src/code/condition.lisp

   1 ;;;; stuff originally from CMU CL's error.lisp which can or should
   2 ;;;; come late (mostly related to the CONDITION class itself)
   3 ;;;;
   4
   5 ;;;; This software is part of the SBCL system. See the README file for
   6 ;;;; more information.
   7 ;;;;
   8 ;;;; This software is derived from the CMU CL system, which was
   9 ;;;; written at Carnegie Mellon University and released into the
  10 ;;;; public domain. The software is in the public domain and is
  11 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
  12 ;;;; files for more information.
  13
  14 (in-package "SB!KERNEL")
  15 \f
  16 ;;;; the CONDITION class
  17
  18 (/show0 "condition.lisp 20")
  19
  20 (defstruct (condition-slot (:copier nil))
  21   (name (missing-arg) :type symbol)
  22   ;; list of all applicable initargs
  23   (initargs (missing-arg) :type list)
  24   ;; names of reader and writer functions
  25   (readers (missing-arg) :type list)
  26   (writers (missing-arg) :type list)
  27   ;; true if :INITFORM was specified
  28   (initform-p (missing-arg) :type (member t nil))
  29   ;; the initform if :INITFORM was specified, otherwise NIL
  30   (initform nil :type t)
  31   ;; if this is a function, call it with no args to get the initform value
  32   (initfunction (missing-arg) :type t)
  33   ;; allocation of this slot, or NIL until defaulted
  34   (allocation nil :type (member :instance :class nil))
  35   ;; If ALLOCATION is :CLASS, this is a cons whose car holds the value
  36   (cell nil :type (or cons null))
  37   ;; slot documentation
  38   (documentation nil :type (or string null)))
  39
  40 ;;; KLUDGE: It's not clear to me why CONDITION-CLASS has itself listed
  41 ;;; in its CPL, while other classes derived from CONDITION-CLASS don't
  42 ;;; have themselves listed in their CPLs. This behavior is inherited
  43 ;;; from CMU CL, and didn't seem to be explained there, and I haven't
  44 ;;; figured out whether it's right. -- WHN 19990612
  45 (eval-when (:compile-toplevel :load-toplevel :execute)
  46   (/show0 "condition.lisp 103")
  47   (let ((condition-class (find-classoid 'condition)))
  48     (setf (condition-classoid-cpl condition-class)
  49           (list condition-class)))
  50   (/show0 "condition.lisp 103"))
  51
  52 (setf (condition-classoid-report (find-classoid 'condition))
  53       (lambda (cond stream)
  54         (format stream "Condition ~S was signalled." (type-of cond))))
  55
  56 (eval-when (:compile-toplevel :load-toplevel :execute)
  57
  58 (defun find-condition-layout (name parent-types)
  59   (let* ((cpl (remove-duplicates
  60                (reverse
  61                 (reduce #'append
  62                         (mapcar (lambda (x)
  63                                   (condition-classoid-cpl
  64                                    (find-classoid x)))
  65                                 parent-types)))))
  66          (cond-layout (info :type :compiler-layout 'condition))
  67          (olayout (info :type :compiler-layout name))
  68          ;; FIXME: Does this do the right thing in case of multiple
  69          ;; inheritance? A quick look at DEFINE-CONDITION didn't make
  70          ;; it obvious what ANSI intends to be done in the case of
  71          ;; multiple inheritance, so it's not actually clear what the
  72          ;; right thing is..
  73          (new-inherits
  74           (order-layout-inherits (concatenate 'simple-vector
  75                                               (layout-inherits cond-layout)
  76                                               (mapcar #'classoid-layout cpl)))))
  77     (if (and olayout
  78              (not (mismatch (layout-inherits olayout) new-inherits)))
  79         olayout
  80         (make-layout :classoid (make-undefined-classoid name)
  81                      :inherits new-inherits
  82                      :depthoid -1
  83                      :length (layout-length cond-layout)))))
  84
  85 ) ; EVAL-WHEN
  86
  87 ;;; FIXME: ANSI's definition of DEFINE-CONDITION says
  88 ;;;   Condition reporting is mediated through the PRINT-OBJECT method
  89 ;;;   for the condition type in question, with *PRINT-ESCAPE* always
  90 ;;;   being nil. Specifying (:REPORT REPORT-NAME) in the definition of
  91 ;;;   a condition type C is equivalent to:
  92 ;;;     (defmethod print-object ((x c) stream)
  93 ;;;       (if *print-escape* (call-next-method) (report-name x stream)))
  94 ;;; The current code doesn't seem to quite match that.
  95 (def*method print-object ((x condition) stream)
  96   (if *print-escape*
  97       (if (and (typep x 'simple-condition) (slot-value x 'format-control))
  98           (print-unreadable-object (x stream :type t :identity t)
  99             (write (simple-condition-format-control x)
 100                    :stream stream
 101                    :lines 1))
 102           (print-unreadable-object (x stream :type t :identity t)))
 103       ;; KLUDGE: A comment from CMU CL here said
 104       ;;   7/13/98 BUG? CPL is not sorted and results here depend on order of
 105       ;;   superclasses in define-condition call!
 106       (dolist (class (condition-classoid-cpl (classoid-of x))
 107                      (error "no REPORT? shouldn't happen!"))
 108         (let ((report (condition-classoid-report class)))
 109           (when report
 110             (return (funcall report x stream)))))))
 111
 112 ;;; It is essential that there be a method that works in warm load
 113 ;;; because any conditions signaled are not printable otherwise,
 114 ;;; except by the method on type T which is completely unhelpful.
 115 (defmethod print-object ((x condition) stream)
 116   (print-unreadable-object (x stream :type t :identity t)
 117     (write (%instance-ref x 1) :stream stream :escape t)))
 118 \f
 119 ;;;; slots of CONDITION objects
 120
 121 (defvar *empty-condition-slot* '(empty))
 122
 123 (defun find-slot-default (class slot)
 124   (let ((initargs (condition-slot-initargs slot))
 125         (cpl (condition-classoid-cpl class)))
 126     ;; When CLASS or a superclass has a default initarg for SLOT, use
 127     ;; that.
 128     (dolist (class cpl)
 129       (let ((direct-default-initargs
 130               (condition-classoid-direct-default-initargs class)))
 131         (dolist (initarg initargs)
 132           (let ((initfunction (third (assoc initarg direct-default-initargs))))
 133             (when initfunction
 134               (return-from find-slot-default (funcall initfunction)))))))
 135
 136     ;; Otherwise use the initform of SLOT, if there is one.
 137     (if (condition-slot-initform-p slot)
 138         (let ((initfun (condition-slot-initfunction slot)))
 139           (aver (functionp initfun))
 140           (funcall initfun))
 141         (error "unbound condition slot: ~S" (condition-slot-name slot)))))
 142
 143 (defun find-condition-class-slot (condition-class slot-name)
 144   (dolist (sclass
 145            (condition-classoid-cpl condition-class)
 146            (error "There is no slot named ~S in ~S."
 147                   slot-name condition-class))
 148     (dolist (slot (condition-classoid-slots sclass))
 149       (when (eq (condition-slot-name slot) slot-name)
 150         (return-from find-condition-class-slot slot)))))
 151
 152 (defun condition-writer-function (condition new-value name)
 153   (dolist (cslot (condition-classoid-class-slots
 154                   (layout-classoid (%instance-layout condition)))
 155                  (setf (getf (condition-assigned-slots condition) name)
 156                        new-value))
 157     (when (eq (condition-slot-name cslot) name)
 158       (return (setf (car (condition-slot-cell cslot)) new-value)))))
 159
 160 (defun condition-reader-function (condition name)
 161   (let ((class (layout-classoid (%instance-layout condition))))
 162     (dolist (cslot (condition-classoid-class-slots class))
 163       (when (eq (condition-slot-name cslot) name)
 164         (return-from condition-reader-function
 165                      (car (condition-slot-cell cslot)))))
 166     (let ((val (getf (condition-assigned-slots condition) name
 167                      *empty-condition-slot*)))
 168       (if (eq val *empty-condition-slot*)
 169           (let ((actual-initargs (condition-actual-initargs condition))
 170                 (slot (find-condition-class-slot class name)))
 171             (unless slot
 172               (error "missing slot ~S of ~S" name condition))
 173             (do ((initargs actual-initargs (cddr initargs)))
 174                 ((endp initargs)
 175                  (setf (getf (condition-assigned-slots condition) name)
 176                        (find-slot-default class slot)))
 177               (when (member (car initargs) (condition-slot-initargs slot))
 178                 (return-from condition-reader-function
 179                   (setf (getf (condition-assigned-slots condition)
 180                               name)
 181                         (cadr initargs))))))
 182           val))))
 183 \f
 184 ;;;; MAKE-CONDITION
 185
 186 (defun allocate-condition (designator &rest initargs)
 187   ;; I am going to assume that people are not somehow getting to here
 188   ;; with a CLASSOID, which is not strictly legal as a designator,
 189   ;; but which is accepted because it is actually the desired thing.
 190   ;; It doesn't seem worth sweating over that detail, and in any event
 191   ;; we could say that it's a supported extension.
 192   (let ((classoid (named-let lookup ((designator designator))
 193                     (typecase designator
 194                      (symbol (find-classoid designator nil))
 195                      (class (lookup (class-name designator)))
 196                      (t designator)))))
 197     (if (condition-classoid-p classoid)
 198         (let ((instance (%make-condition-object initargs '())))
 199           (setf (%instance-layout instance) (classoid-layout classoid))
 200           (values instance classoid))
 201         (error 'simple-type-error
 202                :datum designator
 203                ;; CONDITION-CLASS isn't a type-specifier. Is this legal?
 204                :expected-type 'condition-class
 205                :format-control "~S does not designate a condition class."
 206                :format-arguments (list designator)))))
 207
 208 (defun make-condition (type &rest initargs)
 209   #!+sb-doc
 210   "Make an instance of a condition object using the specified initargs."
 211   ;; Note: While ANSI specifies no exceptional situations in this function,
 212   ;; ALLOCATE-CONDITION will signal a type error if TYPE does not designate
 213   ;; a condition class. This seems fair enough.
 214   (declare (explicit-check))
 215   (multiple-value-bind (condition classoid)
 216       (apply #'allocate-condition type initargs)
 217
 218     ;; Set any class slots with initargs present in this call.
 219     (dolist (cslot (condition-classoid-class-slots classoid))
 220       (dolist (initarg (condition-slot-initargs cslot))
 221         (let ((val (getf initargs initarg *empty-condition-slot*)))
 222           (unless (eq val *empty-condition-slot*)
 223             (setf (car (condition-slot-cell cslot)) val)))))
 224
 225     ;; Default any slots with non-constant defaults now.
 226     (dolist (hslot (condition-classoid-hairy-slots classoid))
 227       (when (dolist (initarg (condition-slot-initargs hslot) t)
 228               (unless (eq (getf initargs initarg *empty-condition-slot*)
 229                           *empty-condition-slot*)
 230                 (return nil)))
 231         (setf (getf (condition-assigned-slots condition)
 232                     (condition-slot-name hslot))
 233               (find-slot-default classoid hslot))))
 234
 235     condition))
 236
 237 \f
 238 ;;;; DEFINE-CONDITION
 239
 240 ;;; Compute the effective slots of CLASS, copying inherited slots and
 241 ;;; destructively modifying direct slots.
 242 ;;;
 243 ;;; FIXME: It'd be nice to explain why it's OK to destructively modify
 244 ;;; direct slots. Presumably it follows from the semantics of
 245 ;;; inheritance and redefinition of conditions, but finding the cite
 246 ;;; and documenting it here would be good. (Or, if this is not in fact
 247 ;;; ANSI-compliant, fixing it would also be good.:-)
 248 (defun compute-effective-slots (class)
 249   (collect ((res (copy-list (condition-classoid-slots class))))
 250     (dolist (sclass (cdr (condition-classoid-cpl class)))
 251       (dolist (sslot (condition-classoid-slots sclass))
 252         (let ((found (find (condition-slot-name sslot) (res)
 253                            :key #'condition-slot-name)))
 254           (cond (found
 255                  (setf (condition-slot-initargs found)
 256                        (union (condition-slot-initargs found)
 257                               (condition-slot-initargs sslot)))
 258                  (unless (condition-slot-initform-p found)
 259                    (setf (condition-slot-initform-p found)
 260                          (condition-slot-initform-p sslot))
 261                    (setf (condition-slot-initform found)
 262                          (condition-slot-initform sslot))
 263                    (setf (condition-slot-initfunction found)
 264                          (condition-slot-initfunction sslot)))
 265                  (unless (condition-slot-allocation found)
 266                    (setf (condition-slot-allocation found)
 267                          (condition-slot-allocation sslot))))
 268                 (t
 269                  (res (copy-structure sslot)))))))
 270     (res)))
 271
 272 ;;; Early definitions of slot accessor creators.
 273 ;;;
 274 ;;; Slot accessors must be generic functions, but ANSI does not seem
 275 ;;; to specify any of them, and we cannot support it before end of
 276 ;;; warm init. So we use ordinary functions inside SBCL, and switch to
 277 ;;; GFs only at the end of building.
 278 (declaim (notinline install-condition-slot-reader
 279                     install-condition-slot-writer))
 280 (defun install-condition-slot-reader (name condition slot-name)
 281   (declare (ignore condition))
 282   (setf (fdefinition name)
 283         (lambda (condition)
 284           (condition-reader-function condition slot-name))))
 285 (defun install-condition-slot-writer (name condition slot-name)
 286   (declare (ignore condition))
 287   (setf (fdefinition name)
 288         (lambda (new-value condition)
 289           (condition-writer-function condition new-value slot-name))))
 290
 291 (!defvar *define-condition-hooks* nil)
 292
 293 (defun %set-condition-report (name report)
 294   (setf (condition-classoid-report (find-classoid name))
 295         report))
 296
 297 (defun %define-condition (name parent-types layout slots
 298                           direct-default-initargs all-readers all-writers
 299                           source-location &optional documentation)
 300   (with-single-package-locked-error
 301       (:symbol name "defining ~A as a condition")
 302     (%compiler-define-condition name parent-types layout all-readers all-writers)
 303     (when source-location
 304       (setf (layout-source-location layout) source-location))
 305     (let ((class (find-classoid name))) ; FIXME: rename to 'classoid'
 306       (setf (condition-classoid-slots class) slots
 307             (condition-classoid-direct-default-initargs class) direct-default-initargs
 308             (fdocumentation name 'type) documentation)
 309
 310       (dolist (slot slots)
 311
 312         ;; Set up reader and writer functions.
 313         (let ((slot-name (condition-slot-name slot)))
 314           (dolist (reader (condition-slot-readers slot))
 315             (install-condition-slot-reader reader name slot-name))
 316           (dolist (writer (condition-slot-writers slot))
 317             (install-condition-slot-writer writer name slot-name))))
 318
 319       ;; Compute effective slots and set up the class and hairy slots
 320       ;; (subsets of the effective slots.)
 321       (setf (condition-classoid-class-slots class) '()
 322             (condition-classoid-hairy-slots class) '())
 323       (let ((eslots (compute-effective-slots class))
 324             (e-def-initargs
 325              (reduce #'append
 326                      (mapcar #'condition-classoid-direct-default-initargs
 327                              (condition-classoid-cpl class)))))
 328         (dolist (slot eslots)
 329           (ecase (condition-slot-allocation slot)
 330             (:class
 331              (unless (condition-slot-cell slot)
 332                (setf (condition-slot-cell slot)
 333                      (list (if (condition-slot-initform-p slot)
 334                                (let ((initfun (condition-slot-initfunction slot)))
 335                                  (aver (functionp initfun))
 336                                  (funcall initfun))
 337                                *empty-condition-slot*))))
 338              (push slot (condition-classoid-class-slots class)))
 339             ((:instance nil)
 340              (setf (condition-slot-allocation slot) :instance)
 341              ;; FIXME: isn't this "always hairy"?
 342              (when (or (functionp (condition-slot-initfunction slot))
 343                        (dolist (initarg (condition-slot-initargs slot) nil)
 344                          (when (functionp (third (assoc initarg e-def-initargs)))
 345                            (return t))))
 346                (push slot (condition-classoid-hairy-slots class)))))))
 347       (dolist (fun *define-condition-hooks*)
 348         (funcall fun class)))
 349     name))
 350
 351 (defmacro define-condition (name (&rest parent-types) (&rest slot-specs)
 352                                  &body options)
 353   #!+sb-doc
 354   "DEFINE-CONDITION Name (Parent-Type*) (Slot-Spec*) Option*
 355    Define NAME as a condition type. This new type inherits slots and its
 356    report function from the specified PARENT-TYPEs. A slot spec is a list of:
 357      (slot-name :reader <rname> :initarg <iname> {Option Value}*
 358
 359    The DEFINE-CLASS slot options :ALLOCATION, :INITFORM, [slot] :DOCUMENTATION
 360    and :TYPE and the overall options :DEFAULT-INITARGS and
 361    [type] :DOCUMENTATION are also allowed.
 362
 363    The :REPORT option is peculiar to DEFINE-CONDITION. Its argument is either
 364    a string or a two-argument lambda or function name. If a function, the
 365    function is called with the condition and stream to report the condition.
 366    If a string, the string is printed.
 367
 368    Condition types are classes, but (as allowed by ANSI and not as described in
 369    CLtL2) are neither STANDARD-OBJECTs nor STRUCTURE-OBJECTs. WITH-SLOTS and
 370    SLOT-VALUE may not be used on condition objects."
 371   (let* ((parent-types (or parent-types '(condition)))
 372          (layout (find-condition-layout name parent-types))
 373          (documentation nil)
 374          (report nil)
 375          (direct-default-initargs ()))
 376     (collect ((slots)
 377               (all-readers nil append)
 378               (all-writers nil append))
 379       (dolist (spec slot-specs)
 380         (when (keywordp spec)
 381           (warn "Keyword slot name indicates probable syntax error:~%  ~S"
 382                 spec))
 383         (let* ((spec (if (consp spec) spec (list spec)))
 384                (slot-name (first spec))
 385                (allocation :instance)
 386                (initform-p nil)
 387                documentation
 388                initform)
 389           (collect ((initargs)
 390                     (readers)
 391                     (writers))
 392             (do ((options (rest spec) (cddr options)))
 393                 ((null options))
 394               (unless (and (consp options) (consp (cdr options)))
 395                 (error "malformed condition slot spec:~%  ~S." spec))
 396               (let ((arg (second options)))
 397                 (case (first options)
 398                   (:reader (readers arg))
 399                   (:writer (writers arg))
 400                   (:accessor
 401                    (readers arg)
 402                    (writers `(setf ,arg)))
 403                   (:initform
 404                    (when initform-p
 405                      (error "more than one :INITFORM in ~S" spec))
 406                    (setq initform-p t)
 407                    (setq initform arg))
 408                   (:initarg (initargs arg))
 409                   (:allocation
 410                    (setq allocation arg))
 411                   (:documentation
 412                    (when documentation
 413                      (error "more than one :DOCUMENTATION in ~S" spec))
 414                    (unless (stringp arg)
 415                      (error "slot :DOCUMENTATION argument is not a string: ~S"
 416                             arg))
 417                    (setq documentation arg))
 418                   (:type)
 419                   (t
 420                    (error "unknown slot option:~%  ~S" (first options))))))
 421
 422             (all-readers (readers))
 423             (all-writers (writers))
 424             (slots `(make-condition-slot
 425                      :name ',slot-name
 426                      :initargs ',(initargs)
 427                      :readers ',(readers)
 428                      :writers ',(writers)
 429                      :initform-p ',initform-p
 430                      :documentation ',documentation
 431                      :initform ,(when initform-p `',initform)
 432                      :initfunction ,(when initform-p
 433                                       `#'(lambda () ,initform))
 434                      :allocation ',allocation)))))
 435
 436       (dolist (option options)
 437         (unless (consp option)
 438           (error "bad option:~%  ~S" option))
 439         (case (first option)
 440           (:documentation (setq documentation (second option)))
 441           (:report
 442            (let ((arg (second option)))
 443              (setq report
 444                    `#'(named-lambda (condition-report ,name) (condition stream)
 445                         ,@(if (stringp arg)
 446                               `((declare (ignore condition))
 447                                 (write-string ,arg stream))
 448                               `((funcall #',arg condition stream)))))))
 449           (:default-initargs
 450            (doplist (initarg initform) (rest option)
 451              (push ``(,',initarg ,',initform ,#'(lambda () ,initform))
 452                    direct-default-initargs)))
 453           (t
 454            (error "unknown option: ~S" (first option)))))
 455
 456       `(progn
 457          (eval-when (:compile-toplevel)
 458            (%compiler-define-condition ',name ',parent-types ',layout
 459                                        ',(all-readers) ',(all-writers)))
 460          (%define-condition ',name
 461                             ',parent-types
 462                             ',layout
 463                             (list ,@(slots))
 464                             (list ,@direct-default-initargs)
 465                             ',(all-readers)
 466                             ',(all-writers)
 467                             (sb!c:source-location)
 468                             ,@(and documentation
 469                                    `(,documentation)))
 470          ;; This needs to be after %DEFINE-CONDITION in case :REPORT
 471          ;; is a lambda referring to condition slot accessors:
 472          ;; they're not proclaimed as functions before it has run if
 473          ;; we're under EVAL or loaded as source.
 474          (%set-condition-report ',name ,report)
 475          ',name))))
 476 \f
 477 ;;;; various CONDITIONs specified by ANSI
 478
 479 (define-condition serious-condition (condition) ())
 480
 481 (define-condition error (serious-condition) ())
 482
 483 (define-condition warning (condition) ())
 484 (define-condition style-warning (warning) ())
 485
 486 (defun simple-condition-printer (condition stream)
 487   (let ((control (simple-condition-format-control condition)))
 488     (if control
 489         (apply #'format stream
 490                control
 491                (simple-condition-format-arguments condition))
 492         (error "No format-control for ~S" condition))))
 493
 494 (define-condition simple-condition ()
 495   ((format-control :reader simple-condition-format-control
 496                    :initarg :format-control
 497                    :initform nil
 498                    :type format-control)
 499    (format-arguments :reader simple-condition-format-arguments
 500                      :initarg :format-arguments
 501                      :initform nil
 502                      :type list))
 503   (:report simple-condition-printer))
 504
 505 (define-condition simple-warning (simple-condition warning) ())
 506
 507 (define-condition simple-error (simple-condition error) ())
 508
 509 (define-condition storage-condition (serious-condition) ())
 510
 511 (define-condition type-error (error)
 512   ((datum :reader type-error-datum :initarg :datum)
 513    (expected-type :reader type-error-expected-type :initarg :expected-type))
 514   (:report
 515    (lambda (condition stream)
 516      (format stream
 517              "~@<The value ~2I~:_~S ~I~_is not of type ~2I~_~S.~:>"
 518              (type-error-datum condition)
 519              (type-error-expected-type condition)))))
 520
 521 (def*method print-object ((condition type-error) stream)
 522   (if (and *print-escape*
 523            (slot-boundp condition 'expected-type)
 524            (slot-boundp condition 'datum))
 525       (flet ((maybe-string (thing)
 526                (ignore-errors
 527                  (write-to-string thing :lines 1 :readably nil :array nil :pretty t))))
 528         (let ((type (maybe-string (type-error-expected-type condition)))
 529               (datum (maybe-string (type-error-datum condition))))
 530           (if (and type datum)
 531               (print-unreadable-object (condition stream :type t)
 532                 (format stream "~@<expected-type: ~A ~_datum: ~A~:@>" type datum))
 533               (call-next-method))))
 534       (call-next-method)))
 535
 536 ;;; not specified by ANSI, but too useful not to have around.
 537 (define-condition simple-style-warning (simple-condition style-warning) ())
 538 (define-condition simple-type-error (simple-condition type-error) ())
 539
 540 (define-condition program-error (error) ())
 541 (define-condition parse-error   (error) ())
 542 (define-condition control-error (error) ())
 543 (define-condition stream-error  (error)
 544   ((stream :reader stream-error-stream :initarg :stream)))
 545
 546 (define-condition end-of-file (stream-error) ()
 547   (:report
 548    (lambda (condition stream)
 549      (format stream
 550              "end of file on ~S"
 551              (stream-error-stream condition)))))
 552
 553 (define-condition closed-stream-error (stream-error) ()
 554   (:report
 555    (lambda (condition stream)
 556      (format stream "~S is closed" (stream-error-stream condition)))))
 557
 558 (define-condition file-error (error)
 559   ((pathname :reader file-error-pathname :initarg :pathname))
 560   (:report
 561    (lambda (condition stream)
 562      (format stream "error on file ~S" (file-error-pathname condition)))))
 563
 564 (define-condition package-error (error)
 565   ((package :reader package-error-package :initarg :package)))
 566
 567 (define-condition cell-error (error)
 568   ((name :reader cell-error-name :initarg :name)))
 569
 570 (def*method print-object ((condition cell-error) stream)
 571   (if (and *print-escape* (slot-boundp condition 'name))
 572       (print-unreadable-object (condition stream :type t :identity t)
 573         (princ (cell-error-name condition) stream))
 574       (call-next-method)))
 575
 576 (define-condition unbound-variable (cell-error) ()
 577   (:report
 578    (lambda (condition stream)
 579      (format stream
 580              "The variable ~S is unbound."
 581              (cell-error-name condition)))))
 582
 583 (define-condition undefined-function (cell-error) ()
 584   (:report
 585    (lambda (condition stream)
 586      (let ((*package* (find-package :keyword)))
 587        (format stream
 588                "The function ~S is undefined."
 589                (cell-error-name condition))))))
 590
 591 (define-condition special-form-function (undefined-function) ()
 592   (:report
 593    (lambda (condition stream)
 594      (format stream
 595              "Cannot FUNCALL the SYMBOL-FUNCTION of special operator ~S."
 596              (cell-error-name condition)))))
 597
 598 (define-condition arithmetic-error (error)
 599   ((operation :reader arithmetic-error-operation
 600               :initarg :operation
 601               :initform nil)
 602    (operands :reader arithmetic-error-operands
 603              :initarg :operands))
 604   (:report (lambda (condition stream)
 605              (format stream
 606                      "arithmetic error ~S signalled"
 607                      (type-of condition))
 608              (when (arithmetic-error-operation condition)
 609                (format stream
 610                        "~%Operation was ~S, operands ~S."
 611                        (arithmetic-error-operation condition)
 612                        (arithmetic-error-operands condition))))))
 613
 614 (define-condition division-by-zero         (arithmetic-error) ())
 615 (define-condition floating-point-overflow  (arithmetic-error) ())
 616 (define-condition floating-point-underflow (arithmetic-error) ())
 617 (define-condition floating-point-inexact   (arithmetic-error) ())
 618 (define-condition floating-point-invalid-operation (arithmetic-error) ())
 619
 620 (define-condition print-not-readable (error)
 621   ((object :reader print-not-readable-object :initarg :object))
 622   (:report
 623    (lambda (condition stream)
 624      (let ((obj (print-not-readable-object condition))
 625            (*print-array* nil))
 626        (format stream "~S cannot be printed readably." obj)))))
 627
 628 (define-condition reader-error (parse-error stream-error) ()
 629   (:report (lambda (condition stream)
 630              (%report-reader-error condition stream))))
 631
 632 ;;; a READER-ERROR whose REPORTing is controlled by FORMAT-CONTROL and
 633 ;;; FORMAT-ARGS (the usual case for READER-ERRORs signalled from
 634 ;;; within SBCL itself)
 635 ;;;
 636 ;;; (Inheriting CL:SIMPLE-CONDITION here isn't quite consistent with
 637 ;;; the letter of the ANSI spec: this is not a condition signalled by
 638 ;;; SIGNAL when a format-control is supplied by the function's first
 639 ;;; argument. It seems to me (WHN) to be basically in the spirit of
 640 ;;; the spec, but if not, it'd be straightforward to do our own
 641 ;;; DEFINE-CONDITION SB-INT:SIMPLISTIC-CONDITION with
 642 ;;; FORMAT-CONTROL and FORMAT-ARGS slots, and use that condition in
 643 ;;; place of CL:SIMPLE-CONDITION here.)
 644 (define-condition simple-reader-error (reader-error simple-condition)
 645   ()
 646   (:report (lambda (condition stream)
 647              (%report-reader-error condition stream :simple t))))
 648
 649 ;;; base REPORTing of a READER-ERROR
 650 ;;;
 651 ;;; When SIMPLE, we expect and use SIMPLE-CONDITION-ish FORMAT-CONTROL
 652 ;;; and FORMAT-ARGS slots.
 653 (defun %report-reader-error (condition stream &key simple position)
 654   (let ((error-stream (stream-error-stream condition)))
 655     (pprint-logical-block (stream nil)
 656       (if simple
 657           (apply #'format stream
 658                  (simple-condition-format-control condition)
 659                  (simple-condition-format-arguments condition))
 660           (prin1 (class-name (class-of condition)) stream))
 661       (format stream "~2I~@[~_~_~:{~:(~A~): ~S~:^, ~:_~}~]~_~_Stream: ~S"
 662               (stream-error-position-info error-stream position)
 663               error-stream))))
 664 \f
 665 ;;;; special SBCL extension conditions
 666
 667 ;;; an error apparently caused by a bug in SBCL itself
 668 ;;;
 669 ;;; Note that we don't make any serious effort to use this condition
 670 ;;; for *all* errors in SBCL itself. E.g. type errors and array
 671 ;;; indexing errors can occur in functions called from SBCL code, and
 672 ;;; will just end up as ordinary TYPE-ERROR or invalid index error,
 673 ;;; because the signalling code has no good way to know that the
 674 ;;; underlying problem is a bug in SBCL. But in the fairly common case
 675 ;;; that the signalling code does know that it's found a bug in SBCL,
 676 ;;; this condition is appropriate, reusing boilerplate and helping
 677 ;;; users to recognize it as an SBCL bug.
 678 (define-condition bug (simple-error)
 679   ()
 680   (:report
 681    (lambda (condition stream)
 682      (format stream
 683              "~@<  ~? ~:@_~?~:>"
 684              (simple-condition-format-control condition)
 685              (simple-condition-format-arguments condition)
 686              "~@<This is probably a bug in SBCL itself. (Alternatively, ~
 687               SBCL might have been corrupted by bad user code, e.g. by an ~
 688               undefined Lisp operation like ~S, or by stray pointers from ~
 689               alien code or from unsafe Lisp code; or there might be a bug ~
 690               in the OS or hardware that SBCL is running on.) If it seems to ~
 691               be a bug in SBCL itself, the maintainers would like to know ~
 692               about it. Bug reports are welcome on the SBCL ~
 693               mailing lists, which you can find at ~
 694               <http://sbcl.sourceforge.net/>.~:@>"
 695              '((fmakunbound 'compile))))))
 696
 697 (define-condition simple-storage-condition (storage-condition simple-condition)
 698   ())
 699
 700 ;;; a condition for use in stubs for operations which aren't supported
 701 ;;; on some platforms
 702 ;;;
 703 ;;; E.g. in sbcl-0.7.0.5, it might be appropriate to do something like
 704 ;;;   #-(or freebsd linux)
 705 ;;;   (defun load-foreign (&rest rest)
 706 ;;;     (error 'unsupported-operator :name 'load-foreign))
 707 ;;;   #+(or freebsd linux)
 708 ;;;   (defun load-foreign ... actual definition ...)
 709 ;;; By signalling a standard condition in this case, we make it
 710 ;;; possible for test code to distinguish between (1) intentionally
 711 ;;; unimplemented and (2) unintentionally just screwed up somehow.
 712 ;;; (Before this condition was defined, test code tried to deal with
 713 ;;; this by checking for FBOUNDP, but that didn't work reliably. In
 714 ;;; sbcl-0.7.0, a package screwup left the definition of
 715 ;;; LOAD-FOREIGN in the wrong package, so it was unFBOUNDP even on
 716 ;;; architectures where it was supposed to be supported, and the
 717 ;;; regression tests cheerfully passed because they assumed that
 718 ;;; unFBOUNDPness meant they were running on an system which didn't
 719 ;;; support the extension.)
 720 (define-condition unsupported-operator (simple-error) ())
 721 \f
 722 ;;; (:ansi-cl :function remove)
 723 ;;; (:ansi-cl :section (a b c))
 724 ;;; (:ansi-cl :glossary "similar")
 725 ;;;
 726 ;;; (:sbcl :node "...")
 727 ;;; (:sbcl :variable *ed-functions*)
 728 ;;;
 729 ;;; FIXME: this is not the right place for this.
 730 (defun print-reference (reference stream)
 731   (ecase (car reference)
 732     (:amop
 733      (format stream "AMOP")
 734      (format stream ", ")
 735      (destructuring-bind (type data) (cdr reference)
 736        (ecase type
 737          (:readers "Readers for ~:(~A~) Metaobjects"
 738                    (substitute #\  #\- (symbol-name data)))
 739          (:initialization
 740           (format stream "Initialization of ~:(~A~) Metaobjects"
 741                   (substitute #\  #\- (symbol-name data))))
 742          (:generic-function (format stream "Generic Function ~S" data))
 743          (:function (format stream "Function ~S" data))
 744          (:section (format stream "Section ~{~D~^.~}" data)))))
 745     (:ansi-cl
 746      (format stream "The ANSI Standard")
 747      (format stream ", ")
 748      (destructuring-bind (type data) (cdr reference)
 749        (ecase type
 750          (:function (format stream "Function ~S" data))
 751          (:special-operator (format stream "Special Operator ~S" data))
 752          (:macro (format stream "Macro ~S" data))
 753          (:section (format stream "Section ~{~D~^.~}" data))
 754          (:glossary (format stream "Glossary entry for ~S" data))
 755          (:type (format stream "Type ~S" data))
 756          (:system-class (format stream "System Class ~S" data))
 757          (:issue (format stream "writeup for Issue ~A" data)))))
 758     (:sbcl
 759      (format stream "The SBCL Manual")
 760      (format stream ", ")
 761      (destructuring-bind (type data) (cdr reference)
 762        (ecase type
 763          (:node (format stream "Node ~S" data))
 764          (:variable (format stream "Variable ~S" data))
 765          (:function (format stream "Function ~S" data)))))
 766     ;; FIXME: other documents (e.g. CLIM, Franz documentation :-)
 767     ))
 768 (define-condition reference-condition ()
 769   ((references :initarg :references :reader reference-condition-references)))
 770 (defvar *print-condition-references* t)
 771 (def*method print-object :around ((o reference-condition) s)
 772   (call-next-method)
 773   (unless (or *print-escape* *print-readably*)
 774     (when (and *print-condition-references*
 775                (reference-condition-references o))
 776       (format s "~&See also:~%")
 777       (pprint-logical-block (s nil :per-line-prefix "  ")
 778         (do* ((rs (reference-condition-references o) (cdr rs))
 779               (r (car rs) (car rs)))
 780              ((null rs))
 781           (print-reference r s)
 782           (unless (null (cdr rs))
 783             (terpri s)))))))
 784
 785 (define-condition simple-reference-error (reference-condition simple-error)
 786   ())
 787
 788 (define-condition simple-reference-warning (reference-condition simple-warning)
 789   ())
 790
 791 (define-condition arguments-out-of-domain-error
 792     (arithmetic-error reference-condition)
 793   ())
 794
 795 ;; per CLHS: "The consequences are unspecified if functions are ...
 796 ;; multiply defined in the same file." so we are within reason to do any
 797 ;; unspecified behavior at compile-time and/or time, but the compiler was
 798 ;; annoyingly mum about genuinely inadvertent duplicate macro definitions.
 799 ;; Redefinition is henceforth a style-warning, and for compatibility it does
 800 ;; not cause the ERRORP value from COMPILE-TIME to be T.
 801 ;; Nor do we cite section 3.2.2.3 as the governing prohibition.
 802 (defun report-duplicate-definition (condition stream)
 803   (format stream "~@<Duplicate definition for ~S found in  one file.~@:>"
 804           (slot-value condition 'name)))
 805
 806 (define-condition duplicate-definition (reference-condition warning)
 807   ((name :initarg :name :reader duplicate-definition-name))
 808   (:report report-duplicate-definition)
 809   (:default-initargs :references (list '(:ansi-cl :section (3 2 2 3)))))
 810 ;; To my thinking, DUPLICATE-DEFINITION should be the ancestor condition,
 811 ;; and not fatal. But changing the meaning of that concept would be a bad idea,
 812 ;; so instead there is a new condition for the softer variant, which does not
 813 ;; inherit from the former.
 814 (define-condition same-file-redefinition-warning (style-warning)
 815   ;; Slot readers aren't proper generic functions until CLOS is built,
 816   ;; so this doesn't get a reader because you can't pick the same name,
 817   ;; and it wouldn't do any good to pick a different name that nothing knows.
 818   ((name :initarg :name))
 819   (:report report-duplicate-definition))
 820
 821 (define-condition constant-modified (reference-condition warning)
 822   ((fun-name :initarg :fun-name :reader constant-modified-fun-name))
 823   (:report (lambda (c s)
 824              (format s "~@<Destructive function ~S called on ~
 825                         constant data.~@:>"
 826                      (constant-modified-fun-name c))))
 827   (:default-initargs :references (list '(:ansi-cl :special-operator quote)
 828                                        '(:ansi-cl :section (3 2 2 3)))))
 829
 830 (define-condition package-at-variance (reference-condition simple-warning)
 831   ()
 832   (:default-initargs :references (list '(:ansi-cl :macro defpackage)
 833                                        '(:sbcl :variable *on-package-variance*))))
 834
 835 (define-condition package-at-variance-error (reference-condition simple-condition
 836                                              package-error)
 837   ()
 838   (:default-initargs :references (list '(:ansi-cl :macro defpackage))))
 839
 840 (define-condition defconstant-uneql (reference-condition error)
 841   ((name :initarg :name :reader defconstant-uneql-name)
 842    (old-value :initarg :old-value :reader defconstant-uneql-old-value)
 843    (new-value :initarg :new-value :reader defconstant-uneql-new-value))
 844   (:report
 845    (lambda (condition stream)
 846      (format stream
 847              "~@<The constant ~S is being redefined (from ~S to ~S)~@:>"
 848              (defconstant-uneql-name condition)
 849              (defconstant-uneql-old-value condition)
 850              (defconstant-uneql-new-value condition))))
 851   (:default-initargs :references (list '(:ansi-cl :macro defconstant)
 852                                        '(:sbcl :node "Idiosyncrasies"))))
 853
 854 (define-condition array-initial-element-mismatch
 855     (reference-condition simple-warning)
 856   ()
 857   (:default-initargs
 858       :references (list
 859                    '(:ansi-cl :function make-array)
 860                    '(:ansi-cl :function sb!xc:upgraded-array-element-type))))
 861
 862 (define-condition type-warning (reference-condition simple-warning)
 863   ()
 864   (:default-initargs :references (list '(:sbcl :node "Handling of Types"))))
 865 (define-condition type-style-warning (reference-condition simple-style-warning)
 866   ()
 867   (:default-initargs :references (list '(:sbcl :node "Handling of Types"))))
 868
 869 (define-condition local-argument-mismatch (reference-condition simple-warning)
 870   ()
 871   (:default-initargs :references (list '(:ansi-cl :section (3 2 2 3)))))
 872
 873 (define-condition format-args-mismatch (reference-condition)
 874   ()
 875   (:default-initargs :references (list '(:ansi-cl :section (22 3 10 2)))))
 876
 877 (define-condition format-too-few-args-warning
 878     (format-args-mismatch simple-warning)
 879   ())
 880 (define-condition format-too-many-args-warning
 881     (format-args-mismatch simple-style-warning)
 882   ())
 883
 884 (define-condition implicit-generic-function-warning (style-warning)
 885   ((name :initarg :name :reader implicit-generic-function-name))
 886   (:report
 887    (lambda (condition stream)
 888      (format stream "~@<Implicitly creating new generic function ~
 889                      ~/sb-impl::print-symbol-with-prefix/.~:@>"
 890              (implicit-generic-function-name condition)))))
 891
 892 (define-condition extension-failure (reference-condition simple-error)
 893   ())
 894
 895 (define-condition structure-initarg-not-keyword
 896     (reference-condition simple-style-warning)
 897   ()
 898   (:default-initargs :references (list '(:ansi-cl :section (2 4 8 13)))))
 899
 900 #!+sb-package-locks
 901 (progn
 902
 903 (define-condition package-lock-violation (package-error
 904                                           reference-condition
 905                                           simple-condition)
 906   ((current-package :initform *package*
 907                     :reader package-lock-violation-in-package))
 908   (:report
 909    (lambda (condition stream)
 910      (let ((control (simple-condition-format-control condition))
 911            (error-package (package-name
 912                            (package-error-package condition)))
 913            (current-package (package-name
 914                              (package-lock-violation-in-package condition))))
 915        (format stream "~@<Lock on package ~A violated~@[~{ when ~?~}~] ~
 916                        while in package ~A.~:@>"
 917                error-package
 918                (when control
 919                  (list control (simple-condition-format-arguments condition)))
 920                current-package))))
 921   ;; no :default-initargs -- reference-stuff provided by the
 922   ;; signalling form in target-package.lisp
 923   #!+sb-doc
 924   (:documentation
 925    "Subtype of CL:PACKAGE-ERROR. A subtype of this error is signalled
 926 when a package-lock is violated."))
 927
 928 (define-condition package-locked-error (package-lock-violation) ()
 929   #!+sb-doc
 930   (:documentation
 931    "Subtype of SB-EXT:PACKAGE-LOCK-VIOLATION. An error of this type is
 932 signalled when an operation on a package violates a package lock."))
 933
 934 (define-condition symbol-package-locked-error (package-lock-violation)
 935   ((symbol :initarg :symbol :reader package-locked-error-symbol))
 936   #!+sb-doc
 937   (:documentation
 938    "Subtype of SB-EXT:PACKAGE-LOCK-VIOLATION. An error of this type is
 939 signalled when an operation on a symbol violates a package lock. The
 940 symbol that caused the violation is accessed by the function
 941 SB-EXT:PACKAGE-LOCKED-ERROR-SYMBOL."))
 942
 943 ) ; progn
 944
 945 (define-condition undefined-alien-error (cell-error) ()
 946   (:report
 947    (lambda (condition stream)
 948      (if (slot-boundp condition 'name)
 949          (format stream "Undefined alien: ~S" (cell-error-name condition))
 950          (format stream "Undefined alien symbol.")))))
 951
 952 (define-condition undefined-alien-variable-error (undefined-alien-error) ()
 953   (:report
 954    (lambda (condition stream)
 955      (declare (ignore condition))
 956      (format stream "Attempt to access an undefined alien variable."))))
 957
 958 (define-condition undefined-alien-function-error (undefined-alien-error) ()
 959   (:report
 960    (lambda (condition stream)
 961      (if (and (slot-boundp condition 'name)
 962               (cell-error-name condition))
 963          (format stream "The alien function ~s is undefined."
 964                  (cell-error-name condition))
 965          (format stream "Attempt to call an undefined alien function.")))))
 966
 967 \f
 968 ;;;; various other (not specified by ANSI) CONDITIONs
 969 ;;;;
 970 ;;;; These might logically belong in other files; they're here, after
 971 ;;;; setup of CONDITION machinery, only because that makes it easier to
 972 ;;;; get cold init to work.
 973
 974 ;;; OAOOM warning: see cross-condition.lisp
 975 (define-condition encapsulated-condition (condition)
 976   ((condition :initarg :condition :reader encapsulated-condition)))
 977
 978 ;;; KLUDGE: a condition for floating point errors when we can't or
 979 ;;; won't figure out what type they are. (In FreeBSD and OpenBSD we
 980 ;;; don't know how, at least as of sbcl-0.6.7; in Linux we probably
 981 ;;; know how but the old code was broken by the conversion to POSIX
 982 ;;; signal handling and hasn't been fixed as of sbcl-0.6.7.)
 983 ;;;
 984 ;;; FIXME: Perhaps this should also be a base class for all
 985 ;;; floating point exceptions?
 986 (define-condition floating-point-exception (arithmetic-error)
 987   ((flags :initarg :traps
 988           :initform nil
 989           :reader floating-point-exception-traps))
 990   (:report (lambda (condition stream)
 991              (format stream
 992                      "An arithmetic error ~S was signalled.~%"
 993                      (type-of condition))
 994              (let ((traps (floating-point-exception-traps condition)))
 995                (if traps
 996                    (format stream
 997                            "Trapping conditions are: ~%~{ ~S~^~}~%"
 998                            traps)
 999                    (write-line
1000                     "No traps are enabled? How can this be?"
1001                     stream))))))
1002
1003 (define-condition invalid-array-index-error (type-error)
1004   ((array :initarg :array :reader invalid-array-index-error-array)
1005    (axis :initarg :axis :reader invalid-array-index-error-axis))
1006   (:report
1007    (lambda (condition stream)
1008      (let ((array (invalid-array-index-error-array condition)))
1009        (format stream "Invalid index ~W for ~@[axis ~W of ~]~S, ~
1010                        should be a non-negative integer below ~W."
1011                (type-error-datum condition)
1012                (when (> (array-rank array) 1)
1013                  (invalid-array-index-error-axis condition))
1014                (type-of array)
1015                ;; Extract the bound from (INTEGER 0 (BOUND))
1016                (caaddr (type-error-expected-type condition)))))))
1017
1018 (define-condition invalid-array-error (reference-condition type-error) ()
1019   (:report
1020    (lambda (condition stream)
1021      (let ((*print-array* nil))
1022        (format stream
1023                "~@<Displaced array originally of type ~S has been invalidated ~
1024                 due its displaced-to array ~S having become too small to hold ~
1025                 it: the displaced array's dimensions have all been set to zero ~
1026                 to trap accesses to it.~:@>"
1027                (type-error-expected-type condition)
1028                (array-displacement (type-error-datum condition))))))
1029   (:default-initargs
1030       :references
1031       (list '(:ansi-cl :function adjust-array))))
1032
1033 (define-condition index-too-large-error (type-error)
1034   ()
1035   (:report
1036    (lambda (condition stream)
1037      (format stream
1038              "The index ~S is too large."
1039              (type-error-datum condition)))))
1040
1041 (define-condition bounding-indices-bad-error (reference-condition type-error)
1042   ((object :reader bounding-indices-bad-object :initarg :object))
1043   (:report
1044    (lambda (condition stream)
1045      (let* ((datum (type-error-datum condition))
1046             (start (car datum))
1047             (end (cdr datum))
1048             (object (bounding-indices-bad-object condition)))
1049        (etypecase object
1050          (sequence
1051           (format stream
1052                   "The bounding indices ~S and ~S are bad ~
1053                    for a sequence of length ~S."
1054                   start end (length object)))
1055          (array
1056           ;; from WITH-ARRAY-DATA
1057           (format stream
1058                   "The START and END parameters ~S and ~S are ~
1059                    bad for an array of total size ~S."
1060                   start end (array-total-size object)))))))
1061   (:default-initargs
1062       :references
1063       (list '(:ansi-cl :glossary "bounding index designator")
1064             '(:ansi-cl :issue "SUBSEQ-OUT-OF-BOUNDS:IS-AN-ERROR"))))
1065
1066 (define-condition nil-array-accessed-error (reference-condition type-error)
1067   ()
1068   (:report (lambda (condition stream)
1069              (declare (ignore condition))
1070              (format stream
1071                      "An attempt to access an array of element-type ~
1072                       NIL was made.  Congratulations!")))
1073   (:default-initargs
1074       :references (list '(:ansi-cl :function sb!xc:upgraded-array-element-type)
1075                         '(:ansi-cl :section (15 1 2 1))
1076                         '(:ansi-cl :section (15 1 2 2)))))
1077
1078 (define-condition namestring-parse-error (parse-error)
1079   ((complaint :reader namestring-parse-error-complaint :initarg :complaint)
1080    (args :reader namestring-parse-error-args :initarg :args :initform nil)
1081    (namestring :reader namestring-parse-error-namestring :initarg :namestring)
1082    (offset :reader namestring-parse-error-offset :initarg :offset))
1083   (:report
1084    (lambda (condition stream)
1085      (format stream
1086              "parse error in namestring: ~?~%  ~A~%  ~V@T^"
1087              (namestring-parse-error-complaint condition)
1088              (namestring-parse-error-args condition)
1089              (namestring-parse-error-namestring condition)
1090              (namestring-parse-error-offset condition)))))
1091
1092 (define-condition simple-package-error (simple-condition package-error) ())
1093
1094 (define-condition simple-reader-package-error (simple-reader-error package-error) ())
1095
1096 (define-condition reader-eof-error (end-of-file)
1097   ((context :reader reader-eof-error-context :initarg :context))
1098   (:report
1099    (lambda (condition stream)
1100      (format stream
1101              "unexpected end of file on ~S ~A"
1102              (stream-error-stream condition)
1103              (reader-eof-error-context condition)))))
1104
1105 (define-condition reader-impossible-number-error (simple-reader-error)
1106   ((error :reader reader-impossible-number-error-error :initarg :error))
1107   (:report
1108    (lambda (condition stream)
1109      (let ((error-stream (stream-error-stream condition)))
1110        (format stream
1111                "READER-ERROR ~@[at ~W ~]on ~S:~%~?~%Original error: ~A"
1112                (sb!impl::file-position-or-nil-for-error error-stream) error-stream
1113                (simple-condition-format-control condition)
1114                (simple-condition-format-arguments condition)
1115                (reader-impossible-number-error-error condition))))))
1116
1117 (define-condition standard-readtable-modified-error (reference-condition error)
1118   ((operation :initarg :operation :reader standard-readtable-modified-operation))
1119   (:report (lambda (condition stream)
1120              (format stream "~S would modify the standard readtable."
1121                      (standard-readtable-modified-operation condition))))
1122   (:default-initargs :references `((:ansi-cl :section (2 1 1 2))
1123                                    (:ansi-cl :glossary "standard readtable"))))
1124
1125 (define-condition standard-pprint-dispatch-table-modified-error
1126     (reference-condition error)
1127   ((operation :initarg :operation
1128               :reader standard-pprint-dispatch-table-modified-operation))
1129   (:report (lambda (condition stream)
1130              (format stream "~S would modify the standard pprint dispatch table."
1131                      (standard-pprint-dispatch-table-modified-operation
1132                       condition))))
1133   (:default-initargs
1134       :references `((:ansi-cl :glossary "standard pprint dispatch table"))))
1135
1136 (define-condition timeout (serious-condition)
1137   ((seconds :initarg :seconds :initform nil :reader timeout-seconds))
1138   (:report (lambda (condition stream)
1139              (format stream "Timeout occurred~@[ after ~A seconds~]."
1140                      (timeout-seconds condition)))))
1141
1142 (define-condition io-timeout (stream-error timeout)
1143   ((direction :reader io-timeout-direction :initarg :direction))
1144   (:report
1145    (lambda (condition stream)
1146      (declare (type stream stream))
1147      (format stream
1148              "I/O timeout while doing ~(~A~) on ~S."
1149              (io-timeout-direction condition)
1150              (stream-error-stream condition)))))
1151
1152 (define-condition deadline-timeout (timeout) ()
1153   (:report (lambda (condition stream)
1154              (format stream "A deadline was reached after ~A seconds."
1155                      (timeout-seconds condition)))))
1156
1157 (define-condition declaration-type-conflict-error (reference-condition
1158                                                    simple-error)
1159   ()
1160   (:default-initargs
1161       :format-control "symbol ~S cannot be both the name of a type and the name of a declaration"
1162     :references (list '(:ansi-cl :section (3 8 21)))))
1163
1164 ;;; Single stepping conditions
1165
1166 (define-condition step-condition ()
1167   ((form :initarg :form :reader step-condition-form))
1168
1169   #!+sb-doc
1170   (:documentation "Common base class of single-stepping conditions.
1171 STEP-CONDITION-FORM holds a string representation of the form being
1172 stepped."))
1173
1174 #!+sb-doc
1175 (setf (fdocumentation 'step-condition-form 'function)
1176       "Form associated with the STEP-CONDITION.")
1177
1178 (define-condition step-form-condition (step-condition)
1179   ((args :initarg :args :reader step-condition-args))
1180   (:report
1181    (lambda (condition stream)
1182      (let ((*print-circle* t)
1183            (*print-pretty* t)
1184            (*print-readably* nil))
1185        (format stream
1186                  "Evaluating call:~%~<  ~@;~A~:>~%~
1187                   ~:[With arguments:~%~{  ~S~%~}~;With unknown arguments~]~%"
1188                (list (step-condition-form condition))
1189                (eq (step-condition-args condition) :unknown)
1190                (step-condition-args condition)))))
1191   #!+sb-doc
1192   (:documentation "Condition signalled by code compiled with
1193 single-stepping information when about to execute a form.
1194 STEP-CONDITION-FORM holds the form, STEP-CONDITION-PATHNAME holds the
1195 pathname of the original file or NIL, and STEP-CONDITION-SOURCE-PATH
1196 holds the source-path to the original form within that file or NIL.
1197 Associated with this condition are always the restarts STEP-INTO,
1198 STEP-NEXT, and STEP-CONTINUE."))
1199
1200 (define-condition step-result-condition (step-condition)
1201   ((result :initarg :result :reader step-condition-result)))
1202
1203 #!+sb-doc
1204 (setf (fdocumentation 'step-condition-result 'function)
1205       "Return values associated with STEP-VALUES-CONDITION as a list,
1206 or the variable value associated with STEP-VARIABLE-CONDITION.")
1207
1208 (define-condition step-values-condition (step-result-condition)
1209   ()
1210   #!+sb-doc
1211   (:documentation "Condition signalled by code compiled with
1212 single-stepping information after executing a form.
1213 STEP-CONDITION-FORM holds the form, and STEP-CONDITION-RESULT holds
1214 the values returned by the form as a list. No associated restarts."))
1215
1216 (define-condition step-finished-condition (step-condition)
1217   ()
1218   (:report
1219    (lambda (condition stream)
1220      (declare (ignore condition))
1221      (format stream "Returning from STEP")))
1222   #!+sb-doc
1223   (:documentation "Condition signaled when STEP returns."))
1224 \f
1225 ;;; A knob for muffling warnings, mostly for use while loading files.
1226 (defvar *muffled-warnings* 'uninteresting-redefinition
1227   #!+sb-doc
1228   "A type that ought to specify a subtype of WARNING.  Whenever a
1229 warning is signaled, if the warning if of this type and is not
1230 handled by any other handler, it will be muffled.")
1231 \f
1232 ;;; Various STYLE-WARNING signaled in the system.
1233 ;; For the moment, we're only getting into the details for function
1234 ;; redefinitions, but other redefinitions could be done later
1235 ;; (e.g. methods).
1236 (define-condition redefinition-warning (style-warning)
1237   ((name
1238     :initarg :name
1239     :reader redefinition-warning-name)
1240    (new-location
1241     :initarg :new-location
1242     :reader redefinition-warning-new-location)))
1243
1244 (define-condition function-redefinition-warning (redefinition-warning)
1245   ((new-function
1246     :initarg :new-function
1247     :reader function-redefinition-warning-new-function)))
1248
1249 (define-condition redefinition-with-defun (function-redefinition-warning)
1250   ()
1251   (:report (lambda (warning stream)
1252              (format stream "redefining ~/sb-impl::print-symbol-with-prefix/ ~
1253                              in DEFUN"
1254                      (redefinition-warning-name warning)))))
1255
1256 (define-condition redefinition-with-defmacro (function-redefinition-warning)
1257   ()
1258   (:report (lambda (warning stream)
1259              (format stream "redefining ~/sb-impl::print-symbol-with-prefix/ ~
1260                              in DEFMACRO"
1261                      (redefinition-warning-name warning)))))
1262
1263 (define-condition redefinition-with-defgeneric (redefinition-warning)
1264   ()
1265   (:report (lambda (warning stream)
1266              (format stream "redefining ~/sb-impl::print-symbol-with-prefix/ ~
1267                              in DEFGENERIC"
1268                      (redefinition-warning-name warning)))))
1269
1270 (define-condition redefinition-with-defmethod (redefinition-warning)
1271   ((qualifiers :initarg :qualifiers
1272                :reader redefinition-with-defmethod-qualifiers)
1273    (specializers :initarg :specializers
1274                  :reader redefinition-with-defmethod-specializers)
1275    (new-location :initarg :new-location
1276                  :reader redefinition-with-defmethod-new-location)
1277    (old-method :initarg :old-method
1278                :reader redefinition-with-defmethod-old-method))
1279   (:report (lambda (warning stream)
1280              (format stream "redefining ~S~{ ~S~} ~S in DEFMETHOD"
1281                      (redefinition-warning-name warning)
1282                      (redefinition-with-defmethod-qualifiers warning)
1283                      (redefinition-with-defmethod-specializers warning)))))
1284
1285 ;;;; Deciding which redefinitions are "interesting".
1286
1287 (defun function-file-namestring (function)
1288   #!+sb-eval
1289   (when (typep function 'sb!eval:interpreted-function)
1290     (return-from function-file-namestring
1291       (sb!c:definition-source-location-namestring
1292           (sb!eval:interpreted-function-source-location function))))
1293   #!+sb-fasteval
1294   (when (typep function 'sb!interpreter:interpreted-function)
1295     (return-from function-file-namestring
1296       (awhen (sb!interpreter:fun-source-location function)
1297         (sb!c:definition-source-location-namestring it))))
1298   (let* ((fun (%fun-fun function))
1299          (code (fun-code-header fun))
1300          (debug-info (%code-debug-info code))
1301          (debug-source (when debug-info
1302                          (sb!c::debug-info-source debug-info)))
1303          (namestring (when debug-source
1304                        (sb!c::debug-source-namestring debug-source))))
1305     namestring))
1306
1307 (defun interesting-function-redefinition-warning-p (warning old)
1308   (let ((new (function-redefinition-warning-new-function warning))
1309         (source-location (redefinition-warning-new-location warning)))
1310     (or
1311      ;; compiled->interpreted is interesting.
1312      (and (typep old 'compiled-function)
1313           (typep new '(not compiled-function)))
1314      ;; fin->regular is interesting except for interpreted->compiled.
1315      (and (typep new '(not funcallable-instance))
1316           (typep old '(and funcallable-instance
1317                            #!+sb-fasteval (not sb!interpreter:interpreted-function)
1318                            #!+sb-eval (not sb!eval:interpreted-function))))
1319      ;; different file or unknown location is interesting.
1320      (let* ((old-namestring (function-file-namestring old))
1321             (new-namestring
1322              (or (function-file-namestring new)
1323                  (when source-location
1324                    (sb!c::definition-source-location-namestring source-location)))))
1325        (and (or (not old-namestring)
1326                 (not new-namestring)
1327                 (not (string= old-namestring new-namestring))))))))
1328
1329 (setf (info :function :predicate-truth-constraint
1330             'uninteresting-ordinary-function-redefinition-p) 'warning)
1331 (defun uninteresting-ordinary-function-redefinition-p (warning)
1332   (and
1333    (typep warning 'redefinition-with-defun)
1334    ;; Shared logic.
1335    (let ((name (redefinition-warning-name warning)))
1336      (not (interesting-function-redefinition-warning-p
1337            warning (or (fdefinition name) (macro-function name)))))))
1338
1339 (setf (info :function :predicate-truth-constraint
1340             'uninteresting-macro-redefinition-p) 'warning)
1341 (defun uninteresting-macro-redefinition-p (warning)
1342   (and
1343    (typep warning 'redefinition-with-defmacro)
1344    ;; Shared logic.
1345    (let ((name (redefinition-warning-name warning)))
1346      (not (interesting-function-redefinition-warning-p
1347            warning (or (macro-function name) (fdefinition name)))))))
1348
1349 (setf (info :function :predicate-truth-constraint
1350             'uninteresting-generic-function-redefinition-p) 'warning)
1351 (defun uninteresting-generic-function-redefinition-p (warning)
1352   (and
1353    (typep warning 'redefinition-with-defgeneric)
1354    ;; Can't use the shared logic above, since GF's don't get a "new"
1355    ;; definition -- rather the FIN-FUNCTION is set.
1356    (let* ((name (redefinition-warning-name warning))
1357           (old (fdefinition name))
1358           (old-location (when (typep old 'generic-function)
1359                           (sb!pcl::definition-source old)))
1360           (old-namestring (when old-location
1361                             (sb!c:definition-source-location-namestring old-location)))
1362           (new-location (redefinition-warning-new-location warning))
1363           (new-namestring (when new-location
1364                            (sb!c:definition-source-location-namestring new-location))))
1365      (and old-namestring
1366           new-namestring
1367           (string= old-namestring new-namestring)))))
1368
1369 (setf (info :function :predicate-truth-constraint
1370             'uninteresting-method-redefinition-p) 'warning)
1371 (defun uninteresting-method-redefinition-p (warning)
1372   (and
1373    (typep warning 'redefinition-with-defmethod)
1374    ;; Can't use the shared logic above, since GF's don't get a "new"
1375    ;; definition -- rather the FIN-FUNCTION is set.
1376    (let* ((old-method (redefinition-with-defmethod-old-method warning))
1377           (old-location (sb!pcl::definition-source old-method))
1378           (old-namestring (when old-location
1379                             (sb!c:definition-source-location-namestring old-location)))
1380           (new-location (redefinition-warning-new-location warning))
1381           (new-namestring (when new-location
1382                             (sb!c:definition-source-location-namestring new-location))))
1383          (and new-namestring
1384               old-namestring
1385               (string= new-namestring old-namestring)))))
1386
1387 (deftype uninteresting-redefinition ()
1388   '(or (satisfies uninteresting-ordinary-function-redefinition-p)
1389        (satisfies uninteresting-macro-redefinition-p)
1390        (satisfies uninteresting-generic-function-redefinition-p)
1391        (satisfies uninteresting-method-redefinition-p)))
1392
1393 (define-condition redefinition-with-deftransform (redefinition-warning)
1394   ((transform :initarg :transform
1395               :reader redefinition-with-deftransform-transform))
1396   (:report (lambda (warning stream)
1397              (format stream "Overwriting ~S"
1398                      (redefinition-with-deftransform-transform warning)))))
1399 \f
1400 ;;; Various other STYLE-WARNINGS
1401 (define-condition dubious-asterisks-around-variable-name
1402     (style-warning simple-condition)
1403   ()
1404   (:report (lambda (warning stream)
1405              (format stream "~@?, even though the name follows~@
1406 the usual naming convention (names like *FOO*) for special variables"
1407                      (simple-condition-format-control warning)
1408                      (simple-condition-format-arguments warning)))))
1409
1410 (define-condition asterisks-around-lexical-variable-name
1411     (dubious-asterisks-around-variable-name)
1412   ())
1413
1414 (define-condition asterisks-around-constant-variable-name
1415     (dubious-asterisks-around-variable-name)
1416   ())
1417
1418 ;; We call this UNDEFINED-ALIEN-STYLE-WARNING because there are some
1419 ;; subclasses of ERROR above having to do with undefined aliens.
1420 (define-condition undefined-alien-style-warning (style-warning)
1421   ((symbol :initarg :symbol :reader undefined-alien-symbol))
1422   (:report (lambda (warning stream)
1423              (format stream "Undefined alien: ~S"
1424                      (undefined-alien-symbol warning)))))
1425
1426 #!+(or sb-eval sb-fasteval)
1427 (define-condition lexical-environment-too-complex (style-warning)
1428   ((form :initarg :form :reader lexical-environment-too-complex-form)
1429    (lexenv :initarg :lexenv :reader lexical-environment-too-complex-lexenv))
1430   (:report (lambda (warning stream)
1431              (format stream
1432                      "~@<Native lexical environment too complex for ~
1433                          SB-EVAL to evaluate ~S, falling back to ~
1434                          SIMPLE-EVAL-IN-LEXENV.  Lexenv: ~S~:@>"
1435                      (lexical-environment-too-complex-form warning)
1436                      (lexical-environment-too-complex-lexenv warning)))))
1437
1438 ;; If the interpreter is in use (and the REPL is interpreted),
1439 ;; it's easy to accidentally make the macroexpand-hook an interpreted
1440 ;; function. So MACROEXPAND-1 is a little more careful,
1441 ;; and might signal this, instead of only EVAL being able to signal it.
1442 (define-condition macroexpand-hook-type-error (type-error)
1443   ()
1444   (:report (lambda (condition stream)
1445              (format stream "The value of *MACROEXPAND-HOOK* is not a designator for a compiled function: ~S"
1446                      (type-error-datum condition)))))
1447
1448 ;; Although this has -ERROR- in the name, it's just a STYLE-WARNING.
1449 (define-condition character-decoding-error-in-comment (style-warning)
1450   ((stream :initarg :stream :reader decoding-error-in-comment-stream)
1451    (position :initarg :position :reader decoding-error-in-comment-position))
1452   (:report (lambda (warning stream)
1453              (format stream
1454                       "Character decoding error in a ~A-comment at ~
1455                       position ~A reading source stream ~A, ~
1456                       resyncing."
1457                       (decoding-error-in-comment-macro warning)
1458                       (decoding-error-in-comment-position warning)
1459                       (decoding-error-in-comment-stream warning)))))
1460
1461 (define-condition character-decoding-error-in-macro-char-comment
1462     (character-decoding-error-in-comment)
1463   ((char :initform #\; :initarg :char
1464          :reader character-decoding-error-in-macro-char-comment-char)))
1465
1466 (define-condition character-decoding-error-in-dispatch-macro-char-comment
1467     (character-decoding-error-in-comment)
1468   ;; ANSI doesn't give a way for a reader function invoked by a
1469   ;; dispatch macro character to determine which dispatch character
1470   ;; was used, so if a user wants to signal one of these from a custom
1471   ;; comment reader, he'll have to supply the :DISP-CHAR himself.
1472   ((disp-char :initform #\# :initarg :disp-char
1473               :reader character-decoding-error-in-macro-char-comment-disp-char)
1474    (sub-char :initarg :sub-char
1475              :reader character-decoding-error-in-macro-char-comment-sub-char)))
1476
1477 (defun decoding-error-in-comment-macro (warning)
1478   (etypecase warning
1479     (character-decoding-error-in-macro-char-comment
1480      (character-decoding-error-in-macro-char-comment-char warning))
1481     (character-decoding-error-in-dispatch-macro-char-comment
1482      (format
1483       nil "~C~C"
1484       (character-decoding-error-in-macro-char-comment-disp-char warning)
1485       (character-decoding-error-in-macro-char-comment-sub-char warning)))))
1486
1487 (define-condition deprecated-eval-when-situations (style-warning)
1488   ((situations :initarg :situations
1489                :reader deprecated-eval-when-situations-situations))
1490   (:report (lambda (warning stream)
1491              (format stream "using deprecated EVAL-WHEN situation names~{ ~S~}"
1492                      (deprecated-eval-when-situations-situations warning)))))
1493
1494 (define-condition proclamation-mismatch (condition)
1495   ((kind :initarg :kind :reader proclamation-mismatch-kind)
1496    (description :initarg :description :reader proclamation-mismatch-description :initform nil)
1497    (name :initarg :name :reader proclamation-mismatch-name)
1498    (old :initarg :old :reader proclamation-mismatch-old)
1499    (new :initarg :new :reader proclamation-mismatch-new))
1500   (:report
1501    (lambda (condition stream)
1502      ;; if we later decide we want package-qualified names, bind
1503      ;; *PACKAGE* to (find-package "KEYWORD") here.
1504      (format stream
1505              "~@<The new ~A proclamation for~@[ ~A~] ~S~
1506               ~@:_~2@T~S~@:_~
1507               does not match the old ~4:*~A~3* proclamation~
1508               ~@:_~2@T~S~@:>"
1509              (proclamation-mismatch-kind condition)
1510              (proclamation-mismatch-description condition)
1511              (proclamation-mismatch-name condition)
1512              (proclamation-mismatch-new condition)
1513              (proclamation-mismatch-old condition)))))
1514
1515 (define-condition type-proclamation-mismatch (proclamation-mismatch)
1516   ()
1517   (:default-initargs :kind 'type))
1518
1519 (define-condition type-proclamation-mismatch-warning (style-warning
1520                                                       type-proclamation-mismatch)
1521   ())
1522
1523 (define-condition ftype-proclamation-mismatch (proclamation-mismatch)
1524   ()
1525   (:default-initargs :kind 'ftype))
1526
1527 (define-condition ftype-proclamation-mismatch-warning (style-warning
1528                                                        ftype-proclamation-mismatch)
1529   ())
1530
1531 (define-condition ftype-proclamation-mismatch-error (error
1532                                                      ftype-proclamation-mismatch)
1533   ()
1534   (:default-initargs :kind 'ftype :description "known function"))
1535
1536 \f
1537 ;;;; deprecation conditions
1538
1539 (define-condition deprecation-condition (reference-condition)
1540   ((namespace     :initarg :namespace
1541                   :reader deprecation-condition-namespace)
1542    (name          :initarg :name
1543                   :reader deprecation-condition-name)
1544    (replacements  :initarg :replacements
1545                   :reader deprecation-condition-replacements)
1546    (software      :initarg :software
1547                   :reader deprecation-condition-software)
1548    (version       :initarg :version
1549                   :reader deprecation-condition-version)
1550    (runtime-error :initarg :runtime-error
1551                   :reader deprecation-condition-runtime-error
1552                   :initform nil))
1553   (:default-initargs
1554    :namespace (missing-arg)
1555    :name (missing-arg)
1556    :replacements (missing-arg)
1557    :software (missing-arg)
1558    :version (missing-arg)
1559    :references '((:sbcl :node "Deprecation Conditions")))
1560   #!+sb-doc
1561   (:documentation
1562    "Superclass for deprecation-related error and warning
1563 conditions."))
1564
1565 (defmethod print-object ((condition deprecation-condition) stream)
1566   (flet ((print-it (stream)
1567            (print-deprecation-message
1568             (deprecation-condition-namespace condition)
1569             (deprecation-condition-name condition)
1570             (deprecation-condition-software condition)
1571             (deprecation-condition-version condition)
1572             (deprecation-condition-replacements condition)
1573             stream)))
1574     (if *print-escape*
1575         (print-unreadable-object (condition stream :type t)
1576           (print-it stream))
1577         (print-it stream))))
1578
1579 (macrolet ((define-deprecation-warning
1580                (name superclass check-runtime-error format-string
1581                 &optional documentation)
1582              `(progn
1583                 (define-condition ,name (,superclass deprecation-condition)
1584                   ()
1585                   ,@(when documentation
1586                       `((:documentation ,documentation))))
1587
1588                 (def*method print-object :after ((condition ,name) stream)
1589                   (when (and (not *print-escape*)
1590                              ,@(when check-runtime-error
1591                                 `((deprecation-condition-runtime-error condition))))
1592                     (format stream ,format-string
1593                             (deprecation-condition-software condition)
1594                             (deprecation-condition-name condition)))))))
1595
1596   (define-deprecation-warning early-deprecation-warning style-warning nil
1597     (!uncross-format-control
1598      "~%~@<~:@_In future ~A versions ~
1599       ~/sb!impl:print-symbol-with-prefix/ will signal a full warning ~
1600       at compile-time.~:@>")
1601     #!+sb-doc
1602     "This warning is signaled when the use of a variable,
1603 function, type, etc. in :EARLY deprecation is detected at
1604 compile-time. The use will work at run-time with no warning or
1605 error.")
1606
1607   (define-deprecation-warning late-deprecation-warning warning t
1608     (!uncross-format-control
1609      "~%~@<~:@_In future ~A versions ~
1610       ~/sb!impl:print-symbol-with-prefix/ will signal a runtime ~
1611       error.~:@>")
1612     #!+sb-doc
1613     "This warning is signaled when the use of a variable,
1614 function, type, etc. in :LATE deprecation is detected at
1615 compile-time. The use will work at run-time with no warning or
1616 error.")
1617
1618   (define-deprecation-warning final-deprecation-warning warning t
1619     (!uncross-format-control
1620      "~%~@<~:@_~*An error will be signaled at runtime for ~
1621       ~/sb!impl:print-symbol-with-prefix/.~:@>")
1622     #!+sb-doc
1623     "This warning is signaled when the use of a variable,
1624 function, type, etc. in :FINAL deprecation is detected at
1625 compile-time. An error will be signaled at run-time."))
1626
1627 (define-condition deprecation-error (error deprecation-condition)
1628   ()
1629   #!+sb-doc
1630   (:documentation
1631    "This error is signaled at run-time when an attempt is made to use
1632 a thing that is in :FINAL deprecation, i.e. call a function or access
1633 a variable."))
1634 \f
1635 ;;;; restart definitions
1636
1637 (define-condition abort-failure (control-error) ()
1638   (:report
1639    "An ABORT restart was found that failed to transfer control dynamically."))
1640
1641 (defun abort (&optional condition)
1642   #!+sb-doc
1643   "Transfer control to a restart named ABORT, signalling a CONTROL-ERROR if
1644    none exists."
1645   (invoke-restart (find-restart-or-control-error 'abort condition))
1646   ;; ABORT signals an error in case there was a restart named ABORT
1647   ;; that did not transfer control dynamically. This could happen with
1648   ;; RESTART-BIND.
1649   (error 'abort-failure))
1650
1651 (defun muffle-warning (&optional condition)
1652   #!+sb-doc
1653   "Transfer control to a restart named MUFFLE-WARNING, signalling a
1654    CONTROL-ERROR if none exists."
1655   (invoke-restart (find-restart-or-control-error 'muffle-warning condition)))
1656
1657 (defun try-restart (name condition &rest arguments)
1658   (let ((restart (find-restart name condition)))
1659     (when restart
1660       (apply #'invoke-restart restart arguments))))
1661
1662 (macrolet ((define-nil-returning-restart (name args doc)
1663              #!-sb-doc (declare (ignore doc))
1664              `(defun ,name (,@args &optional condition)
1665                 #!+sb-doc ,doc
1666                 (try-restart ',name condition ,@args))))
1667   (define-nil-returning-restart continue ()
1668     "Transfer control to a restart named CONTINUE, or return NIL if none exists.")
1669   (define-nil-returning-restart store-value (value)
1670     "Transfer control and VALUE to a restart named STORE-VALUE, or
1671 return NIL if none exists.")
1672   (define-nil-returning-restart use-value (value)
1673     "Transfer control and VALUE to a restart named USE-VALUE, or
1674 return NIL if none exists.")
1675   (define-nil-returning-restart print-unreadably ()
1676     "Transfer control to a restart named SB-EXT:PRINT-UNREADABLY, or
1677 return NIL if none exists."))
1678
1679 ;;; single-stepping restarts
1680
1681 (macrolet ((def (name doc)
1682                #!-sb-doc (declare (ignore doc))
1683                `(defun ,name (condition)
1684                  #!+sb-doc ,doc
1685                  (invoke-restart (find-restart-or-control-error ',name condition)))))
1686   (def step-continue
1687       "Transfers control to the STEP-CONTINUE restart associated with
1688 the condition, continuing execution without stepping. Signals a
1689 CONTROL-ERROR if the restart does not exist.")
1690   (def step-next
1691       "Transfers control to the STEP-NEXT restart associated with the
1692 condition, executing the current form without stepping and continuing
1693 stepping with the next form. Signals CONTROL-ERROR is the restart does
1694 not exists.")
1695   (def step-into
1696       "Transfers control to the STEP-INTO restart associated with the
1697 condition, stepping into the current form. Signals a CONTROL-ERROR is
1698 the restart does not exist."))
1699
1700 ;;; Compiler macro magic
1701
1702 (define-condition compiler-macro-keyword-problem ()
1703   ((argument :initarg :argument :reader compiler-macro-keyword-argument))
1704   (:report (lambda (condition stream)
1705              (format stream "~@<Argument ~S in keyword position is not ~
1706                              a self-evaluating symbol, preventing compiler-macro ~
1707                              expansion.~@:>"
1708                      (compiler-macro-keyword-argument condition)))))
1709
1710 ;; After (or if) we deem this the optimal name for this condition,
1711 ;; it should be exported from SB-EXT so that people can muffle it.
1712 (define-condition sb!c:inlining-dependency-failure (simple-style-warning) ())
1713
1714 (/show0 "condition.lisp end of file")