src/pcl/describe.lisp

   1 ;;;; that part of the DESCRIBE mechanism which is based on code from
   2 ;;;; PCL
   3
   4 ;;;; This software is part of the SBCL system. See the README file for
   5 ;;;; more information.
   6
   7 ;;;; This software is derived from software originally released by Xerox
   8 ;;;; Corporation. Copyright and release statements follow. Later modifications
   9 ;;;; to the software are in the public domain and are provided with
  10 ;;;; absolutely no warranty. See the COPYING and CREDITS files for more
  11 ;;;; information.
  12
  13 ;;;; copyright information from original PCL sources:
  14 ;;;;
  15 ;;;; Copyright (c) 1985, 1986, 1987, 1988, 1989, 1990 Xerox Corporation.
  16 ;;;; All rights reserved.
  17 ;;;;
  18 ;;;; Use and copying of this software and preparation of derivative works based
  19 ;;;; upon this software are permitted. Any distribution of this software or
  20 ;;;; derivative works must comply with all applicable United States export
  21 ;;;; control laws.
  22 ;;;;
  23 ;;;; This software is made available AS IS, and Xerox Corporation makes no
  24 ;;;; warranty about the software, its performance or its conformity to any
  25 ;;;; specification.
  26
  27 (in-package "SB-PCL")
  28
  29 (defmethod slots-to-inspect ((class slot-class) (object slot-object))
  30   (class-slots class))
  31
  32 (defmethod describe-object ((object slot-object) stream)
  33
  34   (fresh-line stream)
  35
  36   (let* ((class (class-of object))
  37          (slotds (slots-to-inspect class object))
  38          (max-slot-name-length 0)
  39          (instance-slotds ())
  40          (class-slotds ())
  41          (other-slotds ()))
  42
  43     (format stream "~&~@<~S ~_is an instance of class ~S.~:>" object class)
  44
  45     ;; Figure out a good width for the slot-name column.
  46     (flet ((adjust-slot-name-length (name)
  47              (setq max-slot-name-length
  48                    (max max-slot-name-length
  49                         (length (the string (symbol-name name)))))))
  50       (dolist (slotd slotds)
  51         (adjust-slot-name-length (slot-definition-name slotd))
  52         (case (slot-definition-allocation slotd)
  53           (:instance (push slotd instance-slotds))
  54           (:class  (push slotd class-slotds))
  55           (otherwise (push slotd other-slotds))))
  56       (setq max-slot-name-length  (min (+ max-slot-name-length 3) 30)))
  57
  58     ;; Now that we know the width, we can print.
  59     (flet ((describe-slot (name value &optional (allocation () alloc-p))
  60              (if alloc-p
  61                  (format stream
  62                          "~& ~A ~S ~VT  ~S"
  63                          name allocation (+ max-slot-name-length 7) value)
  64                  (format stream
  65                          "~& ~A~VT  ~S"
  66                          name max-slot-name-length value))))
  67       (when instance-slotds
  68         (format stream "~&The following slots have :INSTANCE allocation:")
  69         (dolist (slotd (nreverse instance-slotds))
  70           (describe-slot
  71            (slot-definition-name slotd)
  72            (slot-value-or-default object
  73                                   (slot-definition-name slotd)))))
  74       (when class-slotds
  75         (format stream "~&The following slots have :CLASS allocation:")
  76         (dolist (slotd (nreverse class-slotds))
  77           (describe-slot
  78            (slot-definition-name slotd)
  79            (slot-value-or-default object
  80                                   (slot-definition-name slotd)))))
  81       (when other-slotds
  82         (format stream "~&The following slots have allocation as shown:")
  83         (dolist (slotd (nreverse other-slotds))
  84           (describe-slot
  85            (slot-definition-name slotd)
  86            (slot-value-or-default object
  87                                   (slot-definition-name slotd))
  88            (slot-definition-allocation slotd))))))
  89
  90   (terpri stream))
  91
  92 (defmethod describe-object ((fun standard-generic-function) stream)
  93   (format stream "~&~A is a generic function." fun)
  94   (when (documentation fun t)
  95     (format stream "~&Its documentation is: ~A" (documentation fun t)))
  96   (format stream "~&Its lambda-list is:~&  ~S"
  97           (generic-function-pretty-arglist fun))
  98   (format stream "~&Its method-combination is:~&  ~S"
  99           (generic-function-method-combination fun))
 100   (let ((methods (generic-function-methods fun)))
 101     (if (null methods)
 102         (format stream "~&It has no methods.~%")
 103         (let ((gf-name (generic-function-name fun)))
 104           (format stream "~&Its methods are:")
 105           (dolist (method methods)
 106             (format stream "~&  (~A ~{~S ~}~:S)~%"
 107                     gf-name
 108                     (method-qualifiers method)
 109                     (unparse-specializers fun (method-specializers method)))
 110             (when (documentation method t)
 111               (format stream "~&    Method documentation: ~A"
 112                       (documentation method t))))))))
 113
 114 (defmethod describe-object ((class class) stream)
 115   (flet ((pretty-class (c) (or (class-name c) c)))
 116     (macrolet ((ft (string &rest args) `(format stream ,string ,@args)))
 117       (ft "~&~@<~S is a class. It is an instance of ~S.~:@>"
 118           class (pretty-class (class-of class)))
 119       (let ((name (class-name class)))
 120         (if name
 121             (if (eq class (find-class name nil))
 122                 (ft "~&~@<Its proper name is ~S.~@:>" name)
 123                 (ft "~&~@<Its name is ~S, but this is not a proper name.~@:>"
 124                     name))
 125             (ft "~&~@<It has no name (the name is NIL).~@:>")))
 126       (ft "~&~@<The direct superclasses are: ~:S, and the direct ~
 127            subclasses are: ~:S.~I~_The class is ~:[not ~;~]finalized~
 128            ~:[. ~;; its class precedence list is:~2I~_~:*~S.~]~I~_~
 129            There ~[are~;is~:;are~] ~:*~S method~:P specialized for ~
 130            this class.~:@>~%"
 131           (mapcar #'pretty-class (class-direct-superclasses class))
 132           (mapcar #'pretty-class (class-direct-subclasses class))
 133           (class-finalized-p class)
 134           (mapcar #'pretty-class (cpl-or-nil class))
 135           (length (specializer-direct-methods class))))))
 136
 137 (defmethod describe-object ((package package) stream)
 138   (format stream "~&~S is a ~S." package (type-of package))
 139   (format stream
 140           "~@[~&~@<It has nicknames ~2I~{~:_~S~^ ~}~:>~]"
 141           (package-nicknames package))
 142   (format stream
 143           "~&It has ~S internal and ~S external symbols."
 144           (package-internal-symbol-count package)
 145           (package-external-symbol-count package))
 146   (flet (;; Turn a list of packages into something a human likes
 147          ;; to read.
 148          (humanize (package-list)
 149            (sort (mapcar #'package-name package-list) #'string<)))
 150     (format stream
 151             "~@[~&~@<It uses packages named ~2I~{~:_~S~^ ~}~:>~]"
 152             (humanize (package-use-list package)))
 153     (format stream
 154             "~@[~&~@<It is used by packages named ~2I~{~:_~S~^ ~}~:>~]"
 155             (humanize (package-used-by-list package))))
 156   (terpri stream))