype))))))
+ (etypecase x
+ (cons
+ (case (car x)
+ ((:not not)
+ (cond
+ ((cddr x)
+ (error "too many subexpressions in feature expression: ~S" x))
+ ((null (cdr x))
+ (error "too few subexpressions in feature expression: ~S" x))
+ (t (not (featurep (cadr x))))))
+ ((:and and) (every #'featurep (cdr x)))
+ ((:or or) (some #'featurep (cdr x)))
+ (t
+ (error "unknown operator in feature expression: ~S." x))))
+ (symbol (not (null (memq x *features*))))))
\f
;;;; utilities for two-VALUES predicates
;;; to force DX allocation in their bodies, which would be bad eg.
;;; in safe code.
(defmacro dx-flet (functions &body forms)
- `(flet ,functions
- (declare (optimize sb!c::stack-allocate-dynamic-extent))
- (flet ,(mapcar
- (lambda (f)
- (let ((args (cadr f))
- (name (car f)))
- (when (intersection args lambda-list-keywords)
- ;; No fundamental reason not to support them, but we
- ;; don't currently need them here.
- (error "Non-required arguments not implemented for DX-FLET."))
- `(,name ,args
- (,name ,@args))))
- functions)
- (declare (dynamic-extent ,@(mapcar (lambda (f)
- `(function ,(car f)))
- functions)))
+ (let ((names (mapcar #'car functions)))
+ `(flet ,functions
+ #-sb-xc-host
+ (declare (optimize sb!c::stack-allocate-dynamic-extent))
+ (flet ,(mapcar
+ (lambda (f)
+ (let ((args (cadr f))
+ (name (car f)))
+ (when (intersection args lambda-list-keywords)
+ ;; No fundamental reason not to support them, but we
+ ;; don't currently need them here.
+ (error "Non-required arguments not implemented for DX-FLET."))
+ `(,name ,args
+ (,name ,@args))))
+ functions)
+ (declare (dynamic-extent ,@(mapcar (lambda (x) `(function ,x)) names)))
+ ,@forms))))
+
+;;; Another similar one -- but actually touches the policy of the body,
+;;; so take care with this one...
+(defmacro dx-let (bindings &body forms)
+ `(locally
+ #-sb-xc-host
+ (declare (optimize sb!c::stack-allocate-dynamic-extent))
+ (let ,bindings
+ (declare (dynamic-extent ,@(mapcar (lambda (bind)
+ (if (consp bind)
+ (car bind)
+ bind))
+ bindings)))
,@forms)))
+
projects / sbcl.git / blobdiff