  stuff originally from CMU CL 's error.lisp which can or should
;;;; come late (mostly related to the CONDITION class itself)
;;;;

  This software is part of the SBCL system . See the README file for
;;;; more information.
;;;;
  This software is derived from the CMU CL system , which was
  written at Carnegie Mellon University and released into the
;;;; public domain. The software is in the public domain and is
;;;; provided with absolutely no warranty. See the COPYING and CREDITS
;;;; files for more information.

(in-package "SB!KERNEL")

;;;; the CONDITION class

(/show0 "condition.lisp 20")

(eval-when (:compile-toplevel :load-toplevel :execute)

(/show0 "condition.lisp 24")

(def!struct (condition-classoid (:include classoid)
                                (:constructor make-condition-classoid))
  ;; list of CONDITION-SLOT structures for the direct slots of this
  ;; class
  (slots nil :type list)
  ;; list of CONDITION-SLOT structures for all of the effective class
  ;; slots of this class
  (class-slots nil :type list)
  report function or NIL
  (report nil :type (or function null))
  ;; list of alternating initargs and initforms
  (default-initargs () :type list)
  ;; class precedence list as a list of CLASS objects, with all
  ;; non-CONDITION classes removed
  (cpl () :type list)
  ;; a list of all the effective instance allocation slots of this
  class that have a non - constant initform or default - initarg .
  ;; Values for these slots must be computed in the dynamic
  ;; environment of MAKE-CONDITION.
  (hairy-slots nil :type list))

(/show0 "condition.lisp 49")

  EVAL - WHEN

(!defstruct-with-alternate-metaclass condition
  :slot-names (actual-initargs assigned-slots)
  :boa-constructor %make-condition-object
  :superclass-name t
  :metaclass-name condition-classoid
  :metaclass-constructor make-condition-classoid
  :dd-type structure)

(defun make-condition-object (actual-initargs)
  (%make-condition-object actual-initargs nil))

(defstruct (condition-slot (:copier nil))
  (name (missing-arg) :type symbol)
  ;; list of all applicable initargs
  (initargs (missing-arg) :type list)
  ;; names of reader and writer functions
  (readers (missing-arg) :type list)
  (writers (missing-arg) :type list)
  true if : INITFORM was specified
  (initform-p (missing-arg) :type (member t nil))
  ;; If this is a function, call it with no args. Otherwise, it's the
  ;; actual value.
  (initform (missing-arg) :type t)
  allocation of this slot , or NIL until defaulted
  (allocation nil :type (member :instance :class nil))
  ;; If ALLOCATION is :CLASS, this is a cons whose car holds the value.
  (cell nil :type (or cons null))
  ;; slot documentation
  (documentation nil :type (or string null)))

   : It 's not clear to me why CONDITION - CLASS has itself listed
  in its CPL , while other classes derived from CONDITION - CLASS do n't
;;; have themselves listed in their CPLs. This behavior is inherited
  from CMU CL , and did n't seem to be explained there , and I have n't
  figured out whether it 's right . -- WHN 19990612
(eval-when (:compile-toplevel :load-toplevel :execute)
  (/show0 "condition.lisp 103")
  (let ((condition-class (locally
   : There 's a DEFTRANSFORM
                           ;; FIND-CLASSOID for constant class names
                           ;; which creates fast but
                           ;; non-cold-loadable, non-compact code. In
                           ;; this context, we'd rather have compact,
  cold - loadable code . -- WHN 19990928
                           (declare (notinline find-classoid))
                           (find-classoid 'condition))))
    (setf (condition-classoid-cpl condition-class)
          (list condition-class)))
  (/show0 "condition.lisp 103"))

(setf (condition-classoid-report (locally
   : There 's a DEFTRANSFORM
                                   ;; FIND-CLASSOID for constant class
                                   ;; names which creates fast but
                                   ;; non-cold-loadable, non-compact
                                   ;; code. In this context, we'd
                                   ;; rather have compact,
  cold - loadable code . -- WHN
  19990928
                                   (declare (notinline find-classoid))
                                   (find-classoid 'condition)))
      (lambda (cond stream)
        (format stream "Condition ~S was signalled." (type-of cond))))

(eval-when (:compile-toplevel :load-toplevel :execute)

(defun find-condition-layout (name parent-types)
  (let* ((cpl (remove-duplicates
               (reverse
                (reduce #'append
                        (mapcar (lambda (x)
                                  (condition-classoid-cpl
                                   (find-classoid x)))
                                parent-types)))))
         (cond-layout (info :type :compiler-layout 'condition))
         (olayout (info :type :compiler-layout name))
         ;; FIXME: Does this do the right thing in case of multiple
         ;; inheritance? A quick look at DEFINE-CONDITION didn't make
         ;; it obvious what ANSI intends to be done in the case of
         ;; multiple inheritance, so it's not actually clear what the
         ;; right thing is..
         (new-inherits
          (order-layout-inherits (concatenate 'simple-vector
                                              (layout-inherits cond-layout)
                                              (mapcar #'classoid-layout cpl)))))
    (if (and olayout
             (not (mismatch (layout-inherits olayout) new-inherits)))
        olayout
        (make-layout :classoid (make-undefined-classoid name)
                     :inherits new-inherits
                     :depthoid -1
                     :length (layout-length cond-layout)))))

  EVAL - WHEN

  FIXME : ANSI 's definition of DEFINE - CONDITION says
;;;   Condition reporting is mediated through the PRINT-OBJECT method
;;;   for the condition type in question, with *PRINT-ESCAPE* always
;;;   being nil. Specifying (:REPORT REPORT-NAME) in the definition of
;;;   a condition type C is equivalent to:
      ( defmethod print - object ( ( x c ) stream )
;;;       (if *print-escape* (call-next-method) (report-name x stream)))
;;; The current code doesn't seem to quite match that.
(def!method print-object ((x condition) stream)
  (if *print-escape*
      (if (and (typep x 'simple-condition) (slot-value x 'format-control))
          (print-unreadable-object (x stream :type t :identity t)
            (write (simple-condition-format-control x)
                   :stream stream
                   :lines 1))
          (print-unreadable-object (x stream :type t :identity t)))
   : A comment from CMU CL here said
    7/13/98 BUG ? CPL is not sorted and results here depend on order of
      ;;   superclasses in define-condition call!
      (dolist (class (condition-classoid-cpl (classoid-of x))
                     (error "no REPORT? shouldn't happen!"))
        (let ((report (condition-classoid-report class)))
          (when report
            (return (funcall report x stream)))))))

;;;; slots of CONDITION objects

(defvar *empty-condition-slot* '(empty))

(defun find-slot-default (class slot)
  (let ((initargs (condition-slot-initargs slot))
        (cpl (condition-classoid-cpl class)))
    (dolist (class cpl)
      (let ((default-initargs (condition-classoid-default-initargs class)))
        (dolist (initarg initargs)
          (let ((val (getf default-initargs initarg *empty-condition-slot*)))
            (unless (eq val *empty-condition-slot*)
              (return-from find-slot-default
                           (if (functionp val)
                               (funcall val)
                               val)))))))

    (if (condition-slot-initform-p slot)
        (let ((initform (condition-slot-initform slot)))
          (if (functionp initform)
              (funcall initform)
              initform))
        (error "unbound condition slot: ~S" (condition-slot-name slot)))))

(defun find-condition-class-slot (condition-class slot-name)
  (dolist (sclass
           (condition-classoid-cpl condition-class)
           (error "There is no slot named ~S in ~S."
                  slot-name condition-class))
    (dolist (slot (condition-classoid-slots sclass))
      (when (eq (condition-slot-name slot) slot-name)
        (return-from find-condition-class-slot slot)))))

(defun condition-writer-function (condition new-value name)
  (dolist (cslot (condition-classoid-class-slots
                  (layout-classoid (%instance-layout condition)))
                 (setf (getf (condition-assigned-slots condition) name)
                       new-value))
    (when (eq (condition-slot-name cslot) name)
      (return (setf (car (condition-slot-cell cslot)) new-value)))))

(defun condition-reader-function (condition name)
  (let ((class (layout-classoid (%instance-layout condition))))
    (dolist (cslot (condition-classoid-class-slots class))
      (when (eq (condition-slot-name cslot) name)
        (return-from condition-reader-function
                     (car (condition-slot-cell cslot)))))
    (let ((val (getf (condition-assigned-slots condition) name
                     *empty-condition-slot*)))
      (if (eq val *empty-condition-slot*)
          (let ((actual-initargs (condition-actual-initargs condition))
                (slot (find-condition-class-slot class name)))
            (unless slot
              (error "missing slot ~S of ~S" name condition))
            (do ((initargs actual-initargs (cddr initargs)))
                ((endp initargs)
                 (setf (getf (condition-assigned-slots condition) name)
                       (find-slot-default class slot)))
              (when (member (car initargs) (condition-slot-initargs slot))
                (return-from condition-reader-function
                  (setf (getf (condition-assigned-slots condition)
                              name)
                        (cadr initargs))))))
          val))))

;;;; MAKE-CONDITION

(defun make-condition (type &rest args)
  #!+sb-doc
  "Make an instance of a condition object using the specified initargs."
  ;; Note: ANSI specifies no exceptional situations in this function.
  ;; signalling simple-type-error would not be wrong.
  (let* ((type (or (and (symbolp type) (find-classoid type nil))
                    type))
         (class (typecase type
                  (condition-classoid type)
                  (class
  Punt to CLOS .
                   (return-from make-condition
                     (apply #'make-instance type args)))
                  (classoid
                   (error 'simple-type-error
                          :datum type
                          :expected-type 'condition-class
                          :format-control "~S is not a condition class."
                          :format-arguments (list type)))
                  (t
                   (error 'simple-type-error
                          :datum type
                          :expected-type 'condition-class
                          :format-control
                          "~s doesn't designate a condition class."
                          :format-arguments (list type)))))
         (res (make-condition-object args)))
    (setf (%instance-layout res) (classoid-layout class))
    ;; Set any class slots with initargs present in this call.
    (dolist (cslot (condition-classoid-class-slots class))
      (dolist (initarg (condition-slot-initargs cslot))
        (let ((val (getf args initarg *empty-condition-slot*)))
          (unless (eq val *empty-condition-slot*)
            (setf (car (condition-slot-cell cslot)) val)))))
    ;; Default any slots with non-constant defaults now.
    (dolist (hslot (condition-classoid-hairy-slots class))
      (when (dolist (initarg (condition-slot-initargs hslot) t)
              (unless (eq (getf args initarg *empty-condition-slot*)
                          *empty-condition-slot*)
                (return nil)))
        (setf (getf (condition-assigned-slots res) (condition-slot-name hslot))
              (find-slot-default class hslot))))
    res))

;;;; DEFINE-CONDITION

(eval-when (:compile-toplevel :load-toplevel :execute)
(defun %compiler-define-condition (name direct-supers layout
                                   all-readers all-writers)
  (with-single-package-locked-error
      (:symbol name "defining ~A as a condition")
    (sb!xc:proclaim `(ftype (function (t) t) ,@all-readers))
    (sb!xc:proclaim `(ftype (function (t t) t) ,@all-writers))
    (multiple-value-bind (class old-layout)
        (insured-find-classoid name
                               #'condition-classoid-p
                               #'make-condition-classoid)
      (setf (layout-classoid layout) class)
      (setf (classoid-direct-superclasses class)
            (mapcar #'find-classoid direct-supers))
      (cond ((not old-layout)
             (register-layout layout))
            ((not *type-system-initialized*)
             (setf (layout-classoid old-layout) class)
             (setq layout old-layout)
             (unless (eq (classoid-layout class) layout)
               (register-layout layout)))
            ((redefine-layout-warning "current"
                                      old-layout
                                      "new"
                                      (layout-length layout)
                                      (layout-inherits layout)
                                      (layout-depthoid layout)
                                      (layout-n-untagged-slots layout))
             (register-layout layout :invalidate t))
            ((not (classoid-layout class))
             (register-layout layout)))

      (setf (layout-info layout)
            (locally
   : There 's a FIND - CLASS DEFTRANSFORM for constant class
                ;; names which creates fast but non-cold-loadable, non-compact
                ;; code. In this context, we'd rather have compact, cold-loadable
  code . -- WHN 19990928
                (declare (notinline find-classoid))
              (layout-info (classoid-layout (find-classoid 'condition)))))

      (setf (find-classoid name) class)

  Initialize CPL slot .
      (setf (condition-classoid-cpl class)
            (remove-if-not #'condition-classoid-p
                           (std-compute-class-precedence-list class)))))
  (values))
  EVAL - WHEN

;;; Compute the effective slots of CLASS, copying inherited slots and
;;; destructively modifying direct slots.
;;;
;;; FIXME: It'd be nice to explain why it's OK to destructively modify
;;; direct slots. Presumably it follows from the semantics of
;;; inheritance and redefinition of conditions, but finding the cite
;;; and documenting it here would be good. (Or, if this is not in fact
;;; ANSI-compliant, fixing it would also be good.:-)
(defun compute-effective-slots (class)
  (collect ((res (copy-list (condition-classoid-slots class))))
    (dolist (sclass (cdr (condition-classoid-cpl class)))
      (dolist (sslot (condition-classoid-slots sclass))
        (let ((found (find (condition-slot-name sslot) (res)
                           :key #'condition-slot-name)))
          (cond (found
                 (setf (condition-slot-initargs found)
                       (union (condition-slot-initargs found)
                              (condition-slot-initargs sslot)))
                 (unless (condition-slot-initform-p found)
                   (setf (condition-slot-initform-p found)
                         (condition-slot-initform-p sslot))
                   (setf (condition-slot-initform found)
                         (condition-slot-initform sslot)))
                 (unless (condition-slot-allocation found)
                   (setf (condition-slot-allocation found)
                         (condition-slot-allocation sslot))))
                (t
                 (res (copy-structure sslot)))))))
    (res)))

;;; Early definitions of slot accessor creators.
;;;
  Slot accessors must be generic functions , but ANSI does not seem
;;; to specify any of them, and we cannot support it before end of
  warm init . So we use ordinary functions inside SBCL , and switch to
;;; GFs only at the end of building.
(declaim (notinline install-condition-slot-reader
                    install-condition-slot-writer))
(defun install-condition-slot-reader (name condition slot-name)
  (declare (ignore condition))
  (setf (fdefinition name)
        (lambda (condition)
          (condition-reader-function condition slot-name))))
(defun install-condition-slot-writer (name condition slot-name)
  (declare (ignore condition))
  (setf (fdefinition name)
        (lambda (new-value condition)
          (condition-writer-function condition new-value slot-name))))

(defvar *define-condition-hooks* nil)

(defun %set-condition-report (name report)
  (setf (condition-classoid-report (find-classoid name))
        report))

(defun %define-condition (name parent-types layout slots documentation
                          default-initargs all-readers all-writers
                          source-location)
  (with-single-package-locked-error
      (:symbol name "defining ~A as a condition")
    (%compiler-define-condition name parent-types layout all-readers all-writers)
    (sb!c:with-source-location (source-location)
      (setf (layout-source-location layout)
            source-location))
    (let ((class (find-classoid name)))
      (setf (condition-classoid-slots class) slots)
      (setf (condition-classoid-default-initargs class) default-initargs)
      (setf (fdocumentation name 'type) documentation)

      (dolist (slot slots)

        ;; Set up reader and writer functions.
        (let ((slot-name (condition-slot-name slot)))
          (dolist (reader (condition-slot-readers slot))
            (install-condition-slot-reader reader name slot-name))
          (dolist (writer (condition-slot-writers slot))
            (install-condition-slot-writer writer name slot-name))))

      ;; Compute effective slots and set up the class and hairy slots
      ;; (subsets of the effective slots.)
      (let ((eslots (compute-effective-slots class))
            (e-def-initargs
             (reduce #'append
                     (mapcar #'condition-classoid-default-initargs
                           (condition-classoid-cpl class)))))
        (dolist (slot eslots)
          (ecase (condition-slot-allocation slot)
            (:class
             (unless (condition-slot-cell slot)
               (setf (condition-slot-cell slot)
                     (list (if (condition-slot-initform-p slot)
                               (let ((initform (condition-slot-initform slot)))
                                 (if (functionp initform)
                                     (funcall initform)
                                     initform))
                               *empty-condition-slot*))))
             (push slot (condition-classoid-class-slots class)))
            ((:instance nil)
             (setf (condition-slot-allocation slot) :instance)
             (when (or (functionp (condition-slot-initform slot))
                       (dolist (initarg (condition-slot-initargs slot) nil)
                         (when (functionp (getf e-def-initargs initarg))
                           (return t))))
               (push slot (condition-classoid-hairy-slots class)))))))
      (when (boundp '*define-condition-hooks*)
        (dolist (fun *define-condition-hooks*)
          (funcall fun class))))
    name))

(defmacro define-condition (name (&rest parent-types) (&rest slot-specs)
                                 &body options)
  #!+sb-doc
  "DEFINE-CONDITION Name (Parent-Type*) (Slot-Spec*) Option*
   Define NAME as a condition type. This new type inherits slots and its
   report function from the specified PARENT-TYPEs. A slot spec is a list of:
     (slot-name :reader <rname> :initarg <iname> {Option Value}*

   The DEFINE-CLASS slot options :ALLOCATION, :INITFORM, [slot] :DOCUMENTATION
   and :TYPE and the overall options :DEFAULT-INITARGS and
   [type] :DOCUMENTATION are also allowed.

   The :REPORT option is peculiar to DEFINE-CONDITION. Its argument is either
   a string or a two-argument lambda or function name. If a function, the
   function is called with the condition and stream to report the condition.
   If a string, the string is printed.

   Condition types are classes, but (as allowed by ANSI and not as described in
   CLtL2) are neither STANDARD-OBJECTs nor STRUCTURE-OBJECTs. WITH-SLOTS and
   SLOT-VALUE may not be used on condition objects."
  (let* ((parent-types (or parent-types '(condition)))
         (layout (find-condition-layout name parent-types))
         (documentation nil)
         (report nil)
         (default-initargs ()))
    (collect ((slots)
              (all-readers nil append)
              (all-writers nil append))
      (dolist (spec slot-specs)
        (when (keywordp spec)
          (warn "Keyword slot name indicates probable syntax error:~%  ~S"
                spec))
        (let* ((spec (if (consp spec) spec (list spec)))
               (slot-name (first spec))
               (allocation :instance)
               (initform-p nil)
               documentation
               initform)
          (collect ((initargs)
                    (readers)
                    (writers))
            (do ((options (rest spec) (cddr options)))
                ((null options))
              (unless (and (consp options) (consp (cdr options)))
                (error "malformed condition slot spec:~%  ~S." spec))
              (let ((arg (second options)))
                (case (first options)
                  (:reader (readers arg))
                  (:writer (writers arg))
                  (:accessor
                   (readers arg)
                   (writers `(setf ,arg)))
                  (:initform
                   (when initform-p
                     (error "more than one :INITFORM in ~S" spec))
                   (setq initform-p t)
                   (setq initform arg))
                  (:initarg (initargs arg))
                  (:allocation
                   (setq allocation arg))
                  (:documentation
                   (when documentation
                     (error "more than one :DOCUMENTATION in ~S" spec))
                   (unless (stringp arg)
                     (error "slot :DOCUMENTATION argument is not a string: ~S"
                            arg))
                   (setq documentation arg))
                  (:type)
                  (t
                   (error "unknown slot option:~%  ~S" (first options))))))

            (all-readers (readers))
            (all-writers (writers))
            (slots `(make-condition-slot
                     :name ',slot-name
                     :initargs ',(initargs)
                     :readers ',(readers)
                     :writers ',(writers)
                     :initform-p ',initform-p
                     :documentation ',documentation
                     :initform
                     ,(if (sb!xc:constantp initform)
                          `',(constant-form-value initform)
                          `#'(lambda () ,initform)))))))

      (dolist (option options)
        (unless (consp option)
          (error "bad option:~%  ~S" option))
        (case (first option)
          (:documentation (setq documentation (second option)))
          (:report
           (let ((arg (second option)))
             (setq report
                   (if (stringp arg)
                       `#'(lambda (condition stream)
                            (declare (ignore condition))
                            (write-string ,arg stream))
                       `#'(lambda (condition stream)
                            (funcall #',arg condition stream))))))
          (:default-initargs
           (do ((initargs (rest option) (cddr initargs)))
               ((endp initargs))
             (let ((val (second initargs)))
               (setq default-initargs
                     (list* `',(first initargs)
                            (if (sb!xc:constantp val)
                                `',(constant-form-value val)
                                `#'(lambda () ,val))
                            default-initargs)))))
          (t
           (error "unknown option: ~S" (first option)))))

      `(progn
         (eval-when (:compile-toplevel)
           (%compiler-define-condition ',name ',parent-types ',layout
                                       ',(all-readers) ',(all-writers)))
         (eval-when (:load-toplevel :execute)
           (%define-condition ',name
                              ',parent-types
                              ',layout
                              (list ,@(slots))
                              ,documentation
                              (list ,@default-initargs)
                              ',(all-readers)
                              ',(all-writers)
                              (sb!c:source-location))
           ;; This needs to be after %DEFINE-CONDITION in case :REPORT
           ;; is a lambda referring to condition slot accessors:
           ;; they're not proclaimed as functions before it has run if
  we 're under EVAL or loaded as source .
           (%set-condition-report ',name ,report)
           ',name)))))

  various CONDITIONs specified by ANSI

(define-condition serious-condition (condition) ())

(define-condition error (serious-condition) ())

(define-condition warning (condition) ())
(define-condition style-warning (warning) ())

(defun simple-condition-printer (condition stream)
  (let ((control (simple-condition-format-control condition)))
    (if control
        (apply #'format stream
               control
               (simple-condition-format-arguments condition))
        (error "No format-control for ~S" condition))))

(define-condition simple-condition ()
  ((format-control :reader simple-condition-format-control
                   :initarg :format-control
                   :initform nil
                   :type format-control)
   (format-arguments :reader simple-condition-format-arguments
                     :initarg :format-arguments
                     :initform nil
                     :type list))
  (:report simple-condition-printer))

(define-condition simple-warning (simple-condition warning) ())

(define-condition simple-error (simple-condition error) ())

(define-condition storage-condition (serious-condition) ())

(define-condition type-error (error)
  ((datum :reader type-error-datum :initarg :datum)
   (expected-type :reader type-error-expected-type :initarg :expected-type))
  (:report
   (lambda (condition stream)
     (format stream
             "~@<The value ~2I~:_~S ~I~_is not of type ~2I~_~S.~:>"
             (type-error-datum condition)
             (type-error-expected-type condition)))))

(def!method print-object ((condition type-error) stream)
  (if *print-escape*
      (flet ((maybe-string (thing)
               (ignore-errors
                 (write-to-string thing :lines 1 :readably nil :array nil :pretty t))))
        (let ((type (maybe-string (type-error-expected-type condition)))
              (datum (maybe-string (type-error-datum condition))))
          (if (and type datum)
              (print-unreadable-object (condition stream :type t)
                (format stream "~@<expected-type: ~A ~_datum: ~A~:@>" type datum))
              (call-next-method))))
      (call-next-method)))

  not specified by ANSI , but too useful not to have around .
(define-condition simple-style-warning (simple-condition style-warning) ())
(define-condition simple-type-error (simple-condition type-error) ())

;; Can't have a function called SIMPLE-TYPE-ERROR or TYPE-ERROR...
(declaim (ftype (sfunction (t t t &rest t) nil) bad-type))
(defun bad-type (datum type control &rest arguments)
  (error 'simple-type-error
         :datum datum
         :expected-type type
         :format-control control
         :format-arguments arguments))

(define-condition program-error (error) ())
(define-condition parse-error   (error) ())
(define-condition control-error (error) ())
(define-condition stream-error  (error)
  ((stream :reader stream-error-stream :initarg :stream)))

(define-condition end-of-file (stream-error) ()
  (:report
   (lambda (condition stream)
     (format stream
             "end of file on ~S"
             (stream-error-stream condition)))))

(define-condition closed-stream-error (stream-error) ()
  (:report
   (lambda (condition stream)
     (format stream "~S is closed" (stream-error-stream condition)))))

(define-condition file-error (error)
  ((pathname :reader file-error-pathname :initarg :pathname))
  (:report
   (lambda (condition stream)
     (format stream "error on file ~S" (file-error-pathname condition)))))

(define-condition package-error (error)
  ((package :reader package-error-package :initarg :package)))

(define-condition cell-error (error)
  ((name :reader cell-error-name :initarg :name)))

(def!method print-object ((condition cell-error) stream)
  (if (and *print-escape* (slot-boundp condition 'name))
      (print-unreadable-object (condition stream :type t :identity t)
        (princ (cell-error-name condition) stream))
      (call-next-method)))

(define-condition unbound-variable (cell-error) ()
  (:report
   (lambda (condition stream)
     (format stream
             "The variable ~S is unbound."
             (cell-error-name condition)))))

(define-condition undefined-function (cell-error) ()
  (:report
   (lambda (condition stream)
     (format stream
             "The function ~/sb-impl::print-symbol-with-prefix/ is undefined."
             (cell-error-name condition)))))

(define-condition special-form-function (undefined-function) ()
  (:report
   (lambda (condition stream)
     (format stream
             "Cannot FUNCALL the SYMBOL-FUNCTION of special operator ~S."
             (cell-error-name condition)))))

(define-condition arithmetic-error (error)
  ((operation :reader arithmetic-error-operation
              :initarg :operation
              :initform nil)
   (operands :reader arithmetic-error-operands
             :initarg :operands))
  (:report (lambda (condition stream)
             (format stream
                     "arithmetic error ~S signalled"
                     (type-of condition))
             (when (arithmetic-error-operation condition)
               (format stream
                       "~%Operation was ~S, operands ~S."
                       (arithmetic-error-operation condition)
                       (arithmetic-error-operands condition))))))

(define-condition division-by-zero         (arithmetic-error) ())
(define-condition floating-point-overflow  (arithmetic-error) ())
(define-condition floating-point-underflow (arithmetic-error) ())
(define-condition floating-point-inexact   (arithmetic-error) ())
(define-condition floating-point-invalid-operation (arithmetic-error) ())

(define-condition print-not-readable (error)
  ((object :reader print-not-readable-object :initarg :object))
  (:report
   (lambda (condition stream)
     (let ((obj (print-not-readable-object condition))
           (*print-array* nil))
       (format stream "~S cannot be printed readably." obj)))))

(define-condition reader-error (parse-error stream-error) ()
  (:report (lambda (condition stream)
             (%report-reader-error condition stream))))

;;; a READER-ERROR whose REPORTing is controlled by FORMAT-CONTROL and
  FORMAT - ARGS ( the usual case for READER - ERRORs signalled from
  within SBCL itself )
;;;
;;; (Inheriting CL:SIMPLE-CONDITION here isn't quite consistent with
  the letter of the ANSI spec : this is not a condition signalled by
  SIGNAL when a format - control is supplied by the function 's first
  argument . It seems to me ( WHN ) to be basically in the spirit of
;;; the spec, but if not, it'd be straightforward to do our own
;;; DEFINE-CONDITION SB-INT:SIMPLISTIC-CONDITION with
;;; FORMAT-CONTROL and FORMAT-ARGS slots, and use that condition in
  place of CL : SIMPLE - CONDITION here . )
(define-condition simple-reader-error (reader-error simple-condition)
  ()
  (:report (lambda (condition stream)
             (%report-reader-error condition stream :simple t))))

;;; base REPORTing of a READER-ERROR
;;;
;;; When SIMPLE, we expect and use SIMPLE-CONDITION-ish FORMAT-CONTROL
;;; and FORMAT-ARGS slots.
(defun %report-reader-error (condition stream &key simple position)
  (let ((error-stream (stream-error-stream condition)))
    (pprint-logical-block (stream nil)
      (if simple
          (apply #'format stream
                 (simple-condition-format-control condition)
                 (simple-condition-format-arguments condition))
          (prin1 (class-name (class-of condition)) stream))
      (format stream "~2I~@[~_~_~:{~:(~A~): ~S~:^, ~:_~}~]~_~_Stream: ~S"
              (stream-error-position-info error-stream position)
              error-stream))))

  special SBCL extension conditions

  an error apparently caused by a bug in SBCL itself
;;;
;;; Note that we don't make any serious effort to use this condition
  for * all * errors in SBCL itself . E.g. type errors and array
  indexing errors can occur in functions called from SBCL code , and
;;; will just end up as ordinary TYPE-ERROR or invalid index error,
;;; because the signalling code has no good way to know that the
  underlying problem is a bug in SBCL . But in the fairly common case
  that the signalling code does know that it 's found a bug in SBCL ,
;;; this condition is appropriate, reusing boilerplate and helping
  users to recognize it as an SBCL bug .
(define-condition bug (simple-error)
  ()
  (:report
   (lambda (condition stream)
     (format stream
             "~@<  ~? ~:@_~?~:>"
             (simple-condition-format-control condition)
             (simple-condition-format-arguments condition)
             "~@<This is probably a bug in SBCL itself. (Alternatively, ~
              SBCL might have been corrupted by bad user code, e.g. by an ~
              undefined Lisp operation like ~S, or by stray pointers from ~
              alien code or from unsafe Lisp code; or there might be a bug ~
              in the OS or hardware that SBCL is running on.) If it seems to ~
              be a bug in SBCL itself, the maintainers would like to know ~
              about it. Bug reports are welcome on the SBCL ~
              mailing lists, which you can find at ~
              </>.~:@>"
             '((fmakunbound 'compile))))))

(define-condition simple-storage-condition (storage-condition simple-condition)
  ())

;;; a condition for use in stubs for operations which aren't supported
;;; on some platforms
;;;
  E.g. in  , it might be appropriate to do something like
    # -(or   )
;;;   (defun load-foreign (&rest rest)
;;;     (error 'unsupported-operator :name 'load-foreign))
    # + ( or   )
;;;   (defun load-foreign ... actual definition ...)
;;; By signalling a standard condition in this case, we make it
  possible for test code to distinguish between ( 1 ) intentionally
  unimplemented and ( 2 ) unintentionally just screwed up somehow .
;;; (Before this condition was defined, test code tried to deal with
;;; this by checking for FBOUNDP, but that didn't work reliably. In
  sbcl-0.7.0 , a package screwup left the definition of
;;; LOAD-FOREIGN in the wrong package, so it was unFBOUNDP even on
;;; architectures where it was supposed to be supported, and the
;;; regression tests cheerfully passed because they assumed that
;;; unFBOUNDPness meant they were running on an system which didn't
;;; support the extension.)
(define-condition unsupported-operator (simple-error) ())

;;; (:ansi-cl :function remove)
;;; (:ansi-cl :section (a b c))
;;; (:ansi-cl :glossary "similar")
;;;
  (:  : node " ... " )
  (:  : variable * ed - functions * )
;;;
;;; FIXME: this is not the right place for this.
(defun print-reference (reference stream)
  (ecase (car reference)
    (:amop
     (format stream "AMOP")
     (format stream ", ")
     (destructuring-bind (type data) (cdr reference)
       (ecase type
         (:readers "Readers for ~:(~A~) Metaobjects"
                   (substitute #\  #\- (symbol-name data)))
         (:initialization
          (format stream "Initialization of ~:(~A~) Metaobjects"
                  (substitute #\  #\- (symbol-name data))))
         (:generic-function (format stream "Generic Function ~S" data))
         (:function (format stream "Function ~S" data))
         (:section (format stream "Section ~{~D~^.~}" data)))))
    (:ansi-cl
     (format stream "The ANSI Standard")
     (format stream ", ")
     (destructuring-bind (type data) (cdr reference)
       (ecase type
         (:function (format stream "Function ~S" data))
         (:special-operator (format stream "Special Operator ~S" data))
         (:macro (format stream "Macro ~S" data))
         (:section (format stream "Section ~{~D~^.~}" data))
         (:glossary (format stream "Glossary entry for ~S" data))
         (:issue (format stream "writeup for Issue ~A" data)))))
    (:sbcl
     (format stream "The SBCL Manual")
     (format stream ", ")
     (destructuring-bind (type data) (cdr reference)
       (ecase type
         (:node (format stream "Node ~S" data))
         (:variable (format stream "Variable ~S" data))
         (:function (format stream "Function ~S" data)))))
  FIXME : other documents ( e.g. CLIM , Franz documentation :-)
    ))
(define-condition reference-condition ()
  ((references :initarg :references :reader reference-condition-references)))
(defvar *print-condition-references* t)
(def!method print-object :around ((o reference-condition) s)
  (call-next-method)
  (unless (or *print-escape* *print-readably*)
    (when (and *print-condition-references*
               (reference-condition-references o))
      (format s "~&See also:~%")
      (pprint-logical-block (s nil :per-line-prefix "  ")
        (do* ((rs (reference-condition-references o) (cdr rs))
              (r (car rs) (car rs)))
             ((null rs))
          (print-reference r s)
          (unless (null (cdr rs))
            (terpri s)))))))

(define-condition simple-reference-error (reference-condition simple-error)
  ())

(define-condition simple-reference-warning (reference-condition simple-warning)
  ())

(define-condition arguments-out-of-domain-error
    (arithmetic-error reference-condition)
  ())

(define-condition duplicate-definition (reference-condition warning)
  ((name :initarg :name :reader duplicate-definition-name))
  (:report (lambda (c s)
             (format s "~@<Duplicate definition for ~S found in ~
                        one file.~@:>"
                     (duplicate-definition-name c))))
  (:default-initargs :references (list '(:ansi-cl :section (3 2 2 3)))))

(define-condition constant-modified (reference-condition warning)
  ((fun-name :initarg :fun-name :reader constant-modified-fun-name))
  (:report (lambda (c s)
             (format s "~@<Destructive function ~S called on ~
                        constant data.~@:>"
                     (constant-modified-fun-name c))))
  (:default-initargs :references (list '(:ansi-cl :special-operator quote)
                                       '(:ansi-cl :section (3 2 2 3)))))

(define-condition package-at-variance (reference-condition simple-warning)
  ()
  (:default-initargs :references (list '(:ansi-cl :macro defpackage))))

(define-condition defconstant-uneql (reference-condition error)
  ((name :initarg :name :reader defconstant-uneql-name)
   (old-value :initarg :old-value :reader defconstant-uneql-old-value)
   (new-value :initarg :new-value :reader defconstant-uneql-new-value))
  (:report
   (lambda (condition stream)
     (format stream
             "~@<The constant ~S is being redefined (from ~S to ~S)~@:>"
             (defconstant-uneql-name condition)
             (defconstant-uneql-old-value condition)
             (defconstant-uneql-new-value condition))))
  (:default-initargs :references (list '(:ansi-cl :macro defconstant)
                                       '(:sbcl :node "Idiosyncrasies"))))

(define-condition array-initial-element-mismatch
    (reference-condition simple-warning)
  ()
  (:default-initargs
      :references (list
                   '(:ansi-cl :function make-array)
                   '(:ansi-cl :function sb!xc:upgraded-array-element-type))))

(define-condition type-warning (reference-condition simple-warning)
  ()
  (:default-initargs :references (list '(:sbcl :node "Handling of Types"))))
(define-condition type-style-warning (reference-condition simple-style-warning)
  ()
  (:default-initargs :references (list '(:sbcl :node "Handling of Types"))))

(define-condition local-argument-mismatch (reference-condition simple-warning)
  ()
  (:default-initargs :references (list '(:ansi-cl :section (3 2 2 3)))))

(define-condition format-args-mismatch (reference-condition)
  ()
  (:default-initargs :references (list '(:ansi-cl :section (22 3 10 2)))))

(define-condition format-too-few-args-warning
    (format-args-mismatch simple-warning)
  ())
(define-condition format-too-many-args-warning
    (format-args-mismatch simple-style-warning)
  ())

(define-condition implicit-generic-function-warning (style-warning)
  ((name :initarg :name :reader implicit-generic-function-name))
  (:report
   (lambda (condition stream)
     (let ((*package* (find-package :keyword)))
       (format stream "~@<Implicitly creating new generic function ~S.~:@>"
               (implicit-generic-function-name condition))))))

(define-condition extension-failure (reference-condition simple-error)
  ())

(define-condition structure-initarg-not-keyword
    (reference-condition simple-style-warning)
  ()
  (:default-initargs :references (list '(:ansi-cl :section (2 4 8 13)))))

#!+sb-package-locks
(progn

(define-condition package-lock-violation (package-error
                                          reference-condition
                                          simple-condition)
  ((current-package :initform *package*
                    :reader package-lock-violation-in-package))
  (:report
   (lambda (condition stream)
     (let ((control (simple-condition-format-control condition))
           (error-package (package-name (package-error-package condition)))
           (current-package (package-name (package-lock-violation-in-package condition))))
       (if control
           (apply #'format stream
                  (format nil "~~@<Lock on package ~A violated when ~A while in package ~A.~~:@>"
                          error-package
                          control
                          current-package)
                  (simple-condition-format-arguments condition))
           (format stream "~@<Lock on package ~A violated while in package ~A.~:@>"
                   error-package
                   current-package)))))
  ;; no :default-initargs -- reference-stuff provided by the
  ;; signalling form in target-package.lisp
  #!+sb-doc
  (:documentation
   "Subtype of CL:PACKAGE-ERROR. A subtype of this error is signalled
when a package-lock is violated."))

(define-condition package-locked-error (package-lock-violation) ()
  #!+sb-doc
  (:documentation
   "Subtype of SB-EXT:PACKAGE-LOCK-VIOLATION. An error of this type is
signalled when an operation on a package violates a package lock."))

(define-condition symbol-package-locked-error (package-lock-violation)
  ((symbol :initarg :symbol :reader package-locked-error-symbol))
  #!+sb-doc
  (:documentation
   "Subtype of SB-EXT:PACKAGE-LOCK-VIOLATION. An error of this type is
signalled when an operation on a symbol violates a package lock. The
symbol that caused the violation is accessed by the function
SB-EXT:PACKAGE-LOCKED-ERROR-SYMBOL."))

) ; progn

(define-condition undefined-alien-error (cell-error) ()
  (:report
   (lambda (condition stream)
     (if (slot-boundp condition 'name)
         (format stream "Undefined alien: ~S" (cell-error-name condition))
         (format stream "Undefined alien symbol.")))))

(define-condition undefined-alien-variable-error (undefined-alien-error) ()
  (:report
   (lambda (condition stream)
     (declare (ignore condition))
     (format stream "Attempt to access an undefined alien variable."))))

(define-condition undefined-alien-function-error (undefined-alien-error) ()
  (:report
   (lambda (condition stream)
     (declare (ignore condition))
     (format stream "Attempt to call an undefined alien function."))))


  various other ( not specified by ANSI ) CONDITIONs
;;;;
;;;; These might logically belong in other files; they're here, after
;;;; setup of CONDITION machinery, only because that makes it easier to
;;;; get cold init to work.

;;; OAOOM warning: see cross-condition.lisp
(define-condition encapsulated-condition (condition)
  ((condition :initarg :condition :reader encapsulated-condition)))

   : a condition for floating point errors when we ca n't or
  wo n't figure out what type they are . ( In FreeBSD and OpenBSD we
  do n't know how , at least as of sbcl-0.6.7 ; in Linux we probably
;;; know how but the old code was broken by the conversion to POSIX
  signal handling and has n't been fixed as of sbcl-0.6.7 . )
;;;
;;; FIXME: Perhaps this should also be a base class for all
;;; floating point exceptions?
(define-condition floating-point-exception (arithmetic-error)
  ((flags :initarg :traps
          :initform nil
          :reader floating-point-exception-traps))
  (:report (lambda (condition stream)
             (format stream
                     "An arithmetic error ~S was signalled.~%"
                     (type-of condition))
             (let ((traps (floating-point-exception-traps condition)))
               (if traps
                   (format stream
                           "Trapping conditions are: ~%~{ ~S~^~}~%"
                           traps)
                   (write-line
                    "No traps are enabled? How can this be?"
                    stream))))))

(define-condition invalid-array-index-error (type-error)
  ((array :initarg :array :reader invalid-array-index-error-array)
   (axis :initarg :axis :reader invalid-array-index-error-axis))
  (:report
   (lambda (condition stream)
     (let ((array (invalid-array-index-error-array condition)))
       (format stream "Index ~W out of bounds for ~@[axis ~W of ~]~S, ~
                       should be nonnegative and <~W."
               (type-error-datum condition)
               (when (> (array-rank array) 1)
                 (invalid-array-index-error-axis condition))
               (type-of array)
  Extract the bound from ( INTEGER 0 ( BOUND ) )
               (caaddr (type-error-expected-type condition)))))))

(define-condition invalid-array-error (reference-condition type-error) ()
  (:report
   (lambda (condition stream)
     (let ((*print-array* nil))
       (format stream
               "~@<Displaced array originally of type ~S has been invalidated ~
                due its displaced-to array ~S having become too small to hold ~
                it: the displaced array's dimensions have all been set to zero ~
                to trap accesses to it.~:@>"
               (type-error-expected-type condition)
               (array-displacement (type-error-datum condition))))))
  (:default-initargs
      :references
      (list '(:ansi-cl :function adjust-array))))

(define-condition index-too-large-error (type-error)
  ()
  (:report
   (lambda (condition stream)
     (format stream
             "The index ~S is too large."
             (type-error-datum condition)))))

(define-condition bounding-indices-bad-error (reference-condition type-error)
  ((object :reader bounding-indices-bad-object :initarg :object))
  (:report
   (lambda (condition stream)
     (let* ((datum (type-error-datum condition))
            (start (car datum))
            (end (cdr datum))
            (object (bounding-indices-bad-object condition)))
       (etypecase object
         (sequence
          (format stream
                  "The bounding indices ~S and ~S are bad ~
                   for a sequence of length ~S."
                  start end (length object)))
         (array
          ;; from WITH-ARRAY-DATA
          (format stream
                  "The START and END parameters ~S and ~S are ~
                   bad for an array of total size ~S."
                  start end (array-total-size object)))))))
  (:default-initargs
      :references
      (list '(:ansi-cl :glossary "bounding index designator")
            '(:ansi-cl :issue "SUBSEQ-OUT-OF-BOUNDS:IS-AN-ERROR"))))

(define-condition nil-array-accessed-error (reference-condition type-error)
  ()
  (:report (lambda (condition stream)
             (declare (ignore condition))
             (format stream
                     "An attempt to access an array of element-type ~
                      NIL was made.  Congratulations!")))
  (:default-initargs
      :references (list '(:ansi-cl :function sb!xc:upgraded-array-element-type)
                        '(:ansi-cl :section (15 1 2 1))
                        '(:ansi-cl :section (15 1 2 2)))))

(define-condition namestring-parse-error (parse-error)
  ((complaint :reader namestring-parse-error-complaint :initarg :complaint)
   (args :reader namestring-parse-error-args :initarg :args :initform nil)
   (namestring :reader namestring-parse-error-namestring :initarg :namestring)
   (offset :reader namestring-parse-error-offset :initarg :offset))
  (:report
   (lambda (condition stream)
     (format stream
             "parse error in namestring: ~?~%  ~A~%  ~V@T^"
             (namestring-parse-error-complaint condition)
             (namestring-parse-error-args condition)
             (namestring-parse-error-namestring condition)
             (namestring-parse-error-offset condition)))))

(define-condition simple-package-error (simple-condition package-error) ())

(define-condition simple-reader-package-error (simple-reader-error package-error) ())

(define-condition reader-eof-error (end-of-file)
  ((context :reader reader-eof-error-context :initarg :context))
  (:report
   (lambda (condition stream)
     (format stream
             "unexpected end of file on ~S ~A"
             (stream-error-stream condition)
             (reader-eof-error-context condition)))))

(define-condition reader-impossible-number-error (simple-reader-error)
  ((error :reader reader-impossible-number-error-error :initarg :error))
  (:report
   (lambda (condition stream)
     (let ((error-stream (stream-error-stream condition)))
       (format stream
               "READER-ERROR ~@[at ~W ~]on ~S:~%~?~%Original error: ~A"
               (file-position-or-nil-for-error error-stream) error-stream
               (simple-condition-format-control condition)
               (simple-condition-format-arguments condition)
               (reader-impossible-number-error-error condition))))))

(define-condition standard-readtable-modified-error (reference-condition error)
  ((operation :initarg :operation :reader standard-readtable-modified-operation))
  (:report (lambda (condition stream)
             (format stream "~S would modify the standard readtable."
                     (standard-readtable-modified-operation condition))))
  (:default-initargs :references `((:ansi-cl :section (2 1 1 2))
                                   (:ansi-cl :glossary "standard readtable"))))

(define-condition standard-pprint-dispatch-table-modified-error
    (reference-condition error)
  ((operation :initarg :operation
              :reader standard-pprint-dispatch-table-modified-operation))
  (:report (lambda (condition stream)
             (format stream "~S would modify the standard pprint dispatch table."
                     (standard-pprint-dispatch-table-modified-operation
                      condition))))
  (:default-initargs
      :references `((:ansi-cl :glossary "standard pprint dispatch table"))))

(define-condition timeout (serious-condition)
  ((seconds :initarg :seconds :initform nil :reader timeout-seconds))
  (:report (lambda (condition stream)
             (format stream "Timeout occurred~@[ after ~A seconds~]."
                     (timeout-seconds condition)))))

(define-condition io-timeout (stream-error timeout)
  ((direction :reader io-timeout-direction :initarg :direction))
  (:report
   (lambda (condition stream)
     (declare (type stream stream))
     (format stream
             "I/O timeout while doing ~(~A~) on ~S."
             (io-timeout-direction condition)
             (stream-error-stream condition)))))

(define-condition deadline-timeout (timeout) ()
  (:report (lambda (condition stream)
             (format stream "A deadline was reached after ~A seconds."
                     (timeout-seconds condition)))))

(define-condition declaration-type-conflict-error (reference-condition
                                                   simple-error)
  ()
  (:default-initargs
      :format-control "symbol ~S cannot be both the name of a type and the name of a declaration"
    :references (list '(:ansi-cl :section (3 8 21)))))

;;; Single stepping conditions

(define-condition step-condition ()
  ((form :initarg :form :reader step-condition-form))

  #!+sb-doc
  (:documentation "Common base class of single-stepping conditions.
STEP-CONDITION-FORM holds a string representation of the form being
stepped."))

#!+sb-doc
(setf (fdocumentation 'step-condition-form 'function)
      "Form associated with the STEP-CONDITION.")

(define-condition step-form-condition (step-condition)
  ((args :initarg :args :reader step-condition-args))
  (:report
   (lambda (condition stream)
     (let ((*print-circle* t)
           (*print-pretty* t)
           (*print-readably* nil))
       (format stream
                 "Evaluating call:~%~<  ~@;~A~:>~%~
                  ~:[With arguments:~%~{  ~S~%~}~;With unknown arguments~]~%"
               (list (step-condition-form condition))
               (eq (step-condition-args condition) :unknown)
               (step-condition-args condition)))))
  #!+sb-doc
  (:documentation "Condition signalled by code compiled with
single-stepping information when about to execute a form.
STEP-CONDITION-FORM holds the form, STEP-CONDITION-PATHNAME holds the
pathname of the original file or NIL, and STEP-CONDITION-SOURCE-PATH
holds the source-path to the original form within that file or NIL.
Associated with this condition are always the restarts STEP-INTO,
STEP-NEXT, and STEP-CONTINUE."))

(define-condition step-result-condition (step-condition)
  ((result :initarg :result :reader step-condition-result)))

#!+sb-doc
(setf (fdocumentation 'step-condition-result 'function)
      "Return values associated with STEP-VALUES-CONDITION as a list,
or the variable value associated with STEP-VARIABLE-CONDITION.")

(define-condition step-values-condition (step-result-condition)
  ()
  #!+sb-doc
  (:documentation "Condition signalled by code compiled with
single-stepping information after executing a form.
STEP-CONDITION-FORM holds the form, and STEP-CONDITION-RESULT holds
the values returned by the form as a list. No associated restarts."))

(define-condition step-finished-condition (step-condition)
  ()
  (:report
   (lambda (condition stream)
     (declare (ignore condition))
     (format stream "Returning from STEP")))
  #!+sb-doc
  (:documentation "Condition signaled when STEP returns."))

;;; A knob for muffling warnings, mostly for use while loading files.
(defvar *muffled-warnings* 'uninteresting-redefinition
  "A type that ought to specify a subtype of WARNING.  Whenever a
warning is signaled, if the warning if of this type and is not
handled by any other handler, it will be muffled.")

;;; Various STYLE-WARNING signaled in the system.
;; For the moment, we're only getting into the details for function
  redefinitions , but other redefinitions could be done later
;; (e.g. methods).
(define-condition redefinition-warning (style-warning)
  ((name
    :initarg :name
    :reader redefinition-warning-name)
   (new-location
    :initarg :new-location
    :reader redefinition-warning-new-location)))

(define-condition function-redefinition-warning (redefinition-warning)
  ((new-function
    :initarg :new-function
    :reader function-redefinition-warning-new-function)))

(define-condition redefinition-with-defun (function-redefinition-warning)
  ()
  (:report (lambda (warning stream)
             (format stream "redefining ~/sb-impl::print-symbol-with-prefix/ ~
                             in DEFUN"
                     (redefinition-warning-name warning)))))

(define-condition redefinition-with-defmacro (function-redefinition-warning)
  ()
  (:report (lambda (warning stream)
             (format stream "redefining ~/sb-impl::print-symbol-with-prefix/ ~
                             in DEFMACRO"
                     (redefinition-warning-name warning)))))

(define-condition redefinition-with-defgeneric (redefinition-warning)
  ()
  (:report (lambda (warning stream)
             (format stream "redefining ~/sb-impl::print-symbol-with-prefix/ ~
                             in DEFGENERIC"
                     (redefinition-warning-name warning)))))

(define-condition redefinition-with-defmethod (redefinition-warning)
  ((qualifiers :initarg :qualifiers
               :reader redefinition-with-defmethod-qualifiers)
   (specializers :initarg :specializers
                 :reader redefinition-with-defmethod-specializers)
   (new-location :initarg :new-location
                 :reader redefinition-with-defmethod-new-location)
   (old-method :initarg :old-method
               :reader redefinition-with-defmethod-old-method))
  (:report (lambda (warning stream)
             (format stream "redefining ~S~{ ~S~} ~S in DEFMETHOD"
                     (redefinition-warning-name warning)
                     (redefinition-with-defmethod-qualifiers warning)
                     (redefinition-with-defmethod-specializers warning)))))

  Deciding which redefinitions are " interesting " .

(defun function-file-namestring (function)
  #!+sb-eval
  (when (typep function 'sb!eval:interpreted-function)
    (return-from function-file-namestring
      (sb!c:definition-source-location-namestring
          (sb!eval:interpreted-function-source-location function))))
  (let* ((fun (sb!kernel:%fun-fun function))
         (code (sb!kernel:fun-code-header fun))
         (debug-info (sb!kernel:%code-debug-info code))
         (debug-source (when debug-info
                         (sb!c::debug-info-source debug-info)))
         (namestring (when debug-source
                       (sb!c::debug-source-namestring debug-source))))
    namestring))

(defun interesting-function-redefinition-warning-p (warning old)
  (let ((new (function-redefinition-warning-new-function warning))
        (source-location (redefinition-warning-new-location warning)))
    (or
  Compiled->Interpreted is interesting .
     (and (typep old 'compiled-function)
          (typep new '(not compiled-function)))
     ;; FIN->Regular is interesting.
     (and (typep old 'funcallable-instance)
          (typep new '(not funcallable-instance)))
     ;; Different file or unknown location is interesting.
     (let* ((old-namestring (function-file-namestring old))
            (new-namestring
             (or (function-file-namestring new)
                 (when source-location
                   (sb!c::definition-source-location-namestring source-location)))))
       (and (or (not old-namestring)
                (not new-namestring)
                (not (string= old-namestring new-namestring))))))))

(defun uninteresting-ordinary-function-redefinition-p (warning)
  (and
  There 's garbage in various places when the first DEFUN runs in
   ;; cold-init.
   sb!kernel::*cold-init-complete-p*
   (typep warning 'redefinition-with-defun)
   ;; Shared logic.
   (let ((name (redefinition-warning-name warning)))
     (not (interesting-function-redefinition-warning-p
           warning (or (fdefinition name) (macro-function name)))))))

(defun uninteresting-macro-redefinition-p (warning)
  (and
   (typep warning 'redefinition-with-defmacro)
   ;; Shared logic.
   (let ((name (redefinition-warning-name warning)))
     (not (interesting-function-redefinition-warning-p
           warning (or (macro-function name) (fdefinition name)))))))

(defun uninteresting-generic-function-redefinition-p (warning)
  (and
   (typep warning 'redefinition-with-defgeneric)
  Ca n't use the shared logic above , since GF 's do n't get a " new "
  definition -- rather the FIN - FUNCTION is set .
   (let* ((name (redefinition-warning-name warning))
          (old (fdefinition name))
          (old-location (when (typep old 'generic-function)
                          (sb!pcl::definition-source old)))
          (old-namestring (when old-location
                            (sb!c:definition-source-location-namestring old-location)))
          (new-location (redefinition-warning-new-location warning))
          (new-namestring (when new-location
                           (sb!c:definition-source-location-namestring new-location))))
     (and old-namestring
          new-namestring
          (string= old-namestring new-namestring)))))

(defun uninteresting-method-redefinition-p (warning)
  (and
   (typep warning 'redefinition-with-defmethod)
  Ca n't use the shared logic above , since GF 's do n't get a " new "
  definition -- rather the FIN - FUNCTION is set .
   (let* ((old-method (redefinition-with-defmethod-old-method warning))
          (old-location (sb!pcl::definition-source old-method))
          (old-namestring (when old-location
                            (sb!c:definition-source-location-namestring old-location)))
          (new-location (redefinition-warning-new-location warning))
          (new-namestring (when new-location
                            (sb!c:definition-source-location-namestring new-location))))
         (and new-namestring
              old-namestring
              (string= new-namestring old-namestring)))))

(deftype uninteresting-redefinition ()
  '(or (satisfies uninteresting-ordinary-function-redefinition-p)
       (satisfies uninteresting-macro-redefinition-p)
       (satisfies uninteresting-generic-function-redefinition-p)
       (satisfies uninteresting-method-redefinition-p)))

(define-condition redefinition-with-deftransform (redefinition-warning)
  ((transform :initarg :transform
              :reader redefinition-with-deftransform-transform))
  (:report (lambda (warning stream)
             (format stream "Overwriting ~S"
                     (redefinition-with-deftransform-transform warning)))))

;;; Various other STYLE-WARNINGS
(define-condition dubious-asterisks-around-variable-name
    (style-warning simple-condition)
  ()
  (:report (lambda (warning stream)
             (format stream "~@?, even though the name follows~@
the usual naming convention (names like *FOO*) for special variables"
                     (simple-condition-format-control warning)
                     (simple-condition-format-arguments warning)))))

(define-condition asterisks-around-lexical-variable-name
    (dubious-asterisks-around-variable-name)
  ())

(define-condition asterisks-around-constant-variable-name
    (dubious-asterisks-around-variable-name)
  ())

  We call this UNDEFINED - ALIEN - STYLE - WARNING because there are some
;; subclasses of ERROR above having to do with undefined aliens.
(define-condition undefined-alien-style-warning (style-warning)
  ((symbol :initarg :symbol :reader undefined-alien-symbol))
  (:report (lambda (warning stream)
             (format stream "Undefined alien: ~S"
                     (undefined-alien-symbol warning)))))

#!+sb-eval
(define-condition lexical-environment-too-complex (style-warning)
  ((form :initarg :form :reader lexical-environment-too-complex-form)
   (lexenv :initarg :lexenv :reader lexical-environment-too-complex-lexenv))
  (:report (lambda (warning stream)
             (format stream
                     "~@<Native lexical environment too complex for ~
                         SB-EVAL to evaluate ~S, falling back to ~
                         SIMPLE-EVAL-IN-LEXENV.  Lexenv: ~S~:@>"
                     (lexical-environment-too-complex-form warning)
                     (lexical-environment-too-complex-lexenv warning)))))

;; Although this has -ERROR- in the name, it's just a STYLE-WARNING.
(define-condition character-decoding-error-in-comment (style-warning)
  ((stream :initarg :stream :reader decoding-error-in-comment-stream)
   (position :initarg :position :reader decoding-error-in-comment-position))
  (:report (lambda (warning stream)
             (format stream
                      "Character decoding error in a ~A-comment at ~
                      position ~A reading source stream ~A, ~
                      resyncing."
                      (decoding-error-in-comment-macro warning)
                      (decoding-error-in-comment-position warning)
                      (decoding-error-in-comment-stream warning)))))

(define-condition character-decoding-error-in-macro-char-comment
    (character-decoding-error-in-comment)
  ((char :initform #\; :initarg :char
         :reader character-decoding-error-in-macro-char-comment-char)))

(define-condition character-decoding-error-in-dispatch-macro-char-comment
    (character-decoding-error-in-comment)
  ;; ANSI doesn't give a way for a reader function invoked by a
  ;; dispatch macro character to determine which dispatch character
  was used , so if a user wants to signal one of these from a custom
  ;; comment reader, he'll have to supply the :DISP-CHAR himself.
  ((disp-char :initform #\# :initarg :disp-char
              :reader character-decoding-error-in-macro-char-comment-disp-char)
   (sub-char :initarg :sub-char
             :reader character-decoding-error-in-macro-char-comment-sub-char)))

(defun decoding-error-in-comment-macro (warning)
  (etypecase warning
    (character-decoding-error-in-macro-char-comment
     (character-decoding-error-in-macro-char-comment-char warning))
    (character-decoding-error-in-dispatch-macro-char-comment
     (format
      nil "~C~C"
      (character-decoding-error-in-macro-char-comment-disp-char warning)
      (character-decoding-error-in-macro-char-comment-sub-char warning)))))

(define-condition deprecated-eval-when-situations (style-warning)
  ((situations :initarg :situations
               :reader deprecated-eval-when-situations-situations))
  (:report (lambda (warning stream)
             (format stream "using deprecated EVAL-WHEN situation names~{ ~S~}"
                     (deprecated-eval-when-situations-situations warning)))))

(define-condition proclamation-mismatch (style-warning)
  ((name :initarg :name :reader proclamation-mismatch-name)
   (old :initarg :old :reader proclamation-mismatch-old)
   (new :initarg :new :reader proclamation-mismatch-new)))

(define-condition type-proclamation-mismatch (proclamation-mismatch)
  ()
  (:report (lambda (warning stream)
             (format stream
                     "The new TYPE proclamation~% ~S for ~S does not ~
                     match the old TYPE proclamation ~S"
                     (proclamation-mismatch-new warning)
                     (proclamation-mismatch-name warning)
                     (proclamation-mismatch-old warning)))))

(define-condition ftype-proclamation-mismatch (proclamation-mismatch)
  ()
  (:report (lambda (warning stream)
             (format stream
                     "The new FTYPE proclamation~% ~S for ~S does not ~
                     match the old FTYPE proclamation ~S"
                     (proclamation-mismatch-new warning)
                     (proclamation-mismatch-name warning)
                     (proclamation-mismatch-old warning)))))

;;;; deprecation conditions

(define-condition deprecation-condition ()
  ((name :initarg :name :reader deprecated-name)
   (replacements :initarg :replacements :reader deprecated-name-replacements)
   (since :initarg :since :reader deprecated-since)
   (runtime-error :initarg :runtime-error :reader deprecated-name-runtime-error)))

(def!method print-object ((condition deprecation-condition) stream)
  (let ((*package* (find-package :keyword)))
    (if *print-escape*
        (print-unreadable-object (condition stream :type t)
          (apply #'format
                 stream "~S is deprecated.~
                         ~#[~; Use ~S instead.~; ~
                               Use ~S or ~S instead.~:; ~
                               Use~@{~#[~; or~] ~S~^,~} instead.~]"
                  (deprecated-name condition)
                  (deprecated-name-replacements condition)))
        (apply #'format
               stream "~@<~S has been deprecated as of SBCL ~A.~
                       ~#[~; Use ~S instead.~; ~
                             Use ~S or ~S instead.~:; ~
                             Use~@{~#[~; or~] ~S~^,~:_~} instead.~]~:@>"
                (deprecated-name condition)
                (deprecated-since condition)
                (deprecated-name-replacements condition)))))

(define-condition early-deprecation-warning (style-warning deprecation-condition)
  ())

(def!method print-object :after ((warning early-deprecation-warning) stream)
  (unless *print-escape*
    (let ((*package* (find-package :keyword)))
      (format stream "~%~@<~:@_In future SBCL versions ~S will signal a full warning ~
                      at compile-time.~:@>"
              (deprecated-name warning)))))

(define-condition late-deprecation-warning (warning deprecation-condition)
  ())

(def!method print-object :after ((warning late-deprecation-warning) stream)
  (unless *print-escape*
    (when (deprecated-name-runtime-error warning)
      (let ((*package* (find-package :keyword)))
        (format stream "~%~@<~:@_In future SBCL versions ~S will signal a runtime error.~:@>"
                (deprecated-name warning))))))

(define-condition final-deprecation-warning (warning deprecation-condition)
  ())

(def!method print-object :after ((warning final-deprecation-warning) stream)
  (unless *print-escape*
    (when (deprecated-name-runtime-error warning)
      (let ((*package* (find-package :keyword)))
        (format stream "~%~@<~:@_An error will be signaled at runtime for ~S.~:@>"
                (deprecated-name warning))))))

(define-condition deprecation-error (error deprecation-condition)
  ())

;;;; restart definitions

(define-condition abort-failure (control-error) ()
  (:report
   "An ABORT restart was found that failed to transfer control dynamically."))

(defun abort (&optional condition)
  #!+sb-doc
  "Transfer control to a restart named ABORT, signalling a CONTROL-ERROR if
   none exists."
  (invoke-restart (find-restart-or-control-error 'abort condition))
  ABORT signals an error in case there was a restart named 
  ;; that did not transfer control dynamically. This could happen with
  RESTART - BIND .
  (error 'abort-failure))

(defun muffle-warning (&optional condition)
  #!+sb-doc
  "Transfer control to a restart named MUFFLE-WARNING, signalling a
   CONTROL-ERROR if none exists."
  (invoke-restart (find-restart-or-control-error 'muffle-warning condition)))

(defun try-restart (name condition &rest arguments)
  (let ((restart (find-restart name condition)))
    (when restart
      (apply #'invoke-restart restart arguments))))

(macrolet ((define-nil-returning-restart (name args doc)
             #!-sb-doc (declare (ignore doc))
             `(defun ,name (,@args &optional condition)
                #!+sb-doc ,doc
                (try-restart ',name condition ,@args))))
  (define-nil-returning-restart continue ()
    "Transfer control to a restart named CONTINUE, or return NIL if none exists.")
  (define-nil-returning-restart store-value (value)
    "Transfer control and VALUE to a restart named STORE-VALUE, or
return NIL if none exists.")
  (define-nil-returning-restart use-value (value)
    "Transfer control and VALUE to a restart named USE-VALUE, or
return NIL if none exists.")
  (define-nil-returning-restart print-unreadably ()
    "Transfer control to a restart named SB-EXT:PRINT-UNREADABLY, or
return NIL if none exists."))

;;; single-stepping restarts

(macrolet ((def (name doc)
               #!-sb-doc (declare (ignore doc))
               `(defun ,name (condition)
                 #!+sb-doc ,doc
                 (invoke-restart (find-restart-or-control-error ',name condition)))))
  (def step-continue
      "Transfers control to the STEP-CONTINUE restart associated with
the condition, continuing execution without stepping. Signals a
CONTROL-ERROR if the restart does not exist.")
  (def step-next
      "Transfers control to the STEP-NEXT restart associated with the
condition, executing the current form without stepping and continuing
stepping with the next form. Signals CONTROL-ERROR is the restart does
not exists.")
  (def step-into
      "Transfers control to the STEP-INTO restart associated with the
condition, stepping into the current form. Signals a CONTROL-ERROR is
the restart does not exist."))

  Compiler macro magic

(define-condition compiler-macro-keyword-problem ()
  ((argument :initarg :argument :reader compiler-macro-keyword-argument))
  (:report (lambda (condition stream)
             (format stream "~@<Argument ~S in keyword position is not ~
                             a self-evaluating symbol, preventing compiler-macro ~
                             expansion.~@:>"
                     (compiler-macro-keyword-argument condition)))))

(/show0 "condition.lisp end of file")

 come late (mostly related to the CONDITION class itself)

 more information.

 public domain. The software is in the public domain and is
 provided with absolutely no warranty. See the COPYING and CREDITS
 files for more information.
 the CONDITION class
 list of CONDITION-SLOT structures for the direct slots of this
 class
 list of CONDITION-SLOT structures for all of the effective class
 slots of this class
 list of alternating initargs and initforms
 class precedence list as a list of CLASS objects, with all
 non-CONDITION classes removed
 a list of all the effective instance allocation slots of this
 Values for these slots must be computed in the dynamic
 environment of MAKE-CONDITION.
 list of all applicable initargs
 names of reader and writer functions
 If this is a function, call it with no args. Otherwise, it's the
 actual value.
 If ALLOCATION is :CLASS, this is a cons whose car holds the value.
 slot documentation
 have themselves listed in their CPLs. This behavior is inherited
 FIND-CLASSOID for constant class names
 which creates fast but
 non-cold-loadable, non-compact code. In
 this context, we'd rather have compact,
 FIND-CLASSOID for constant class
 names which creates fast but
 non-cold-loadable, non-compact
 code. In this context, we'd
 rather have compact,
 FIXME: Does this do the right thing in case of multiple
 inheritance? A quick look at DEFINE-CONDITION didn't make
 it obvious what ANSI intends to be done in the case of
 multiple inheritance, so it's not actually clear what the
 right thing is..
   Condition reporting is mediated through the PRINT-OBJECT method
   for the condition type in question, with *PRINT-ESCAPE* always
   being nil. Specifying (:REPORT REPORT-NAME) in the definition of
   a condition type C is equivalent to:
       (if *print-escape* (call-next-method) (report-name x stream)))
 The current code doesn't seem to quite match that.
   superclasses in define-condition call!
 slots of CONDITION objects
 MAKE-CONDITION
 Note: ANSI specifies no exceptional situations in this function.
 signalling simple-type-error would not be wrong.
 Set any class slots with initargs present in this call.
 Default any slots with non-constant defaults now.
 DEFINE-CONDITION
 names which creates fast but non-cold-loadable, non-compact
 code. In this context, we'd rather have compact, cold-loadable
 Compute the effective slots of CLASS, copying inherited slots and
 destructively modifying direct slots.

 FIXME: It'd be nice to explain why it's OK to destructively modify
 direct slots. Presumably it follows from the semantics of
 inheritance and redefinition of conditions, but finding the cite
 and documenting it here would be good. (Or, if this is not in fact
 ANSI-compliant, fixing it would also be good.:-)
 Early definitions of slot accessor creators.

 to specify any of them, and we cannot support it before end of
 GFs only at the end of building.
 Set up reader and writer functions.
 Compute effective slots and set up the class and hairy slots
 (subsets of the effective slots.)
 This needs to be after %DEFINE-CONDITION in case :REPORT
 is a lambda referring to condition slot accessors:
 they're not proclaimed as functions before it has run if
 Can't have a function called SIMPLE-TYPE-ERROR or TYPE-ERROR...
 a READER-ERROR whose REPORTing is controlled by FORMAT-CONTROL and

 (Inheriting CL:SIMPLE-CONDITION here isn't quite consistent with
 the spec, but if not, it'd be straightforward to do our own
 DEFINE-CONDITION SB-INT:SIMPLISTIC-CONDITION with
 FORMAT-CONTROL and FORMAT-ARGS slots, and use that condition in
 base REPORTing of a READER-ERROR

 When SIMPLE, we expect and use SIMPLE-CONDITION-ish FORMAT-CONTROL
 and FORMAT-ARGS slots.

 Note that we don't make any serious effort to use this condition
 will just end up as ordinary TYPE-ERROR or invalid index error,
 because the signalling code has no good way to know that the
 this condition is appropriate, reusing boilerplate and helping
 or there might be a bug ~
 a condition for use in stubs for operations which aren't supported
 on some platforms

   (defun load-foreign (&rest rest)
     (error 'unsupported-operator :name 'load-foreign))
   (defun load-foreign ... actual definition ...)
 By signalling a standard condition in this case, we make it
 (Before this condition was defined, test code tried to deal with
 this by checking for FBOUNDP, but that didn't work reliably. In
 LOAD-FOREIGN in the wrong package, so it was unFBOUNDP even on
 architectures where it was supposed to be supported, and the
 regression tests cheerfully passed because they assumed that
 unFBOUNDPness meant they were running on an system which didn't
 support the extension.)
 (:ansi-cl :function remove)
 (:ansi-cl :section (a b c))
 (:ansi-cl :glossary "similar")


 FIXME: this is not the right place for this.
 no :default-initargs -- reference-stuff provided by the
 signalling form in target-package.lisp
 progn

 These might logically belong in other files; they're here, after
 setup of CONDITION machinery, only because that makes it easier to
 get cold init to work.
 OAOOM warning: see cross-condition.lisp
 in Linux we probably
 know how but the old code was broken by the conversion to POSIX

 FIXME: Perhaps this should also be a base class for all
 floating point exceptions?
 from WITH-ARRAY-DATA
 Single stepping conditions
~A~:>~%~
With unknown arguments~]~%"
 A knob for muffling warnings, mostly for use while loading files.
 Various STYLE-WARNING signaled in the system.
 For the moment, we're only getting into the details for function
 (e.g. methods).
 FIN->Regular is interesting.
 Different file or unknown location is interesting.
 cold-init.
 Shared logic.
 Shared logic.
 Various other STYLE-WARNINGS
 subclasses of ERROR above having to do with undefined aliens.
 Although this has -ERROR- in the name, it's just a STYLE-WARNING.
 :initarg :char
 ANSI doesn't give a way for a reader function invoked by a
 dispatch macro character to determine which dispatch character
 comment reader, he'll have to supply the :DISP-CHAR himself.
 deprecation conditions
 Use ~S instead.~; ~
 ~
 or~] ~S~^,~} instead.~]"
 Use ~S instead.~; ~
 ~
 or~] ~S~^,~:_~} instead.~]~:@>"
 restart definitions
 that did not transfer control dynamically. This could happen with
 single-stepping restarts
  stuff originally from CMU CL 's error.lisp which can or should

  This software is part of the SBCL system . See the README file for
  This software is derived from the CMU CL system , which was
  written at Carnegie Mellon University and released into the

(in-package "SB!KERNEL")


(/show0 "condition.lisp 20")

(eval-when (:compile-toplevel :load-toplevel :execute)

(/show0 "condition.lisp 24")

(def!struct (condition-classoid (:include classoid)
                                (:constructor make-condition-classoid))
  (slots nil :type list)
  (class-slots nil :type list)
  report function or NIL
  (report nil :type (or function null))
  (default-initargs () :type list)
  (cpl () :type list)
  class that have a non - constant initform or default - initarg .
  (hairy-slots nil :type list))

(/show0 "condition.lisp 49")

  EVAL - WHEN

(!defstruct-with-alternate-metaclass condition
  :slot-names (actual-initargs assigned-slots)
  :boa-constructor %make-condition-object
  :superclass-name t
  :metaclass-name condition-classoid
  :metaclass-constructor make-condition-classoid
  :dd-type structure)

(defun make-condition-object (actual-initargs)
  (%make-condition-object actual-initargs nil))

(defstruct (condition-slot (:copier nil))
  (name (missing-arg) :type symbol)
  (initargs (missing-arg) :type list)
  (readers (missing-arg) :type list)
  (writers (missing-arg) :type list)
  true if : INITFORM was specified
  (initform-p (missing-arg) :type (member t nil))
  (initform (missing-arg) :type t)
  allocation of this slot , or NIL until defaulted
  (allocation nil :type (member :instance :class nil))
  (cell nil :type (or cons null))
  (documentation nil :type (or string null)))

   : It 's not clear to me why CONDITION - CLASS has itself listed
  in its CPL , while other classes derived from CONDITION - CLASS do n't
  from CMU CL , and did n't seem to be explained there , and I have n't
  figured out whether it 's right . -- WHN 19990612
(eval-when (:compile-toplevel :load-toplevel :execute)
  (/show0 "condition.lisp 103")
  (let ((condition-class (locally
   : There 's a DEFTRANSFORM
  cold - loadable code . -- WHN 19990928
                           (declare (notinline find-classoid))
                           (find-classoid 'condition))))
    (setf (condition-classoid-cpl condition-class)
          (list condition-class)))
  (/show0 "condition.lisp 103"))

(setf (condition-classoid-report (locally
   : There 's a DEFTRANSFORM
  cold - loadable code . -- WHN
  19990928
                                   (declare (notinline find-classoid))
                                   (find-classoid 'condition)))
      (lambda (cond stream)
        (format stream "Condition ~S was signalled." (type-of cond))))

(eval-when (:compile-toplevel :load-toplevel :execute)

(defun find-condition-layout (name parent-types)
  (let* ((cpl (remove-duplicates
               (reverse
                (reduce #'append
                        (mapcar (lambda (x)
                                  (condition-classoid-cpl
                                   (find-classoid x)))
                                parent-types)))))
         (cond-layout (info :type :compiler-layout 'condition))
         (olayout (info :type :compiler-layout name))
         (new-inherits
          (order-layout-inherits (concatenate 'simple-vector
                                              (layout-inherits cond-layout)
                                              (mapcar #'classoid-layout cpl)))))
    (if (and olayout
             (not (mismatch (layout-inherits olayout) new-inherits)))
        olayout
        (make-layout :classoid (make-undefined-classoid name)
                     :inherits new-inherits
                     :depthoid -1
                     :length (layout-length cond-layout)))))

  EVAL - WHEN

  FIXME : ANSI 's definition of DEFINE - CONDITION says
      ( defmethod print - object ( ( x c ) stream )
(def!method print-object ((x condition) stream)
  (if *print-escape*
      (if (and (typep x 'simple-condition) (slot-value x 'format-control))
          (print-unreadable-object (x stream :type t :identity t)
            (write (simple-condition-format-control x)
                   :stream stream
                   :lines 1))
          (print-unreadable-object (x stream :type t :identity t)))
   : A comment from CMU CL here said
    7/13/98 BUG ? CPL is not sorted and results here depend on order of
      (dolist (class (condition-classoid-cpl (classoid-of x))
                     (error "no REPORT? shouldn't happen!"))
        (let ((report (condition-classoid-report class)))
          (when report
            (return (funcall report x stream)))))))


(defvar *empty-condition-slot* '(empty))

(defun find-slot-default (class slot)
  (let ((initargs (condition-slot-initargs slot))
        (cpl (condition-classoid-cpl class)))
    (dolist (class cpl)
      (let ((default-initargs (condition-classoid-default-initargs class)))
        (dolist (initarg initargs)
          (let ((val (getf default-initargs initarg *empty-condition-slot*)))
            (unless (eq val *empty-condition-slot*)
              (return-from find-slot-default
                           (if (functionp val)
                               (funcall val)
                               val)))))))

    (if (condition-slot-initform-p slot)
        (let ((initform (condition-slot-initform slot)))
          (if (functionp initform)
              (funcall initform)
              initform))
        (error "unbound condition slot: ~S" (condition-slot-name slot)))))

(defun find-condition-class-slot (condition-class slot-name)
  (dolist (sclass
           (condition-classoid-cpl condition-class)
           (error "There is no slot named ~S in ~S."
                  slot-name condition-class))
    (dolist (slot (condition-classoid-slots sclass))
      (when (eq (condition-slot-name slot) slot-name)
        (return-from find-condition-class-slot slot)))))

(defun condition-writer-function (condition new-value name)
  (dolist (cslot (condition-classoid-class-slots
                  (layout-classoid (%instance-layout condition)))
                 (setf (getf (condition-assigned-slots condition) name)
                       new-value))
    (when (eq (condition-slot-name cslot) name)
      (return (setf (car (condition-slot-cell cslot)) new-value)))))

(defun condition-reader-function (condition name)
  (let ((class (layout-classoid (%instance-layout condition))))
    (dolist (cslot (condition-classoid-class-slots class))
      (when (eq (condition-slot-name cslot) name)
        (return-from condition-reader-function
                     (car (condition-slot-cell cslot)))))
    (let ((val (getf (condition-assigned-slots condition) name
                     *empty-condition-slot*)))
      (if (eq val *empty-condition-slot*)
          (let ((actual-initargs (condition-actual-initargs condition))
                (slot (find-condition-class-slot class name)))
            (unless slot
              (error "missing slot ~S of ~S" name condition))
            (do ((initargs actual-initargs (cddr initargs)))
                ((endp initargs)
                 (setf (getf (condition-assigned-slots condition) name)
                       (find-slot-default class slot)))
              (when (member (car initargs) (condition-slot-initargs slot))
                (return-from condition-reader-function
                  (setf (getf (condition-assigned-slots condition)
                              name)
                        (cadr initargs))))))
          val))))


(defun make-condition (type &rest args)
  #!+sb-doc
  "Make an instance of a condition object using the specified initargs."
  (let* ((type (or (and (symbolp type) (find-classoid type nil))
                    type))
         (class (typecase type
                  (condition-classoid type)
                  (class
  Punt to CLOS .
                   (return-from make-condition
                     (apply #'make-instance type args)))
                  (classoid
                   (error 'simple-type-error
                          :datum type
                          :expected-type 'condition-class
                          :format-control "~S is not a condition class."
                          :format-arguments (list type)))
                  (t
                   (error 'simple-type-error
                          :datum type
                          :expected-type 'condition-class
                          :format-control
                          "~s doesn't designate a condition class."
                          :format-arguments (list type)))))
         (res (make-condition-object args)))
    (setf (%instance-layout res) (classoid-layout class))
    (dolist (cslot (condition-classoid-class-slots class))
      (dolist (initarg (condition-slot-initargs cslot))
        (let ((val (getf args initarg *empty-condition-slot*)))
          (unless (eq val *empty-condition-slot*)
            (setf (car (condition-slot-cell cslot)) val)))))
    (dolist (hslot (condition-classoid-hairy-slots class))
      (when (dolist (initarg (condition-slot-initargs hslot) t)
              (unless (eq (getf args initarg *empty-condition-slot*)
                          *empty-condition-slot*)
                (return nil)))
        (setf (getf (condition-assigned-slots res) (condition-slot-name hslot))
              (find-slot-default class hslot))))
    res))


(eval-when (:compile-toplevel :load-toplevel :execute)
(defun %compiler-define-condition (name direct-supers layout
                                   all-readers all-writers)
  (with-single-package-locked-error
      (:symbol name "defining ~A as a condition")
    (sb!xc:proclaim `(ftype (function (t) t) ,@all-readers))
    (sb!xc:proclaim `(ftype (function (t t) t) ,@all-writers))
    (multiple-value-bind (class old-layout)
        (insured-find-classoid name
                               #'condition-classoid-p
                               #'make-condition-classoid)
      (setf (layout-classoid layout) class)
      (setf (classoid-direct-superclasses class)
            (mapcar #'find-classoid direct-supers))
      (cond ((not old-layout)
             (register-layout layout))
            ((not *type-system-initialized*)
             (setf (layout-classoid old-layout) class)
             (setq layout old-layout)
             (unless (eq (classoid-layout class) layout)
               (register-layout layout)))
            ((redefine-layout-warning "current"
                                      old-layout
                                      "new"
                                      (layout-length layout)
                                      (layout-inherits layout)
                                      (layout-depthoid layout)
                                      (layout-n-untagged-slots layout))
             (register-layout layout :invalidate t))
            ((not (classoid-layout class))
             (register-layout layout)))

      (setf (layout-info layout)
            (locally
   : There 's a FIND - CLASS DEFTRANSFORM for constant class
  code . -- WHN 19990928
                (declare (notinline find-classoid))
              (layout-info (classoid-layout (find-classoid 'condition)))))

      (setf (find-classoid name) class)

  Initialize CPL slot .
      (setf (condition-classoid-cpl class)
            (remove-if-not #'condition-classoid-p
                           (std-compute-class-precedence-list class)))))
  (values))
  EVAL - WHEN

(defun compute-effective-slots (class)
  (collect ((res (copy-list (condition-classoid-slots class))))
    (dolist (sclass (cdr (condition-classoid-cpl class)))
      (dolist (sslot (condition-classoid-slots sclass))
        (let ((found (find (condition-slot-name sslot) (res)
                           :key #'condition-slot-name)))
          (cond (found
                 (setf (condition-slot-initargs found)
                       (union (condition-slot-initargs found)
                              (condition-slot-initargs sslot)))
                 (unless (condition-slot-initform-p found)
                   (setf (condition-slot-initform-p found)
                         (condition-slot-initform-p sslot))
                   (setf (condition-slot-initform found)
                         (condition-slot-initform sslot)))
                 (unless (condition-slot-allocation found)
                   (setf (condition-slot-allocation found)
                         (condition-slot-allocation sslot))))
                (t
                 (res (copy-structure sslot)))))))
    (res)))

  Slot accessors must be generic functions , but ANSI does not seem
  warm init . So we use ordinary functions inside SBCL , and switch to
(declaim (notinline install-condition-slot-reader
                    install-condition-slot-writer))
(defun install-condition-slot-reader (name condition slot-name)
  (declare (ignore condition))
  (setf (fdefinition name)
        (lambda (condition)
          (condition-reader-function condition slot-name))))
(defun install-condition-slot-writer (name condition slot-name)
  (declare (ignore condition))
  (setf (fdefinition name)
        (lambda (new-value condition)
          (condition-writer-function condition new-value slot-name))))

(defvar *define-condition-hooks* nil)

(defun %set-condition-report (name report)
  (setf (condition-classoid-report (find-classoid name))
        report))

(defun %define-condition (name parent-types layout slots documentation
                          default-initargs all-readers all-writers
                          source-location)
  (with-single-package-locked-error
      (:symbol name "defining ~A as a condition")
    (%compiler-define-condition name parent-types layout all-readers all-writers)
    (sb!c:with-source-location (source-location)
      (setf (layout-source-location layout)
            source-location))
    (let ((class (find-classoid name)))
      (setf (condition-classoid-slots class) slots)
      (setf (condition-classoid-default-initargs class) default-initargs)
      (setf (fdocumentation name 'type) documentation)

      (dolist (slot slots)

        (let ((slot-name (condition-slot-name slot)))
          (dolist (reader (condition-slot-readers slot))
            (install-condition-slot-reader reader name slot-name))
          (dolist (writer (condition-slot-writers slot))
            (install-condition-slot-writer writer name slot-name))))

      (let ((eslots (compute-effective-slots class))
            (e-def-initargs
             (reduce #'append
                     (mapcar #'condition-classoid-default-initargs
                           (condition-classoid-cpl class)))))
        (dolist (slot eslots)
          (ecase (condition-slot-allocation slot)
            (:class
             (unless (condition-slot-cell slot)
               (setf (condition-slot-cell slot)
                     (list (if (condition-slot-initform-p slot)
                               (let ((initform (condition-slot-initform slot)))
                                 (if (functionp initform)
                                     (funcall initform)
                                     initform))
                               *empty-condition-slot*))))
             (push slot (condition-classoid-class-slots class)))
            ((:instance nil)
             (setf (condition-slot-allocation slot) :instance)
             (when (or (functionp (condition-slot-initform slot))
                       (dolist (initarg (condition-slot-initargs slot) nil)
                         (when (functionp (getf e-def-initargs initarg))
                           (return t))))
               (push slot (condition-classoid-hairy-slots class)))))))
      (when (boundp '*define-condition-hooks*)
        (dolist (fun *define-condition-hooks*)
          (funcall fun class))))
    name))

(defmacro define-condition (name (&rest parent-types) (&rest slot-specs)
                                 &body options)
  #!+sb-doc
  "DEFINE-CONDITION Name (Parent-Type*) (Slot-Spec*) Option*
   Define NAME as a condition type. This new type inherits slots and its
   report function from the specified PARENT-TYPEs. A slot spec is a list of:
     (slot-name :reader <rname> :initarg <iname> {Option Value}*

   The DEFINE-CLASS slot options :ALLOCATION, :INITFORM, [slot] :DOCUMENTATION
   and :TYPE and the overall options :DEFAULT-INITARGS and
   [type] :DOCUMENTATION are also allowed.

   The :REPORT option is peculiar to DEFINE-CONDITION. Its argument is either
   a string or a two-argument lambda or function name. If a function, the
   function is called with the condition and stream to report the condition.
   If a string, the string is printed.

   Condition types are classes, but (as allowed by ANSI and not as described in
   CLtL2) are neither STANDARD-OBJECTs nor STRUCTURE-OBJECTs. WITH-SLOTS and
   SLOT-VALUE may not be used on condition objects."
  (let* ((parent-types (or parent-types '(condition)))
         (layout (find-condition-layout name parent-types))
         (documentation nil)
         (report nil)
         (default-initargs ()))
    (collect ((slots)
              (all-readers nil append)
              (all-writers nil append))
      (dolist (spec slot-specs)
        (when (keywordp spec)
          (warn "Keyword slot name indicates probable syntax error:~%  ~S"
                spec))
        (let* ((spec (if (consp spec) spec (list spec)))
               (slot-name (first spec))
               (allocation :instance)
               (initform-p nil)
               documentation
               initform)
          (collect ((initargs)
                    (readers)
                    (writers))
            (do ((options (rest spec) (cddr options)))
                ((null options))
              (unless (and (consp options) (consp (cdr options)))
                (error "malformed condition slot spec:~%  ~S." spec))
              (let ((arg (second options)))
                (case (first options)
                  (:reader (readers arg))
                  (:writer (writers arg))
                  (:accessor
                   (readers arg)
                   (writers `(setf ,arg)))
                  (:initform
                   (when initform-p
                     (error "more than one :INITFORM in ~S" spec))
                   (setq initform-p t)
                   (setq initform arg))
                  (:initarg (initargs arg))
                  (:allocation
                   (setq allocation arg))
                  (:documentation
                   (when documentation
                     (error "more than one :DOCUMENTATION in ~S" spec))
                   (unless (stringp arg)
                     (error "slot :DOCUMENTATION argument is not a string: ~S"
                            arg))
                   (setq documentation arg))
                  (:type)
                  (t
                   (error "unknown slot option:~%  ~S" (first options))))))

            (all-readers (readers))
            (all-writers (writers))
            (slots `(make-condition-slot
                     :name ',slot-name
                     :initargs ',(initargs)
                     :readers ',(readers)
                     :writers ',(writers)
                     :initform-p ',initform-p
                     :documentation ',documentation
                     :initform
                     ,(if (sb!xc:constantp initform)
                          `',(constant-form-value initform)
                          `#'(lambda () ,initform)))))))

      (dolist (option options)
        (unless (consp option)
          (error "bad option:~%  ~S" option))
        (case (first option)
          (:documentation (setq documentation (second option)))
          (:report
           (let ((arg (second option)))
             (setq report
                   (if (stringp arg)
                       `#'(lambda (condition stream)
                            (declare (ignore condition))
                            (write-string ,arg stream))
                       `#'(lambda (condition stream)
                            (funcall #',arg condition stream))))))
          (:default-initargs
           (do ((initargs (rest option) (cddr initargs)))
               ((endp initargs))
             (let ((val (second initargs)))
               (setq default-initargs
                     (list* `',(first initargs)
                            (if (sb!xc:constantp val)
                                `',(constant-form-value val)
                                `#'(lambda () ,val))
                            default-initargs)))))
          (t
           (error "unknown option: ~S" (first option)))))

      `(progn
         (eval-when (:compile-toplevel)
           (%compiler-define-condition ',name ',parent-types ',layout
                                       ',(all-readers) ',(all-writers)))
         (eval-when (:load-toplevel :execute)
           (%define-condition ',name
                              ',parent-types
                              ',layout
                              (list ,@(slots))
                              ,documentation
                              (list ,@default-initargs)
                              ',(all-readers)
                              ',(all-writers)
                              (sb!c:source-location))
  we 're under EVAL or loaded as source .
           (%set-condition-report ',name ,report)
           ',name)))))

  various CONDITIONs specified by ANSI

(define-condition serious-condition (condition) ())

(define-condition error (serious-condition) ())

(define-condition warning (condition) ())
(define-condition style-warning (warning) ())

(defun simple-condition-printer (condition stream)
  (let ((control (simple-condition-format-control condition)))
    (if control
        (apply #'format stream
               control
               (simple-condition-format-arguments condition))
        (error "No format-control for ~S" condition))))

(define-condition simple-condition ()
  ((format-control :reader simple-condition-format-control
                   :initarg :format-control
                   :initform nil
                   :type format-control)
   (format-arguments :reader simple-condition-format-arguments
                     :initarg :format-arguments
                     :initform nil
                     :type list))
  (:report simple-condition-printer))

(define-condition simple-warning (simple-condition warning) ())

(define-condition simple-error (simple-condition error) ())

(define-condition storage-condition (serious-condition) ())

(define-condition type-error (error)
  ((datum :reader type-error-datum :initarg :datum)
   (expected-type :reader type-error-expected-type :initarg :expected-type))
  (:report
   (lambda (condition stream)
     (format stream
             "~@<The value ~2I~:_~S ~I~_is not of type ~2I~_~S.~:>"
             (type-error-datum condition)
             (type-error-expected-type condition)))))

(def!method print-object ((condition type-error) stream)
  (if *print-escape*
      (flet ((maybe-string (thing)
               (ignore-errors
                 (write-to-string thing :lines 1 :readably nil :array nil :pretty t))))
        (let ((type (maybe-string (type-error-expected-type condition)))
              (datum (maybe-string (type-error-datum condition))))
          (if (and type datum)
              (print-unreadable-object (condition stream :type t)
                (format stream "~@<expected-type: ~A ~_datum: ~A~:@>" type datum))
              (call-next-method))))
      (call-next-method)))

  not specified by ANSI , but too useful not to have around .
(define-condition simple-style-warning (simple-condition style-warning) ())
(define-condition simple-type-error (simple-condition type-error) ())

(declaim (ftype (sfunction (t t t &rest t) nil) bad-type))
(defun bad-type (datum type control &rest arguments)
  (error 'simple-type-error
         :datum datum
         :expected-type type
         :format-control control
         :format-arguments arguments))

(define-condition program-error (error) ())
(define-condition parse-error   (error) ())
(define-condition control-error (error) ())
(define-condition stream-error  (error)
  ((stream :reader stream-error-stream :initarg :stream)))

(define-condition end-of-file (stream-error) ()
  (:report
   (lambda (condition stream)
     (format stream
             "end of file on ~S"
             (stream-error-stream condition)))))

(define-condition closed-stream-error (stream-error) ()
  (:report
   (lambda (condition stream)
     (format stream "~S is closed" (stream-error-stream condition)))))

(define-condition file-error (error)
  ((pathname :reader file-error-pathname :initarg :pathname))
  (:report
   (lambda (condition stream)
     (format stream "error on file ~S" (file-error-pathname condition)))))

(define-condition package-error (error)
  ((package :reader package-error-package :initarg :package)))

(define-condition cell-error (error)
  ((name :reader cell-error-name :initarg :name)))

(def!method print-object ((condition cell-error) stream)
  (if (and *print-escape* (slot-boundp condition 'name))
      (print-unreadable-object (condition stream :type t :identity t)
        (princ (cell-error-name condition) stream))
      (call-next-method)))

(define-condition unbound-variable (cell-error) ()
  (:report
   (lambda (condition stream)
     (format stream
             "The variable ~S is unbound."
             (cell-error-name condition)))))

(define-condition undefined-function (cell-error) ()
  (:report
   (lambda (condition stream)
     (format stream
             "The function ~/sb-impl::print-symbol-with-prefix/ is undefined."
             (cell-error-name condition)))))

(define-condition special-form-function (undefined-function) ()
  (:report
   (lambda (condition stream)
     (format stream
             "Cannot FUNCALL the SYMBOL-FUNCTION of special operator ~S."
             (cell-error-name condition)))))

(define-condition arithmetic-error (error)
  ((operation :reader arithmetic-error-operation
              :initarg :operation
              :initform nil)
   (operands :reader arithmetic-error-operands
             :initarg :operands))
  (:report (lambda (condition stream)
             (format stream
                     "arithmetic error ~S signalled"
                     (type-of condition))
             (when (arithmetic-error-operation condition)
               (format stream
                       "~%Operation was ~S, operands ~S."
                       (arithmetic-error-operation condition)
                       (arithmetic-error-operands condition))))))

(define-condition division-by-zero         (arithmetic-error) ())
(define-condition floating-point-overflow  (arithmetic-error) ())
(define-condition floating-point-underflow (arithmetic-error) ())
(define-condition floating-point-inexact   (arithmetic-error) ())
(define-condition floating-point-invalid-operation (arithmetic-error) ())

(define-condition print-not-readable (error)
  ((object :reader print-not-readable-object :initarg :object))
  (:report
   (lambda (condition stream)
     (let ((obj (print-not-readable-object condition))
           (*print-array* nil))
       (format stream "~S cannot be printed readably." obj)))))

(define-condition reader-error (parse-error stream-error) ()
  (:report (lambda (condition stream)
             (%report-reader-error condition stream))))

  FORMAT - ARGS ( the usual case for READER - ERRORs signalled from
  within SBCL itself )
  the letter of the ANSI spec : this is not a condition signalled by
  SIGNAL when a format - control is supplied by the function 's first
  argument . It seems to me ( WHN ) to be basically in the spirit of
  place of CL : SIMPLE - CONDITION here . )
(define-condition simple-reader-error (reader-error simple-condition)
  ()
  (:report (lambda (condition stream)
             (%report-reader-error condition stream :simple t))))

(defun %report-reader-error (condition stream &key simple position)
  (let ((error-stream (stream-error-stream condition)))
    (pprint-logical-block (stream nil)
      (if simple
          (apply #'format stream
                 (simple-condition-format-control condition)
                 (simple-condition-format-arguments condition))
          (prin1 (class-name (class-of condition)) stream))
      (format stream "~2I~@[~_~_~:{~:(~A~): ~S~:^, ~:_~}~]~_~_Stream: ~S"
              (stream-error-position-info error-stream position)
              error-stream))))

  special SBCL extension conditions

  an error apparently caused by a bug in SBCL itself
  for * all * errors in SBCL itself . E.g. type errors and array
  indexing errors can occur in functions called from SBCL code , and
  underlying problem is a bug in SBCL . But in the fairly common case
  that the signalling code does know that it 's found a bug in SBCL ,
  users to recognize it as an SBCL bug .
(define-condition bug (simple-error)
  ()
  (:report
   (lambda (condition stream)
     (format stream
             "~@<  ~? ~:@_~?~:>"
             (simple-condition-format-control condition)
             (simple-condition-format-arguments condition)
             "~@<This is probably a bug in SBCL itself. (Alternatively, ~
              SBCL might have been corrupted by bad user code, e.g. by an ~
              undefined Lisp operation like ~S, or by stray pointers from ~
              in the OS or hardware that SBCL is running on.) If it seems to ~
              be a bug in SBCL itself, the maintainers would like to know ~
              about it. Bug reports are welcome on the SBCL ~
              mailing lists, which you can find at ~
              </>.~:@>"
             '((fmakunbound 'compile))))))

(define-condition simple-storage-condition (storage-condition simple-condition)
  ())

  E.g. in  , it might be appropriate to do something like
    # -(or   )
    # + ( or   )
  possible for test code to distinguish between ( 1 ) intentionally
  unimplemented and ( 2 ) unintentionally just screwed up somehow .
  sbcl-0.7.0 , a package screwup left the definition of
(define-condition unsupported-operator (simple-error) ())

  (:  : node " ... " )
  (:  : variable * ed - functions * )
(defun print-reference (reference stream)
  (ecase (car reference)
    (:amop
     (format stream "AMOP")
     (format stream ", ")
     (destructuring-bind (type data) (cdr reference)
       (ecase type
         (:readers "Readers for ~:(~A~) Metaobjects"
                   (substitute #\  #\- (symbol-name data)))
         (:initialization
          (format stream "Initialization of ~:(~A~) Metaobjects"
                  (substitute #\  #\- (symbol-name data))))
         (:generic-function (format stream "Generic Function ~S" data))
         (:function (format stream "Function ~S" data))
         (:section (format stream "Section ~{~D~^.~}" data)))))
    (:ansi-cl
     (format stream "The ANSI Standard")
     (format stream ", ")
     (destructuring-bind (type data) (cdr reference)
       (ecase type
         (:function (format stream "Function ~S" data))
         (:special-operator (format stream "Special Operator ~S" data))
         (:macro (format stream "Macro ~S" data))
         (:section (format stream "Section ~{~D~^.~}" data))
         (:glossary (format stream "Glossary entry for ~S" data))
         (:issue (format stream "writeup for Issue ~A" data)))))
    (:sbcl
     (format stream "The SBCL Manual")
     (format stream ", ")
     (destructuring-bind (type data) (cdr reference)
       (ecase type
         (:node (format stream "Node ~S" data))
         (:variable (format stream "Variable ~S" data))
         (:function (format stream "Function ~S" data)))))
  FIXME : other documents ( e.g. CLIM , Franz documentation :-)
    ))
(define-condition reference-condition ()
  ((references :initarg :references :reader reference-condition-references)))
(defvar *print-condition-references* t)
(def!method print-object :around ((o reference-condition) s)
  (call-next-method)
  (unless (or *print-escape* *print-readably*)
    (when (and *print-condition-references*
               (reference-condition-references o))
      (format s "~&See also:~%")
      (pprint-logical-block (s nil :per-line-prefix "  ")
        (do* ((rs (reference-condition-references o) (cdr rs))
              (r (car rs) (car rs)))
             ((null rs))
          (print-reference r s)
          (unless (null (cdr rs))
            (terpri s)))))))

(define-condition simple-reference-error (reference-condition simple-error)
  ())

(define-condition simple-reference-warning (reference-condition simple-warning)
  ())

(define-condition arguments-out-of-domain-error
    (arithmetic-error reference-condition)
  ())

(define-condition duplicate-definition (reference-condition warning)
  ((name :initarg :name :reader duplicate-definition-name))
  (:report (lambda (c s)
             (format s "~@<Duplicate definition for ~S found in ~
                        one file.~@:>"
                     (duplicate-definition-name c))))
  (:default-initargs :references (list '(:ansi-cl :section (3 2 2 3)))))

(define-condition constant-modified (reference-condition warning)
  ((fun-name :initarg :fun-name :reader constant-modified-fun-name))
  (:report (lambda (c s)
             (format s "~@<Destructive function ~S called on ~
                        constant data.~@:>"
                     (constant-modified-fun-name c))))
  (:default-initargs :references (list '(:ansi-cl :special-operator quote)
                                       '(:ansi-cl :section (3 2 2 3)))))

(define-condition package-at-variance (reference-condition simple-warning)
  ()
  (:default-initargs :references (list '(:ansi-cl :macro defpackage))))

(define-condition defconstant-uneql (reference-condition error)
  ((name :initarg :name :reader defconstant-uneql-name)
   (old-value :initarg :old-value :reader defconstant-uneql-old-value)
   (new-value :initarg :new-value :reader defconstant-uneql-new-value))
  (:report
   (lambda (condition stream)
     (format stream
             "~@<The constant ~S is being redefined (from ~S to ~S)~@:>"
             (defconstant-uneql-name condition)
             (defconstant-uneql-old-value condition)
             (defconstant-uneql-new-value condition))))
  (:default-initargs :references (list '(:ansi-cl :macro defconstant)
                                       '(:sbcl :node "Idiosyncrasies"))))

(define-condition array-initial-element-mismatch
    (reference-condition simple-warning)
  ()
  (:default-initargs
      :references (list
                   '(:ansi-cl :function make-array)
                   '(:ansi-cl :function sb!xc:upgraded-array-element-type))))

(define-condition type-warning (reference-condition simple-warning)
  ()
  (:default-initargs :references (list '(:sbcl :node "Handling of Types"))))
(define-condition type-style-warning (reference-condition simple-style-warning)
  ()
  (:default-initargs :references (list '(:sbcl :node "Handling of Types"))))

(define-condition local-argument-mismatch (reference-condition simple-warning)
  ()
  (:default-initargs :references (list '(:ansi-cl :section (3 2 2 3)))))

(define-condition format-args-mismatch (reference-condition)
  ()
  (:default-initargs :references (list '(:ansi-cl :section (22 3 10 2)))))

(define-condition format-too-few-args-warning
    (format-args-mismatch simple-warning)
  ())
(define-condition format-too-many-args-warning
    (format-args-mismatch simple-style-warning)
  ())

(define-condition implicit-generic-function-warning (style-warning)
  ((name :initarg :name :reader implicit-generic-function-name))
  (:report
   (lambda (condition stream)
     (let ((*package* (find-package :keyword)))
       (format stream "~@<Implicitly creating new generic function ~S.~:@>"
               (implicit-generic-function-name condition))))))

(define-condition extension-failure (reference-condition simple-error)
  ())

(define-condition structure-initarg-not-keyword
    (reference-condition simple-style-warning)
  ()
  (:default-initargs :references (list '(:ansi-cl :section (2 4 8 13)))))

#!+sb-package-locks
(progn

(define-condition package-lock-violation (package-error
                                          reference-condition
                                          simple-condition)
  ((current-package :initform *package*
                    :reader package-lock-violation-in-package))
  (:report
   (lambda (condition stream)
     (let ((control (simple-condition-format-control condition))
           (error-package (package-name (package-error-package condition)))
           (current-package (package-name (package-lock-violation-in-package condition))))
       (if control
           (apply #'format stream
                  (format nil "~~@<Lock on package ~A violated when ~A while in package ~A.~~:@>"
                          error-package
                          control
                          current-package)
                  (simple-condition-format-arguments condition))
           (format stream "~@<Lock on package ~A violated while in package ~A.~:@>"
                   error-package
                   current-package)))))
  #!+sb-doc
  (:documentation
   "Subtype of CL:PACKAGE-ERROR. A subtype of this error is signalled
when a package-lock is violated."))

(define-condition package-locked-error (package-lock-violation) ()
  #!+sb-doc
  (:documentation
   "Subtype of SB-EXT:PACKAGE-LOCK-VIOLATION. An error of this type is
signalled when an operation on a package violates a package lock."))

(define-condition symbol-package-locked-error (package-lock-violation)
  ((symbol :initarg :symbol :reader package-locked-error-symbol))
  #!+sb-doc
  (:documentation
   "Subtype of SB-EXT:PACKAGE-LOCK-VIOLATION. An error of this type is
signalled when an operation on a symbol violates a package lock. The
symbol that caused the violation is accessed by the function
SB-EXT:PACKAGE-LOCKED-ERROR-SYMBOL."))


(define-condition undefined-alien-error (cell-error) ()
  (:report
   (lambda (condition stream)
     (if (slot-boundp condition 'name)
         (format stream "Undefined alien: ~S" (cell-error-name condition))
         (format stream "Undefined alien symbol.")))))

(define-condition undefined-alien-variable-error (undefined-alien-error) ()
  (:report
   (lambda (condition stream)
     (declare (ignore condition))
     (format stream "Attempt to access an undefined alien variable."))))

(define-condition undefined-alien-function-error (undefined-alien-error) ()
  (:report
   (lambda (condition stream)
     (declare (ignore condition))
     (format stream "Attempt to call an undefined alien function."))))


  various other ( not specified by ANSI ) CONDITIONs

(define-condition encapsulated-condition (condition)
  ((condition :initarg :condition :reader encapsulated-condition)))

   : a condition for floating point errors when we ca n't or
  wo n't figure out what type they are . ( In FreeBSD and OpenBSD we
  signal handling and has n't been fixed as of sbcl-0.6.7 . )
(define-condition floating-point-exception (arithmetic-error)
  ((flags :initarg :traps
          :initform nil
          :reader floating-point-exception-traps))
  (:report (lambda (condition stream)
             (format stream
                     "An arithmetic error ~S was signalled.~%"
                     (type-of condition))
             (let ((traps (floating-point-exception-traps condition)))
               (if traps
                   (format stream
                           "Trapping conditions are: ~%~{ ~S~^~}~%"
                           traps)
                   (write-line
                    "No traps are enabled? How can this be?"
                    stream))))))

(define-condition invalid-array-index-error (type-error)
  ((array :initarg :array :reader invalid-array-index-error-array)
   (axis :initarg :axis :reader invalid-array-index-error-axis))
  (:report
   (lambda (condition stream)
     (let ((array (invalid-array-index-error-array condition)))
       (format stream "Index ~W out of bounds for ~@[axis ~W of ~]~S, ~
                       should be nonnegative and <~W."
               (type-error-datum condition)
               (when (> (array-rank array) 1)
                 (invalid-array-index-error-axis condition))
               (type-of array)
  Extract the bound from ( INTEGER 0 ( BOUND ) )
               (caaddr (type-error-expected-type condition)))))))

(define-condition invalid-array-error (reference-condition type-error) ()
  (:report
   (lambda (condition stream)
     (let ((*print-array* nil))
       (format stream
               "~@<Displaced array originally of type ~S has been invalidated ~
                due its displaced-to array ~S having become too small to hold ~
                it: the displaced array's dimensions have all been set to zero ~
                to trap accesses to it.~:@>"
               (type-error-expected-type condition)
               (array-displacement (type-error-datum condition))))))
  (:default-initargs
      :references
      (list '(:ansi-cl :function adjust-array))))

(define-condition index-too-large-error (type-error)
  ()
  (:report
   (lambda (condition stream)
     (format stream
             "The index ~S is too large."
             (type-error-datum condition)))))

(define-condition bounding-indices-bad-error (reference-condition type-error)
  ((object :reader bounding-indices-bad-object :initarg :object))
  (:report
   (lambda (condition stream)
     (let* ((datum (type-error-datum condition))
            (start (car datum))
            (end (cdr datum))
            (object (bounding-indices-bad-object condition)))
       (etypecase object
         (sequence
          (format stream
                  "The bounding indices ~S and ~S are bad ~
                   for a sequence of length ~S."
                  start end (length object)))
         (array
          (format stream
                  "The START and END parameters ~S and ~S are ~
                   bad for an array of total size ~S."
                  start end (array-total-size object)))))))
  (:default-initargs
      :references
      (list '(:ansi-cl :glossary "bounding index designator")
            '(:ansi-cl :issue "SUBSEQ-OUT-OF-BOUNDS:IS-AN-ERROR"))))

(define-condition nil-array-accessed-error (reference-condition type-error)
  ()
  (:report (lambda (condition stream)
             (declare (ignore condition))
             (format stream
                     "An attempt to access an array of element-type ~
                      NIL was made.  Congratulations!")))
  (:default-initargs
      :references (list '(:ansi-cl :function sb!xc:upgraded-array-element-type)
                        '(:ansi-cl :section (15 1 2 1))
                        '(:ansi-cl :section (15 1 2 2)))))

(define-condition namestring-parse-error (parse-error)
  ((complaint :reader namestring-parse-error-complaint :initarg :complaint)
   (args :reader namestring-parse-error-args :initarg :args :initform nil)
   (namestring :reader namestring-parse-error-namestring :initarg :namestring)
   (offset :reader namestring-parse-error-offset :initarg :offset))
  (:report
   (lambda (condition stream)
     (format stream
             "parse error in namestring: ~?~%  ~A~%  ~V@T^"
             (namestring-parse-error-complaint condition)
             (namestring-parse-error-args condition)
             (namestring-parse-error-namestring condition)
             (namestring-parse-error-offset condition)))))

(define-condition simple-package-error (simple-condition package-error) ())

(define-condition simple-reader-package-error (simple-reader-error package-error) ())

(define-condition reader-eof-error (end-of-file)
  ((context :reader reader-eof-error-context :initarg :context))
  (:report
   (lambda (condition stream)
     (format stream
             "unexpected end of file on ~S ~A"
             (stream-error-stream condition)
             (reader-eof-error-context condition)))))

(define-condition reader-impossible-number-error (simple-reader-error)
  ((error :reader reader-impossible-number-error-error :initarg :error))
  (:report
   (lambda (condition stream)
     (let ((error-stream (stream-error-stream condition)))
       (format stream
               "READER-ERROR ~@[at ~W ~]on ~S:~%~?~%Original error: ~A"
               (file-position-or-nil-for-error error-stream) error-stream
               (simple-condition-format-control condition)
               (simple-condition-format-arguments condition)
               (reader-impossible-number-error-error condition))))))

(define-condition standard-readtable-modified-error (reference-condition error)
  ((operation :initarg :operation :reader standard-readtable-modified-operation))
  (:report (lambda (condition stream)
             (format stream "~S would modify the standard readtable."
                     (standard-readtable-modified-operation condition))))
  (:default-initargs :references `((:ansi-cl :section (2 1 1 2))
                                   (:ansi-cl :glossary "standard readtable"))))

(define-condition standard-pprint-dispatch-table-modified-error
    (reference-condition error)
  ((operation :initarg :operation
              :reader standard-pprint-dispatch-table-modified-operation))
  (:report (lambda (condition stream)
             (format stream "~S would modify the standard pprint dispatch table."
                     (standard-pprint-dispatch-table-modified-operation
                      condition))))
  (:default-initargs
      :references `((:ansi-cl :glossary "standard pprint dispatch table"))))

(define-condition timeout (serious-condition)
  ((seconds :initarg :seconds :initform nil :reader timeout-seconds))
  (:report (lambda (condition stream)
             (format stream "Timeout occurred~@[ after ~A seconds~]."
                     (timeout-seconds condition)))))

(define-condition io-timeout (stream-error timeout)
  ((direction :reader io-timeout-direction :initarg :direction))
  (:report
   (lambda (condition stream)
     (declare (type stream stream))
     (format stream
             "I/O timeout while doing ~(~A~) on ~S."
             (io-timeout-direction condition)
             (stream-error-stream condition)))))

(define-condition deadline-timeout (timeout) ()
  (:report (lambda (condition stream)
             (format stream "A deadline was reached after ~A seconds."
                     (timeout-seconds condition)))))

(define-condition declaration-type-conflict-error (reference-condition
                                                   simple-error)
  ()
  (:default-initargs
      :format-control "symbol ~S cannot be both the name of a type and the name of a declaration"
    :references (list '(:ansi-cl :section (3 8 21)))))


(define-condition step-condition ()
  ((form :initarg :form :reader step-condition-form))

  #!+sb-doc
  (:documentation "Common base class of single-stepping conditions.
STEP-CONDITION-FORM holds a string representation of the form being
stepped."))

#!+sb-doc
(setf (fdocumentation 'step-condition-form 'function)
      "Form associated with the STEP-CONDITION.")

(define-condition step-form-condition (step-condition)
  ((args :initarg :args :reader step-condition-args))
  (:report
   (lambda (condition stream)
     (let ((*print-circle* t)
           (*print-pretty* t)
           (*print-readably* nil))
       (format stream
               (list (step-condition-form condition))
               (eq (step-condition-args condition) :unknown)
               (step-condition-args condition)))))
  #!+sb-doc
  (:documentation "Condition signalled by code compiled with
single-stepping information when about to execute a form.
STEP-CONDITION-FORM holds the form, STEP-CONDITION-PATHNAME holds the
pathname of the original file or NIL, and STEP-CONDITION-SOURCE-PATH
holds the source-path to the original form within that file or NIL.
Associated with this condition are always the restarts STEP-INTO,
STEP-NEXT, and STEP-CONTINUE."))

(define-condition step-result-condition (step-condition)
  ((result :initarg :result :reader step-condition-result)))

#!+sb-doc
(setf (fdocumentation 'step-condition-result 'function)
      "Return values associated with STEP-VALUES-CONDITION as a list,
or the variable value associated with STEP-VARIABLE-CONDITION.")

(define-condition step-values-condition (step-result-condition)
  ()
  #!+sb-doc
  (:documentation "Condition signalled by code compiled with
single-stepping information after executing a form.
STEP-CONDITION-FORM holds the form, and STEP-CONDITION-RESULT holds
the values returned by the form as a list. No associated restarts."))

(define-condition step-finished-condition (step-condition)
  ()
  (:report
   (lambda (condition stream)
     (declare (ignore condition))
     (format stream "Returning from STEP")))
  #!+sb-doc
  (:documentation "Condition signaled when STEP returns."))

(defvar *muffled-warnings* 'uninteresting-redefinition
  "A type that ought to specify a subtype of WARNING.  Whenever a
warning is signaled, if the warning if of this type and is not
handled by any other handler, it will be muffled.")

  redefinitions , but other redefinitions could be done later
(define-condition redefinition-warning (style-warning)
  ((name
    :initarg :name
    :reader redefinition-warning-name)
   (new-location
    :initarg :new-location
    :reader redefinition-warning-new-location)))

(define-condition function-redefinition-warning (redefinition-warning)
  ((new-function
    :initarg :new-function
    :reader function-redefinition-warning-new-function)))

(define-condition redefinition-with-defun (function-redefinition-warning)
  ()
  (:report (lambda (warning stream)
             (format stream "redefining ~/sb-impl::print-symbol-with-prefix/ ~
                             in DEFUN"
                     (redefinition-warning-name warning)))))

(define-condition redefinition-with-defmacro (function-redefinition-warning)
  ()
  (:report (lambda (warning stream)
             (format stream "redefining ~/sb-impl::print-symbol-with-prefix/ ~
                             in DEFMACRO"
                     (redefinition-warning-name warning)))))

(define-condition redefinition-with-defgeneric (redefinition-warning)
  ()
  (:report (lambda (warning stream)
             (format stream "redefining ~/sb-impl::print-symbol-with-prefix/ ~
                             in DEFGENERIC"
                     (redefinition-warning-name warning)))))

(define-condition redefinition-with-defmethod (redefinition-warning)
  ((qualifiers :initarg :qualifiers
               :reader redefinition-with-defmethod-qualifiers)
   (specializers :initarg :specializers
                 :reader redefinition-with-defmethod-specializers)
   (new-location :initarg :new-location
                 :reader redefinition-with-defmethod-new-location)
   (old-method :initarg :old-method
               :reader redefinition-with-defmethod-old-method))
  (:report (lambda (warning stream)
             (format stream "redefining ~S~{ ~S~} ~S in DEFMETHOD"
                     (redefinition-warning-name warning)
                     (redefinition-with-defmethod-qualifiers warning)
                     (redefinition-with-defmethod-specializers warning)))))

  Deciding which redefinitions are " interesting " .

(defun function-file-namestring (function)
  #!+sb-eval
  (when (typep function 'sb!eval:interpreted-function)
    (return-from function-file-namestring
      (sb!c:definition-source-location-namestring
          (sb!eval:interpreted-function-source-location function))))
  (let* ((fun (sb!kernel:%fun-fun function))
         (code (sb!kernel:fun-code-header fun))
         (debug-info (sb!kernel:%code-debug-info code))
         (debug-source (when debug-info
                         (sb!c::debug-info-source debug-info)))
         (namestring (when debug-source
                       (sb!c::debug-source-namestring debug-source))))
    namestring))

(defun interesting-function-redefinition-warning-p (warning old)
  (let ((new (function-redefinition-warning-new-function warning))
        (source-location (redefinition-warning-new-location warning)))
    (or
  Compiled->Interpreted is interesting .
     (and (typep old 'compiled-function)
          (typep new '(not compiled-function)))
     (and (typep old 'funcallable-instance)
          (typep new '(not funcallable-instance)))
     (let* ((old-namestring (function-file-namestring old))
            (new-namestring
             (or (function-file-namestring new)
                 (when source-location
                   (sb!c::definition-source-location-namestring source-location)))))
       (and (or (not old-namestring)
                (not new-namestring)
                (not (string= old-namestring new-namestring))))))))

(defun uninteresting-ordinary-function-redefinition-p (warning)
  (and
  There 's garbage in various places when the first DEFUN runs in
   sb!kernel::*cold-init-complete-p*
   (typep warning 'redefinition-with-defun)
   (let ((name (redefinition-warning-name warning)))
     (not (interesting-function-redefinition-warning-p
           warning (or (fdefinition name) (macro-function name)))))))

(defun uninteresting-macro-redefinition-p (warning)
  (and
   (typep warning 'redefinition-with-defmacro)
   (let ((name (redefinition-warning-name warning)))
     (not (interesting-function-redefinition-warning-p
           warning (or (macro-function name) (fdefinition name)))))))

(defun uninteresting-generic-function-redefinition-p (warning)
  (and
   (typep warning 'redefinition-with-defgeneric)
  Ca n't use the shared logic above , since GF 's do n't get a " new "
  definition -- rather the FIN - FUNCTION is set .
   (let* ((name (redefinition-warning-name warning))
          (old (fdefinition name))
          (old-location (when (typep old 'generic-function)
                          (sb!pcl::definition-source old)))
          (old-namestring (when old-location
                            (sb!c:definition-source-location-namestring old-location)))
          (new-location (redefinition-warning-new-location warning))
          (new-namestring (when new-location
                           (sb!c:definition-source-location-namestring new-location))))
     (and old-namestring
          new-namestring
          (string= old-namestring new-namestring)))))

(defun uninteresting-method-redefinition-p (warning)
  (and
   (typep warning 'redefinition-with-defmethod)
  Ca n't use the shared logic above , since GF 's do n't get a " new "
  definition -- rather the FIN - FUNCTION is set .
   (let* ((old-method (redefinition-with-defmethod-old-method warning))
          (old-location (sb!pcl::definition-source old-method))
          (old-namestring (when old-location
                            (sb!c:definition-source-location-namestring old-location)))
          (new-location (redefinition-warning-new-location warning))
          (new-namestring (when new-location
                            (sb!c:definition-source-location-namestring new-location))))
         (and new-namestring
              old-namestring
              (string= new-namestring old-namestring)))))

(deftype uninteresting-redefinition ()
  '(or (satisfies uninteresting-ordinary-function-redefinition-p)
       (satisfies uninteresting-macro-redefinition-p)
       (satisfies uninteresting-generic-function-redefinition-p)
       (satisfies uninteresting-method-redefinition-p)))

(define-condition redefinition-with-deftransform (redefinition-warning)
  ((transform :initarg :transform
              :reader redefinition-with-deftransform-transform))
  (:report (lambda (warning stream)
             (format stream "Overwriting ~S"
                     (redefinition-with-deftransform-transform warning)))))

(define-condition dubious-asterisks-around-variable-name
    (style-warning simple-condition)
  ()
  (:report (lambda (warning stream)
             (format stream "~@?, even though the name follows~@
the usual naming convention (names like *FOO*) for special variables"
                     (simple-condition-format-control warning)
                     (simple-condition-format-arguments warning)))))

(define-condition asterisks-around-lexical-variable-name
    (dubious-asterisks-around-variable-name)
  ())

(define-condition asterisks-around-constant-variable-name
    (dubious-asterisks-around-variable-name)
  ())

  We call this UNDEFINED - ALIEN - STYLE - WARNING because there are some
(define-condition undefined-alien-style-warning (style-warning)
  ((symbol :initarg :symbol :reader undefined-alien-symbol))
  (:report (lambda (warning stream)
             (format stream "Undefined alien: ~S"
                     (undefined-alien-symbol warning)))))

#!+sb-eval
(define-condition lexical-environment-too-complex (style-warning)
  ((form :initarg :form :reader lexical-environment-too-complex-form)
   (lexenv :initarg :lexenv :reader lexical-environment-too-complex-lexenv))
  (:report (lambda (warning stream)
             (format stream
                     "~@<Native lexical environment too complex for ~
                         SB-EVAL to evaluate ~S, falling back to ~
                         SIMPLE-EVAL-IN-LEXENV.  Lexenv: ~S~:@>"
                     (lexical-environment-too-complex-form warning)
                     (lexical-environment-too-complex-lexenv warning)))))

(define-condition character-decoding-error-in-comment (style-warning)
  ((stream :initarg :stream :reader decoding-error-in-comment-stream)
   (position :initarg :position :reader decoding-error-in-comment-position))
  (:report (lambda (warning stream)
             (format stream
                      "Character decoding error in a ~A-comment at ~
                      position ~A reading source stream ~A, ~
                      resyncing."
                      (decoding-error-in-comment-macro warning)
                      (decoding-error-in-comment-position warning)
                      (decoding-error-in-comment-stream warning)))))

(define-condition character-decoding-error-in-macro-char-comment
    (character-decoding-error-in-comment)
         :reader character-decoding-error-in-macro-char-comment-char)))

(define-condition character-decoding-error-in-dispatch-macro-char-comment
    (character-decoding-error-in-comment)
  was used , so if a user wants to signal one of these from a custom
  ((disp-char :initform #\# :initarg :disp-char
              :reader character-decoding-error-in-macro-char-comment-disp-char)
   (sub-char :initarg :sub-char
             :reader character-decoding-error-in-macro-char-comment-sub-char)))

(defun decoding-error-in-comment-macro (warning)
  (etypecase warning
    (character-decoding-error-in-macro-char-comment
     (character-decoding-error-in-macro-char-comment-char warning))
    (character-decoding-error-in-dispatch-macro-char-comment
     (format
      nil "~C~C"
      (character-decoding-error-in-macro-char-comment-disp-char warning)
      (character-decoding-error-in-macro-char-comment-sub-char warning)))))

(define-condition deprecated-eval-when-situations (style-warning)
  ((situations :initarg :situations
               :reader deprecated-eval-when-situations-situations))
  (:report (lambda (warning stream)
             (format stream "using deprecated EVAL-WHEN situation names~{ ~S~}"
                     (deprecated-eval-when-situations-situations warning)))))

(define-condition proclamation-mismatch (style-warning)
  ((name :initarg :name :reader proclamation-mismatch-name)
   (old :initarg :old :reader proclamation-mismatch-old)
   (new :initarg :new :reader proclamation-mismatch-new)))

(define-condition type-proclamation-mismatch (proclamation-mismatch)
  ()
  (:report (lambda (warning stream)
             (format stream
                     "The new TYPE proclamation~% ~S for ~S does not ~
                     match the old TYPE proclamation ~S"
                     (proclamation-mismatch-new warning)
                     (proclamation-mismatch-name warning)
                     (proclamation-mismatch-old warning)))))

(define-condition ftype-proclamation-mismatch (proclamation-mismatch)
  ()
  (:report (lambda (warning stream)
             (format stream
                     "The new FTYPE proclamation~% ~S for ~S does not ~
                     match the old FTYPE proclamation ~S"
                     (proclamation-mismatch-new warning)
                     (proclamation-mismatch-name warning)
                     (proclamation-mismatch-old warning)))))


(define-condition deprecation-condition ()
  ((name :initarg :name :reader deprecated-name)
   (replacements :initarg :replacements :reader deprecated-name-replacements)
   (since :initarg :since :reader deprecated-since)
   (runtime-error :initarg :runtime-error :reader deprecated-name-runtime-error)))

(def!method print-object ((condition deprecation-condition) stream)
  (let ((*package* (find-package :keyword)))
    (if *print-escape*
        (print-unreadable-object (condition stream :type t)
          (apply #'format
                 stream "~S is deprecated.~
                  (deprecated-name condition)
                  (deprecated-name-replacements condition)))
        (apply #'format
               stream "~@<~S has been deprecated as of SBCL ~A.~
                (deprecated-name condition)
                (deprecated-since condition)
                (deprecated-name-replacements condition)))))

(define-condition early-deprecation-warning (style-warning deprecation-condition)
  ())

(def!method print-object :after ((warning early-deprecation-warning) stream)
  (unless *print-escape*
    (let ((*package* (find-package :keyword)))
      (format stream "~%~@<~:@_In future SBCL versions ~S will signal a full warning ~
                      at compile-time.~:@>"
              (deprecated-name warning)))))

(define-condition late-deprecation-warning (warning deprecation-condition)
  ())

(def!method print-object :after ((warning late-deprecation-warning) stream)
  (unless *print-escape*
    (when (deprecated-name-runtime-error warning)
      (let ((*package* (find-package :keyword)))
        (format stream "~%~@<~:@_In future SBCL versions ~S will signal a runtime error.~:@>"
                (deprecated-name warning))))))

(define-condition final-deprecation-warning (warning deprecation-condition)
  ())

(def!method print-object :after ((warning final-deprecation-warning) stream)
  (unless *print-escape*
    (when (deprecated-name-runtime-error warning)
      (let ((*package* (find-package :keyword)))
        (format stream "~%~@<~:@_An error will be signaled at runtime for ~S.~:@>"
                (deprecated-name warning))))))

(define-condition deprecation-error (error deprecation-condition)
  ())


(define-condition abort-failure (control-error) ()
  (:report
   "An ABORT restart was found that failed to transfer control dynamically."))

(defun abort (&optional condition)
  #!+sb-doc
  "Transfer control to a restart named ABORT, signalling a CONTROL-ERROR if
   none exists."
  (invoke-restart (find-restart-or-control-error 'abort condition))
  ABORT signals an error in case there was a restart named 
  RESTART - BIND .
  (error 'abort-failure))

(defun muffle-warning (&optional condition)
  #!+sb-doc
  "Transfer control to a restart named MUFFLE-WARNING, signalling a
   CONTROL-ERROR if none exists."
  (invoke-restart (find-restart-or-control-error 'muffle-warning condition)))

(defun try-restart (name condition &rest arguments)
  (let ((restart (find-restart name condition)))
    (when restart
      (apply #'invoke-restart restart arguments))))

(macrolet ((define-nil-returning-restart (name args doc)
             #!-sb-doc (declare (ignore doc))
             `(defun ,name (,@args &optional condition)
                #!+sb-doc ,doc
                (try-restart ',name condition ,@args))))
  (define-nil-returning-restart continue ()
    "Transfer control to a restart named CONTINUE, or return NIL if none exists.")
  (define-nil-returning-restart store-value (value)
    "Transfer control and VALUE to a restart named STORE-VALUE, or
return NIL if none exists.")
  (define-nil-returning-restart use-value (value)
    "Transfer control and VALUE to a restart named USE-VALUE, or
return NIL if none exists.")
  (define-nil-returning-restart print-unreadably ()
    "Transfer control to a restart named SB-EXT:PRINT-UNREADABLY, or
return NIL if none exists."))


(macrolet ((def (name doc)
               #!-sb-doc (declare (ignore doc))
               `(defun ,name (condition)
                 #!+sb-doc ,doc
                 (invoke-restart (find-restart-or-control-error ',name condition)))))
  (def step-continue
      "Transfers control to the STEP-CONTINUE restart associated with
the condition, continuing execution without stepping. Signals a
CONTROL-ERROR if the restart does not exist.")
  (def step-next
      "Transfers control to the STEP-NEXT restart associated with the
condition, executing the current form without stepping and continuing
stepping with the next form. Signals CONTROL-ERROR is the restart does
not exists.")
  (def step-into
      "Transfers control to the STEP-INTO restart associated with the
condition, stepping into the current form. Signals a CONTROL-ERROR is
the restart does not exist."))

  Compiler macro magic

(define-condition compiler-macro-keyword-problem ()
  ((argument :initarg :argument :reader compiler-macro-keyword-argument))
  (:report (lambda (condition stream)
             (format stream "~@<Argument ~S in keyword position is not ~
                             a self-evaluating symbol, preventing compiler-macro ~
                             expansion.~@:>"
                     (compiler-macro-keyword-argument condition)))))

(/show0 "condition.lisp end of file")
