;;;; provided with absolutely no warranty. See the COPYING and CREDITS
;;;; files for more information.
-(in-package "SB!INT")
+(in-package "SB!IMPL")
\f
;;;; target constants which need to appear as early as possible
;;; and there's also the noted-below problem that the C-level code
;;; contains implicit assumptions about this marker.
;;;
-;;; KLUDGE: Note that as of version 0.6.6 there's a dependence in the
+;;; KLUDGE: Note that as of version 0.pre7 there's a dependence in the
;;; gencgc.c code on this value being a symbol. (This is only one of
-;;; many nasty dependencies between that code and this, alas.)
-;;; -- WHN 2001-02-28
-;;;
-;;; FIXME: We end up doing two DEFCONSTANT forms because (1) LispWorks
-;;; needs EVAL-WHEN wrapped around DEFCONSTANT, and (2) SBCL's
-;;; DEFCONSTANT expansion doesn't seem to behave properly inside
-;;; EVAL-WHEN, so that without this, the +EMPTY-HT-SLOT+ references in
-;;; e.g. DOHASH macroexpansions don't end up being replaced by
-;;; constant values, so that the system dies at cold init because
-;;; '+EMPTY-HT-SLOT+ isn't bound yet. It's hard to fix this properly
-;;; until SBCL's EVAL-WHEN is fixed, which is waiting for the IR1
-;;; interpreter to go away, which is waiting for sbcl-0.7.x..
+;;; several nasty dependencies between that code and this, alas.)
+;;; -- WHN 2001-08-17
(eval-when (:compile-toplevel :load-toplevel :execute)
- (defconstant +empty-ht-slot+ '%empty-ht-slot%))
-(defconstant +empty-ht-slot+ '#.+empty-ht-slot+) ; egads.. See FIXME above.
+ (def!constant +empty-ht-slot+ '%empty-ht-slot%))
+;;; We shouldn't need this mess now that EVAL-WHEN works.
+
;;; KLUDGE: Using a private symbol still leaves us vulnerable to users
;;; getting nonconforming behavior by messing around with
;;; DO-ALL-SYMBOLS. That seems like a fairly obscure problem, so for
\f
;;;; DO-related stuff which needs to be visible on the cross-compilation host
-(eval-when (:compile-toplevel :load-toplevel :execute)
- (defun do-do-body (varlist endlist decls-and-code bind step name block)
+(eval-when (#-sb-xc :compile-toplevel :load-toplevel :execute)
+ (defun frob-do-body (varlist endlist decls-and-code bind step name block)
(let* ((r-inits nil) ; accumulator for reversed list
(r-steps nil) ; accumulator for reversed list
(label-1 (gensym))
;;; EXIT-FORMS are evaluated as a PROGN, with the result being the
;;; value of the DO.
(defmacro do-anonymous (varlist endlist &rest body)
- (do-do-body varlist endlist body 'let 'psetq 'do-anonymous (gensym)))
+ (frob-do-body varlist endlist body 'let 'psetq 'do-anonymous (gensym)))
+\f
+;;;; GENSYM tricks
+
+;;; Automate an idiom often found in macros:
+;;; (LET ((FOO (GENSYM "FOO"))
+;;; (MAX-INDEX (GENSYM "MAX-INDEX-")))
+;;; ...)
+;;;
+;;; "Good notation eliminates thought." -- Eric Siggia
+;;;
+;;; Incidentally, this is essentially the same operator which
+;;; _On Lisp_ calls WITH-GENSYMS.
+(defmacro with-unique-names (symbols &body body)
+ `(let ,(mapcar (lambda (symbol)
+ (let* ((symbol-name (symbol-name symbol))
+ (stem (if (every #'alpha-char-p symbol-name)
+ symbol-name
+ (concatenate 'string symbol-name "-"))))
+ `(,symbol (gensym ,stem))))
+ symbols)
+ ,@body))
+
+;;; Return a list of N gensyms. (This is a common suboperation in
+;;; macros and other code-manipulating code.)
+(declaim (ftype (function (index) list) make-gensym-list))
+(defun make-gensym-list (n)
+ (loop repeat n collect (gensym)))
\f
;;;; miscellany
+;;; Lots of code wants to get to the KEYWORD package or the
+;;; COMMON-LISP package without a lot of fuss, so we cache them in
+;;; variables. TO DO: How much does this actually buy us? It sounds
+;;; sensible, but I don't know for sure that it saves space or time..
+;;; -- WHN 19990521
+;;;
+;;; (The initialization forms here only matter on the cross-compilation
+;;; host; In the target SBCL, these variables are set in cold init.)
+(declaim (type package *cl-package* *keyword-package*))
+(defvar *cl-package* (find-package "COMMON-LISP"))
+(defvar *keyword-package* (find-package "KEYWORD"))
+
;;; Concatenate together the names of some strings and symbols,
;;; producing a symbol in the current package.
-(eval-when (:compile-toplevel :load-toplevel :execute)
+(eval-when (#-sb-xc :compile-toplevel :load-toplevel :execute)
(defun symbolicate (&rest things)
- (values (intern (apply #'concatenate
- 'string
- (mapcar #'string things))))))
+ (let ((name (case (length things)
+ ;; why isn't this just the value in the T branch?
+ ;; Well, this is called early in cold-init, before
+ ;; the type system is set up; however, now that we
+ ;; check for bad lengths, the type system is needed
+ ;; for calls to CONCATENATE. So we need to make sure
+ ;; that the calls are transformed away:
+ (1 (concatenate 'string
+ (the simple-base-string (string (car things)))))
+ (2 (concatenate 'string
+ (the simple-base-string (string (car things)))
+ (the simple-base-string (string (cadr things)))))
+ (3 (concatenate 'string
+ (the simple-base-string (string (car things)))
+ (the simple-base-string (string (cadr things)))
+ (the simple-base-string (string (caddr things)))))
+ (t (apply #'concatenate 'string (mapcar #'string things))))))
+ (values (intern name)))))
;;; like SYMBOLICATE, but producing keywords
(defun keywordicate (&rest things)
(if (consp id)
(values (car id) (cdr id))
(values id nil))
- (push `(defconstant ,(symbolicate prefix root suffix)
+ (push `(def!constant ,(symbolicate prefix root suffix)
,(+ start (* step index))
,@docs)
results)))
;;; structure for each object file which contains code referring to
;;; the value, plus perhaps one more copy bound to the SYMBOL-VALUE of
;;; the constant. If you don't want that to happen, you should
-;;; probably use DEFPARAMETER instead.
+;;; probably use DEFPARAMETER instead; or if you truly desperately
+;;; need to avoid runtime indirection through a symbol, you might be
+;;; able to do something with LOAD-TIME-VALUE or MAKE-LOAD-FORM.
(defmacro defconstant-eqx (symbol expr eqx &optional doc)
- (let ((expr-tmp (gensym "EXPR-TMP-")))
- `(progn
- ;; When we're building the cross-compiler, and in most
- ;; situations even when we're running the cross-compiler,
- ;; all we need is a nice portable definition in terms of the
- ;; ANSI Common Lisp operations.
- (eval-when (:compile-toplevel :load-toplevel :execute)
- (let ((,expr-tmp ,expr))
- (cond ((boundp ',symbol)
- (unless (and (constantp ',symbol)
- (funcall ,eqx
- (symbol-value ',symbol)
- ,expr-tmp))
- (error "already bound differently: ~S")))
- (t
- (defconstant ,symbol
- ;; KLUDGE: This is a very ugly hack, to be able to
- ;; build SBCL with CMU CL (2.4.19), because there
- ;; seems to be some confusion in CMU CL about
- ;; ,EXPR-TEMP at EVAL-WHEN time ... -- MNA 2000-02-23
- #-cmu ,expr-tmp
- #+cmu ,expr
- ,@(when doc `(,doc)))))))
- ;; The #+SB-XC :COMPILE-TOPLEVEL situation is special, since we
- ;; want to define the symbol not just in the cross-compilation
- ;; host Lisp (which was handled above) but also in the
- ;; cross-compiler (which we will handle now).
- ;;
- ;; KLUDGE: It would probably be possible to do this fairly
- ;; cleanly, in a way parallel to the code above, if we had
- ;; SB!XC:FOO versions of all the primitives CL:FOO used above
- ;; (e.g. SB!XC:BOUNDP, SB!XC:SYMBOL-VALUE, and
- ;; SB!XC:DEFCONSTANT), and took care to call them. But right
- ;; now we just hack around in the guts of the cross-compiler
- ;; instead. -- WHN 2000-11-03
- #+sb-xc
- (eval-when (:compile-toplevel)
- (let ((,expr-tmp ,symbol))
- (unless (and (eql (info :variable :kind ',symbol) :constant)
- (funcall ,eqx
- (info :variable :constant-value ',symbol)
- ,expr-tmp))
- (sb!c::%defconstant ',symbol ,expr-tmp ,doc)))))))
+ `(def!constant ,symbol
+ (%defconstant-eqx-value ',symbol ,expr ,eqx)
+ ,@(when doc (list doc))))
+(defun %defconstant-eqx-value (symbol expr eqx)
+ (declare (type function eqx))
+ (flet ((bummer (explanation)
+ (error "~@<bad DEFCONSTANT-EQX ~S ~2I~_~S: ~2I~_~A ~S~:>"
+ symbol
+ expr
+ explanation
+ (symbol-value symbol))))
+ (cond ((not (boundp symbol))
+ expr)
+ ((not (constantp symbol))
+ (bummer "already bound as a non-constant"))
+ ((not (funcall eqx (symbol-value symbol) expr))
+ (bummer "already bound as a different constant value"))
+ (t
+ (symbol-value symbol)))))
+\f
+;;; a helper function for various macros which expect clauses of a
+;;; given length, etc.
+;;;
+;;; Return true if X is a proper list whose length is between MIN and
+;;; MAX (inclusive).
+(defun proper-list-of-length-p (x min &optional (max min))
+ ;; FIXME: This implementation will hang on circular list
+ ;; structure. Since this is an error-checking utility, i.e. its
+ ;; job is to deal with screwed-up input, it'd be good style to fix
+ ;; it so that it can deal with circular list structure.
+ (cond ((minusp max) nil)
+ ((null x) (zerop min))
+ ((consp x)
+ (and (plusp max)
+ (proper-list-of-length-p (cdr x)
+ (if (plusp (1- min))
+ (1- min)
+ 0)
+ (1- max))))
+ (t nil)))