3 ;;;; This software is part of the SBCL system. See the README file for
6 ;;;; This software is derived from the CMU CL system, which was
7 ;;;; written at Carnegie Mellon University and released into the
8 ;;;; public domain. The software is in the public domain and is
9 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
10 ;;;; files for more information.
12 (in-package "SB!IMPL")
14 ;;;; exported printer control variables
16 ;;; FIXME: Many of these have nontrivial types, e.g. *PRINT-LEVEL*,
17 ;;; *PRINT-LENGTH*, and *PRINT-LINES* are (OR NULL UNSIGNED-BYTE).
19 (defvar *print-readably* nil
21 "If true, all objects will printed readably. If readable printing is
22 impossible, an error will be signalled. This overrides the value of
24 (defvar *print-escape* t
26 "Should we print in a reasonably machine-readable way? (possibly
27 overridden by *PRINT-READABLY*)")
28 (defvar *print-pretty* nil ; (set later when pretty-printer is initialized)
30 "Should pretty printing be used?")
31 (defvar *print-base* 10.
33 "the output base for RATIONALs (including integers)")
34 (defvar *print-radix* nil
36 "Should base be verified when printing RATIONALs?")
37 (defvar *print-level* nil
39 "How many levels should be printed before abbreviating with \"#\"?")
40 (defvar *print-length* nil
42 "How many elements at any level should be printed before abbreviating
44 (defvar *print-circle* nil
46 "Should we use #n= and #n# notation to preserve uniqueness in general (and
47 circularity in particular) when printing?")
48 (defvar *print-case* :upcase
50 "What case should the printer should use default?")
51 (defvar *print-array* t
53 "Should the contents of arrays be printed?")
54 (defvar *print-gensym* t
56 "Should #: prefixes be used when printing symbols with null SYMBOL-PACKAGE?")
57 (defvar *print-lines* nil
59 "the maximum number of lines to print per object")
60 (defvar *print-right-margin* nil
62 "the position of the right margin in ems (for pretty-printing)")
63 (defvar *print-miser-width* nil
65 "If the remaining space between the current column and the right margin
66 is less than this, then print using ``miser-style'' output. Miser
67 style conditional newlines are turned on, and all indentations are
68 turned off. If NIL, never use miser mode.")
69 (defvar *print-pprint-dispatch*)
71 (setf (fdocumentation '*print-pprint-dispatch* 'variable)
72 "the pprint-dispatch-table that controls how to pretty-print objects")
74 (defmacro with-standard-io-syntax (&body body)
76 "Bind the reader and printer control variables to values that enable READ
77 to reliably read the results of PRINT. These values are:
78 *PACKAGE* the COMMON-LISP-USER package
88 *PRINT-MISER-WIDTH* NIL
92 *PRINT-RIGHT-MARGIN* NIL
94 *READ-DEFAULT-FLOAT-FORMAT* SINGLE-FLOAT
97 *READTABLE* the standard readtable"
98 `(%with-standard-io-syntax (lambda () ,@body)))
100 (defun %with-standard-io-syntax (function)
101 (declare (type function function))
102 (let ((*package* (find-package "COMMON-LISP-USER"))
105 (*print-case* :upcase)
112 (*print-miser-width* nil)
116 (*print-right-margin* nil)
118 (*read-default-float-format* 'single-float)
120 (*read-suppress* nil)
121 ;; FIXME: It doesn't seem like a good idea to expose our
122 ;; disaster-recovery *STANDARD-READTABLE* here. What if some
123 ;; enterprising user corrupts the disaster-recovery readtable
124 ;; by doing destructive readtable operations within
125 ;; WITH-STANDARD-IO-SYNTAX? Perhaps we should do a
126 ;; COPY-READTABLE? The consing would be unfortunate, though.
127 (*readtable* *standard-readtable*))
130 ;;;; routines to print objects
132 (defun write (object &key
133 ((:stream stream) *standard-output*)
134 ((:escape *print-escape*) *print-escape*)
135 ((:radix *print-radix*) *print-radix*)
136 ((:base *print-base*) *print-base*)
137 ((:circle *print-circle*) *print-circle*)
138 ((:pretty *print-pretty*) *print-pretty*)
139 ((:level *print-level*) *print-level*)
140 ((:length *print-length*) *print-length*)
141 ((:case *print-case*) *print-case*)
142 ((:array *print-array*) *print-array*)
143 ((:gensym *print-gensym*) *print-gensym*)
144 ((:readably *print-readably*) *print-readably*)
145 ((:right-margin *print-right-margin*)
146 *print-right-margin*)
147 ((:miser-width *print-miser-width*)
149 ((:lines *print-lines*) *print-lines*)
150 ((:pprint-dispatch *print-pprint-dispatch*)
151 *print-pprint-dispatch*))
153 "Output OBJECT to the specified stream, defaulting to *STANDARD-OUTPUT*"
154 (output-object object (out-synonym-of stream))
157 (defun prin1 (object &optional stream)
159 "Output a mostly READable printed representation of OBJECT on the specified
161 (let ((*print-escape* t))
162 (output-object object (out-synonym-of stream)))
165 (defun princ (object &optional stream)
167 "Output an aesthetic but not necessarily READable printed representation
168 of OBJECT on the specified STREAM."
169 (let ((*print-escape* nil)
170 (*print-readably* nil))
171 (output-object object (out-synonym-of stream)))
174 (defun print (object &optional stream)
176 "Output a newline, the mostly READable printed representation of OBJECT, and
177 space to the specified STREAM."
178 (let ((stream (out-synonym-of stream)))
180 (prin1 object stream)
181 (write-char #\space stream)
184 (defun pprint (object &optional stream)
186 "Prettily output OBJECT preceded by a newline."
187 (let ((*print-pretty* t)
189 (stream (out-synonym-of stream)))
191 (output-object object stream))
194 (defun write-to-string
196 ((:escape *print-escape*) *print-escape*)
197 ((:radix *print-radix*) *print-radix*)
198 ((:base *print-base*) *print-base*)
199 ((:circle *print-circle*) *print-circle*)
200 ((:pretty *print-pretty*) *print-pretty*)
201 ((:level *print-level*) *print-level*)
202 ((:length *print-length*) *print-length*)
203 ((:case *print-case*) *print-case*)
204 ((:array *print-array*) *print-array*)
205 ((:gensym *print-gensym*) *print-gensym*)
206 ((:readably *print-readably*) *print-readably*)
207 ((:right-margin *print-right-margin*) *print-right-margin*)
208 ((:miser-width *print-miser-width*) *print-miser-width*)
209 ((:lines *print-lines*) *print-lines*)
210 ((:pprint-dispatch *print-pprint-dispatch*)
211 *print-pprint-dispatch*))
213 "Return the printed representation of OBJECT as a string."
214 (stringify-object object))
216 (defun prin1-to-string (object)
218 "Return the printed representation of OBJECT as a string with
220 (let ((*print-escape* t))
221 (stringify-object object)))
223 (defun princ-to-string (object)
225 "Return the printed representation of OBJECT as a string with
227 (let ((*print-escape* nil)
228 (*print-readably* nil))
229 (stringify-object object)))
231 ;;; This produces the printed representation of an object as a string.
232 ;;; The few ...-TO-STRING functions above call this.
233 (defvar *string-output-streams* ())
234 (defun stringify-object (object)
235 (let ((stream (if *string-output-streams*
236 (pop *string-output-streams*)
237 (make-string-output-stream))))
238 (setup-printer-state)
239 (output-object object stream)
241 (get-output-stream-string stream)
242 (push stream *string-output-streams*))))
244 ;;;; support for the PRINT-UNREADABLE-OBJECT macro
246 ;;; guts of PRINT-UNREADABLE-OBJECT
247 (defun %print-unreadable-object (object stream type identity body)
248 (declare (type (or null function) body))
249 (when *print-readably*
250 (error 'print-not-readable :object object))
251 (flet ((print-description ()
253 (write (type-of object) :stream stream :circle nil
254 :level nil :length nil)
255 (write-char #\space stream))
259 (when (or body (not type))
260 (write-char #\space stream))
261 (write-char #\{ stream)
262 (write (get-lisp-obj-address object) :stream stream
264 (write-char #\} stream))))
265 (cond ((print-pretty-on-stream-p stream)
266 ;; Since we're printing prettily on STREAM, format the
267 ;; object within a logical block. PPRINT-LOGICAL-BLOCK does
268 ;; not rebind the stream when it is already a pretty stream,
269 ;; so output from the body will go to the same stream.
270 (pprint-logical-block (stream nil :prefix "#<" :suffix ">")
271 (print-description)))
273 (write-string "#<" stream)
275 (write-char #\> stream))))
278 ;;;; OUTPUT-OBJECT -- the main entry point
280 ;;; Objects whose print representation identifies them EQLly don't
281 ;;; need to be checked for circularity.
282 (defun uniquely-identified-by-print-p (x)
286 (symbol-package x))))
288 ;;; Output OBJECT to STREAM observing all printer control variables.
289 (defun output-object (object stream)
290 (labels ((print-it (stream)
292 (sb!pretty:output-pretty-object object stream)
293 (output-ugly-object object stream)))
295 (multiple-value-bind (marker initiate)
296 (check-for-circularity object t)
297 (if (eq initiate :initiate)
298 (let ((*circularity-hash-table*
299 (make-hash-table :test 'eq)))
300 (check-it (make-broadcast-stream))
301 (let ((*circularity-counter* 0))
305 (when (handle-circularity marker stream)
307 (print-it stream))))))
308 (cond (;; Maybe we don't need to bother with circularity detection.
309 (or (not *print-circle*)
310 (uniquely-identified-by-print-p object))
312 (;; If we have already started circularity detection, this
313 ;; object might be a shared reference. If we have not, then
314 ;; if it is a compound object it might contain a circular
315 ;; reference to itself or multiple shared references.
316 (or *circularity-hash-table*
317 (compound-object-p object))
320 (print-it stream)))))
322 ;;; a hack to work around recurring gotchas with printing while
323 ;;; DEFGENERIC PRINT-OBJECT is being built
325 ;;; (hopefully will go away naturally when CLOS moves into cold init)
326 (defvar *print-object-is-disabled-p*)
328 ;;; Output OBJECT to STREAM observing all printer control variables
329 ;;; except for *PRINT-PRETTY*. Note: if *PRINT-PRETTY* is non-NIL,
330 ;;; then the pretty printer will be used for any components of OBJECT,
331 ;;; just not for OBJECT itself.
332 (defun output-ugly-object (object stream)
334 ;; KLUDGE: The TYPECASE approach here is non-ANSI; the ANSI definition of
335 ;; PRINT-OBJECT says it provides printing and we're supposed to provide
336 ;; PRINT-OBJECT methods covering all classes. We deviate from this
337 ;; by using PRINT-OBJECT only when we print instance values. However,
338 ;; ANSI makes it hard to tell that we're deviating from this:
339 ;; (1) ANSI specifies that the user isn't supposed to call PRINT-OBJECT
341 ;; (2) ANSI (section 11.1.2.1.2) says it's undefined to define
342 ;; a method on an external symbol in the CL package which is
343 ;; applicable to arg lists containing only direct instances of
344 ;; standardized classes.
345 ;; Thus, in order for the user to detect our sleaziness in conforming
346 ;; code, he has to do something relatively obscure like
347 ;; (1) actually use tools like FIND-METHOD to look for PRINT-OBJECT
349 ;; (2) define a PRINT-OBJECT method which is specialized on the stream
350 ;; value (e.g. a Gray stream object).
351 ;; As long as no one comes up with a non-obscure way of detecting this
352 ;; sleaziness, fixing this nonconformity will probably have a low
353 ;; priority. -- WHN 2001-11-25
356 (output-symbol object stream)
357 (output-list object stream)))
359 (cond ((not (and (boundp '*print-object-is-disabled-p*)
360 *print-object-is-disabled-p*))
361 (print-object object stream))
362 ((typep object 'structure-object)
363 (default-structure-print object stream *current-level-in-print*))
365 (write-string "#<INSTANCE but not STRUCTURE-OBJECT>" stream))))
367 (unless (and (funcallable-instance-p object)
368 (printed-as-funcallable-standard-class object stream))
369 (output-fun object stream)))
371 (output-symbol object stream))
375 (output-integer object stream))
377 (output-float object stream))
379 (output-ratio object stream))
381 (output-ratio object stream))
383 (output-complex object stream))))
385 (output-character object stream))
387 (output-vector object stream))
389 (output-array object stream))
391 (output-sap object stream))
393 (output-weak-pointer object stream))
395 (output-lra object stream))
397 (output-code-component object stream))
399 (output-fdefn object stream))
401 (output-random object stream))))
405 ;;; values of *PRINT-CASE* and (READTABLE-CASE *READTABLE*) the last
406 ;;; time the printer was called
407 (defvar *previous-case* nil)
408 (defvar *previous-readtable-case* nil)
410 ;;; This variable contains the current definition of one of three
411 ;;; symbol printers. SETUP-PRINTER-STATE sets this variable.
412 (defvar *internal-symbol-output-fun* nil)
414 ;;; This function sets the internal global symbol
415 ;;; *INTERNAL-SYMBOL-OUTPUT-FUN* to the right function depending on
416 ;;; the value of *PRINT-CASE*. See the manual for details. The print
417 ;;; buffer stream is also reset.
418 (defun setup-printer-state ()
419 (unless (and (eq *print-case* *previous-case*)
420 (eq (readtable-case *readtable*) *previous-readtable-case*))
421 (setq *previous-case* *print-case*)
422 (setq *previous-readtable-case* (readtable-case *readtable*))
423 (unless (member *print-case* '(:upcase :downcase :capitalize))
424 (setq *print-case* :upcase)
425 (error "invalid *PRINT-CASE* value: ~S" *previous-case*))
426 (unless (member *previous-readtable-case*
427 '(:upcase :downcase :invert :preserve))
428 (setf (readtable-case *readtable*) :upcase)
429 (error "invalid READTABLE-CASE value: ~S" *previous-readtable-case*))
431 (setq *internal-symbol-output-fun*
432 (case *previous-readtable-case*
435 (:upcase #'output-preserve-symbol)
436 (:downcase #'output-lowercase-symbol)
437 (:capitalize #'output-capitalize-symbol)))
440 (:upcase #'output-uppercase-symbol)
441 (:downcase #'output-preserve-symbol)
442 (:capitalize #'output-capitalize-symbol)))
443 (:preserve #'output-preserve-symbol)
444 (:invert #'output-invert-symbol)))))
446 ;;; Output PNAME (a symbol-name or package-name) surrounded with |'s,
447 ;;; and with any embedded |'s or \'s escaped.
448 (defun output-quoted-symbol-name (pname stream)
449 (write-char #\| stream)
450 (dotimes (index (length pname))
451 (let ((char (schar pname index)))
452 (when (or (char= char #\\) (char= char #\|))
453 (write-char #\\ stream))
454 (write-char char stream)))
455 (write-char #\| stream))
457 (defun output-symbol (object stream)
458 (if (or *print-escape* *print-readably*)
459 (let ((package (symbol-package object))
460 (name (symbol-name object)))
462 ;; The ANSI spec "22.1.3.3.1 Package Prefixes for Symbols"
463 ;; requires that keywords be printed with preceding colons
464 ;; always, regardless of the value of *PACKAGE*.
465 ((eq package *keyword-package*)
466 (write-char #\: stream))
467 ;; Otherwise, if the symbol's home package is the current
468 ;; one, then a prefix is never necessary.
469 ((eq package (sane-package)))
470 ;; Uninterned symbols print with a leading #:.
472 (when (or *print-gensym* *print-readably*)
473 (write-string "#:" stream)))
475 (multiple-value-bind (symbol accessible)
476 (find-symbol name (sane-package))
477 ;; If we can find the symbol by looking it up, it need not
478 ;; be qualified. This can happen if the symbol has been
479 ;; inherited from a package other than its home package.
480 (unless (and accessible (eq symbol object))
481 (output-symbol-name (package-name package) stream)
482 (multiple-value-bind (symbol externalp)
483 (find-external-symbol name package)
484 (declare (ignore symbol))
486 (write-char #\: stream)
487 (write-string "::" stream)))))))
488 (output-symbol-name name stream))
489 (output-symbol-name (symbol-name object) stream nil)))
491 ;;; Output the string NAME as if it were a symbol name. In other
492 ;;; words, diddle its case according to *PRINT-CASE* and
494 (defun output-symbol-name (name stream &optional (maybe-quote t))
495 (declare (type simple-string name))
496 (let ((*readtable* (if *print-readably* *standard-readtable* *readtable*)))
497 (setup-printer-state)
498 (if (and maybe-quote (symbol-quotep name))
499 (output-quoted-symbol-name name stream)
500 (funcall *internal-symbol-output-fun* name stream))))
502 ;;;; escaping symbols
504 ;;; When we print symbols we have to figure out if they need to be
505 ;;; printed with escape characters. This isn't a whole lot easier than
506 ;;; reading symbols in the first place.
508 ;;; For each character, the value of the corresponding element is a
509 ;;; fixnum with bits set corresponding to attributes that the
510 ;;; character has. At characters have at least one bit set, so we can
511 ;;; search for any character with a positive test.
512 (defvar *character-attributes*
513 (make-array 160 ; FIXME
514 :element-type '(unsigned-byte 16)
516 (declaim (type (simple-array (unsigned-byte 16) (#.160)) ; FIXME
517 *character-attributes*))
519 ;;; constants which are a bit-mask for each interesting character attribute
520 (defconstant other-attribute (ash 1 0)) ; Anything else legal.
521 (defconstant number-attribute (ash 1 1)) ; A numeric digit.
522 (defconstant uppercase-attribute (ash 1 2)) ; An uppercase letter.
523 (defconstant lowercase-attribute (ash 1 3)) ; A lowercase letter.
524 (defconstant sign-attribute (ash 1 4)) ; +-
525 (defconstant extension-attribute (ash 1 5)) ; ^_
526 (defconstant dot-attribute (ash 1 6)) ; .
527 (defconstant slash-attribute (ash 1 7)) ; /
528 (defconstant funny-attribute (ash 1 8)) ; Anything illegal.
530 (eval-when (:compile-toplevel :load-toplevel :execute)
532 ;;; LETTER-ATTRIBUTE is a local of SYMBOL-QUOTEP. It matches letters
533 ;;; that don't need to be escaped (according to READTABLE-CASE.)
534 (defparameter *attribute-names*
535 `((number . number-attribute) (lowercase . lowercase-attribute)
536 (uppercase . uppercase-attribute) (letter . letter-attribute)
537 (sign . sign-attribute) (extension . extension-attribute)
538 (dot . dot-attribute) (slash . slash-attribute)
539 (other . other-attribute) (funny . funny-attribute)))
543 (flet ((set-bit (char bit)
544 (let ((code (char-code char)))
545 (setf (aref *character-attributes* code)
546 (logior bit (aref *character-attributes* code))))))
548 (dolist (char '(#\! #\@ #\$ #\% #\& #\* #\= #\~ #\[ #\] #\{ #\}
550 (set-bit char other-attribute))
553 (set-bit (digit-char i) number-attribute))
555 (do ((code (char-code #\A) (1+ code))
556 (end (char-code #\Z)))
558 (declare (fixnum code end))
559 (set-bit (code-char code) uppercase-attribute)
560 (set-bit (char-downcase (code-char code)) lowercase-attribute))
562 (set-bit #\- sign-attribute)
563 (set-bit #\+ sign-attribute)
564 (set-bit #\^ extension-attribute)
565 (set-bit #\_ extension-attribute)
566 (set-bit #\. dot-attribute)
567 (set-bit #\/ slash-attribute)
569 ;; Mark anything not explicitly allowed as funny.
570 (dotimes (i 160) ; FIXME
571 (when (zerop (aref *character-attributes* i))
572 (setf (aref *character-attributes* i) funny-attribute))))
574 ;;; For each character, the value of the corresponding element is the
575 ;;; lowest base in which that character is a digit.
576 (defvar *digit-bases*
577 (make-array 128 ; FIXME
578 :element-type '(unsigned-byte 8)
579 :initial-element 36))
580 (declaim (type (simple-array (unsigned-byte 8) (#.128)) ; FIXME
583 (let ((char (digit-char i 36)))
584 (setf (aref *digit-bases* (char-code char)) i)))
586 ;;; A FSM-like thingie that determines whether a symbol is a potential
587 ;;; number or has evil characters in it.
588 (defun symbol-quotep (name)
589 (declare (simple-string name))
590 (macrolet ((advance (tag &optional (at-end t))
593 ,(if at-end '(go TEST-SIGN) '(return nil)))
594 (setq current (schar name index)
595 code (char-code current)
597 ((< code 160) (aref attributes code))
598 ((upper-case-p current) uppercase-attribute)
599 ((lower-case-p current) lowercase-attribute)
600 (t other-attribute)))
603 (test (&rest attributes)
615 `(and (< code 128) ; FIXME
616 (< (the fixnum (aref bases code)) base))))
618 (prog ((len (length name))
619 (attributes *character-attributes*)
620 (bases *digit-bases*)
623 (case (readtable-case *readtable*)
624 (:upcase uppercase-attribute)
625 (:downcase lowercase-attribute)
626 (t (logior lowercase-attribute uppercase-attribute))))
631 (declare (fixnum len base index bits code))
634 TEST-SIGN ; At end, see whether it is a sign...
635 (return (not (test sign)))
637 OTHER ; not potential number, see whether funny chars...
638 (let ((mask (logxor (logior lowercase-attribute uppercase-attribute
641 (do ((i (1- index) (1+ i)))
642 ((= i len) (return-from symbol-quotep nil))
643 (unless (zerop (logand (let* ((char (schar name i))
644 (code (char-code char)))
646 ((< code 160) (aref attributes code))
647 ((upper-case-p char) uppercase-attribute)
648 ((lower-case-p char) lowercase-attribute)
649 (t other-attribute)))
651 (return-from symbol-quotep t))))
656 (advance LAST-DIGIT-ALPHA)
658 (when (test letter number other slash) (advance OTHER nil))
659 (when (char= current #\.) (advance DOT-FOUND))
660 (when (test sign extension) (advance START-STUFF nil))
663 DOT-FOUND ; leading dots...
664 (when (test letter) (advance START-DOT-MARKER nil))
665 (when (digitp) (advance DOT-DIGIT))
666 (when (test number other) (advance OTHER nil))
667 (when (test extension slash sign) (advance START-DOT-STUFF nil))
668 (when (char= current #\.) (advance DOT-FOUND))
671 START-STUFF ; leading stuff before any dot or digit
674 (advance LAST-DIGIT-ALPHA)
676 (when (test number other) (advance OTHER nil))
677 (when (test letter) (advance START-MARKER nil))
678 (when (char= current #\.) (advance START-DOT-STUFF nil))
679 (when (test sign extension slash) (advance START-STUFF nil))
682 START-MARKER ; number marker in leading stuff...
683 (when (test letter) (advance OTHER nil))
686 START-DOT-STUFF ; leading stuff containing dot without digit...
687 (when (test letter) (advance START-DOT-STUFF nil))
688 (when (digitp) (advance DOT-DIGIT))
689 (when (test sign extension dot slash) (advance START-DOT-STUFF nil))
690 (when (test number other) (advance OTHER nil))
693 START-DOT-MARKER ; number marker in leading stuff with dot..
694 ;; leading stuff containing dot without digit followed by letter...
695 (when (test letter) (advance OTHER nil))
698 DOT-DIGIT ; in a thing with dots...
699 (when (test letter) (advance DOT-MARKER))
700 (when (digitp) (advance DOT-DIGIT))
701 (when (test number other) (advance OTHER nil))
702 (when (test sign extension dot slash) (advance DOT-DIGIT))
705 DOT-MARKER ; number marker in number with dot...
706 (when (test letter) (advance OTHER nil))
709 LAST-DIGIT-ALPHA ; previous char is a letter digit...
710 (when (or (digitp) (test sign slash))
711 (advance ALPHA-DIGIT))
712 (when (test letter number other dot) (advance OTHER nil))
715 ALPHA-DIGIT ; seen a digit which is a letter...
716 (when (or (digitp) (test sign slash))
718 (advance LAST-DIGIT-ALPHA)
719 (advance ALPHA-DIGIT)))
720 (when (test letter) (advance ALPHA-MARKER))
721 (when (test number other dot) (advance OTHER nil))
724 ALPHA-MARKER ; number marker in number with alpha digit...
725 (when (test letter) (advance OTHER nil))
728 DIGIT ; seen only ordinary (non-alphabetic) numeric digits...
731 (advance ALPHA-DIGIT)
733 (when (test number other) (advance OTHER nil))
734 (when (test letter) (advance MARKER))
735 (when (test extension slash sign) (advance DIGIT))
736 (when (char= current #\.) (advance DOT-DIGIT))
739 MARKER ; number marker in a numeric number...
740 ;; ("What," you may ask, "is a 'number marker'?" It's something
741 ;; that a conforming implementation might use in number syntax.
742 ;; See ANSI 2.3.1.1 "Potential Numbers as Tokens".)
743 (when (test letter) (advance OTHER nil))
746 ;;;; *INTERNAL-SYMBOL-OUTPUT-FUN*
748 ;;;; case hackery: These functions are stored in
749 ;;;; *INTERNAL-SYMBOL-OUTPUT-FUN* according to the values of
750 ;;;; *PRINT-CASE* and READTABLE-CASE.
753 ;;; READTABLE-CASE *PRINT-CASE*
755 ;;; :DOWNCASE :DOWNCASE
757 (defun output-preserve-symbol (pname stream)
758 (declare (simple-string pname))
759 (write-string pname stream))
762 ;;; READTABLE-CASE *PRINT-CASE*
763 ;;; :UPCASE :DOWNCASE
764 (defun output-lowercase-symbol (pname stream)
765 (declare (simple-string pname))
766 (dotimes (index (length pname))
767 (let ((char (schar pname index)))
768 (write-char (char-downcase char) stream))))
771 ;;; READTABLE-CASE *PRINT-CASE*
772 ;;; :DOWNCASE :UPCASE
773 (defun output-uppercase-symbol (pname stream)
774 (declare (simple-string pname))
775 (dotimes (index (length pname))
776 (let ((char (schar pname index)))
777 (write-char (char-upcase char) stream))))
780 ;;; READTABLE-CASE *PRINT-CASE*
781 ;;; :UPCASE :CAPITALIZE
782 ;;; :DOWNCASE :CAPITALIZE
783 (defun output-capitalize-symbol (pname stream)
784 (declare (simple-string pname))
785 (let ((prev-not-alphanum t)
786 (up (eq (readtable-case *readtable*) :upcase)))
787 (dotimes (i (length pname))
788 (let ((char (char pname i)))
790 (if (or prev-not-alphanum (lower-case-p char))
792 (char-downcase char))
793 (if prev-not-alphanum
797 (setq prev-not-alphanum (not (alphanumericp char)))))))
800 ;;; READTABLE-CASE *PRINT-CASE*
802 (defun output-invert-symbol (pname stream)
803 (declare (simple-string pname))
806 (dotimes (i (length pname))
807 (let ((ch (schar pname i)))
808 (when (both-case-p ch)
809 (if (upper-case-p ch)
811 (setq all-upper nil)))))
812 (cond (all-upper (output-lowercase-symbol pname stream))
813 (all-lower (output-uppercase-symbol pname stream))
815 (write-string pname stream)))))
819 (let ((*readtable* (copy-readtable nil)))
820 (format t "READTABLE-CASE Input Symbol-name~@
821 ----------------------------------~%")
822 (dolist (readtable-case '(:upcase :downcase :preserve :invert))
823 (setf (readtable-case *readtable*) readtable-case)
824 (dolist (input '("ZEBRA" "Zebra" "zebra"))
825 (format t "~&:~A~16T~A~24T~A"
826 (string-upcase readtable-case)
828 (symbol-name (read-from-string input)))))))
831 (let ((*readtable* (copy-readtable nil)))
832 (format t "READTABLE-CASE *PRINT-CASE* Symbol-name Output Princ~@
833 --------------------------------------------------------~%")
834 (dolist (readtable-case '(:upcase :downcase :preserve :invert))
835 (setf (readtable-case *readtable*) readtable-case)
836 (dolist (*print-case* '(:upcase :downcase :capitalize))
837 (dolist (symbol '(|ZEBRA| |Zebra| |zebra|))
838 (format t "~&:~A~15T:~A~29T~A~42T~A~50T~A"
839 (string-upcase readtable-case)
840 (string-upcase *print-case*)
842 (prin1-to-string symbol)
843 (princ-to-string symbol)))))))
846 ;;;; recursive objects
848 (defun output-list (list stream)
849 (descend-into (stream)
850 (write-char #\( stream)
854 (punt-print-if-too-long length stream)
855 (output-object (pop list) stream)
858 (when (or (atom list)
859 (check-for-circularity list))
860 (write-string " . " stream)
861 (output-object list stream)
863 (write-char #\space stream)
865 (write-char #\) stream)))
867 (defun output-vector (vector stream)
868 (declare (vector vector))
869 (cond ((stringp vector)
870 (cond ((and *print-readably*
871 (not (eq (array-element-type vector)
874 (make-array 0 :element-type 'character))))))
875 (error 'print-not-readable :object vector))
876 ((or *print-escape* *print-readably*)
877 (write-char #\" stream)
878 (quote-string vector stream)
879 (write-char #\" stream))
881 (write-string vector stream))))
882 ((not (or *print-array* *print-readably*))
883 (output-terse-array vector stream))
884 ((bit-vector-p vector)
885 (write-string "#*" stream)
886 (dovector (bit vector)
887 ;; (Don't use OUTPUT-OBJECT here, since this code
888 ;; has to work for all possible *PRINT-BASE* values.)
889 (write-char (if (zerop bit) #\0 #\1) stream)))
891 (when (and *print-readably*
892 (not (array-readably-printable-p vector)))
893 (error 'print-not-readable :object vector))
894 (descend-into (stream)
895 (write-string "#(" stream)
896 (dotimes (i (length vector))
898 (write-char #\space stream))
899 (punt-print-if-too-long i stream)
900 (output-object (aref vector i) stream))
901 (write-string ")" stream)))))
903 ;;; This function outputs a string quoting characters sufficiently
904 ;;; so that someone can read it in again. Basically, put a slash in
905 ;;; front of an character satisfying NEEDS-SLASH-P.
906 (defun quote-string (string stream)
907 (macrolet ((needs-slash-p (char)
908 ;; KLUDGE: We probably should look at the readtable, but just do
909 ;; this for now. [noted by anonymous long ago] -- WHN 19991130
910 `(or (char= ,char #\\)
912 (with-array-data ((data string) (start) (end (length string)))
913 (do ((index start (1+ index)))
915 (let ((char (schar data index)))
916 (when (needs-slash-p char) (write-char #\\ stream))
917 (write-char char stream))))))
919 (defun array-readably-printable-p (array)
920 (and (eq (array-element-type array) t)
921 (let ((zero (position 0 (array-dimensions array)))
922 (number (position 0 (array-dimensions array)
923 :test (complement #'eql)
925 (or (null zero) (null number) (> zero number)))))
927 ;;; Output the printed representation of any array in either the #< or #A
929 (defun output-array (array stream)
930 (if (or *print-array* *print-readably*)
931 (output-array-guts array stream)
932 (output-terse-array array stream)))
934 ;;; Output the abbreviated #< form of an array.
935 (defun output-terse-array (array stream)
936 (let ((*print-level* nil)
937 (*print-length* nil))
938 (print-unreadable-object (array stream :type t :identity t))))
940 ;;; Output the readable #A form of an array.
941 (defun output-array-guts (array stream)
942 (when (and *print-readably*
943 (not (array-readably-printable-p array)))
944 (error 'print-not-readable :object array))
945 (write-char #\# stream)
946 (let ((*print-base* 10)
948 (output-integer (array-rank array) stream))
949 (write-char #\A stream)
950 (with-array-data ((data array) (start) (end))
951 (declare (ignore end))
952 (sub-output-array-guts data (array-dimensions array) stream start)))
954 (defun sub-output-array-guts (array dimensions stream index)
955 (declare (type (simple-array * (*)) array) (fixnum index))
956 (cond ((null dimensions)
957 (output-object (aref array index) stream))
959 (descend-into (stream)
960 (write-char #\( stream)
961 (let* ((dimension (car dimensions))
962 (dimensions (cdr dimensions))
963 (count (reduce #'* dimensions)))
964 (dotimes (i dimension)
966 (write-char #\space stream))
967 (punt-print-if-too-long i stream)
968 (sub-output-array-guts array dimensions stream index)
970 (write-char #\) stream)))))
972 ;;; a trivial non-generic-function placeholder for PRINT-OBJECT, for
973 ;;; use until CLOS is set up (at which time it will be replaced with
974 ;;; the real generic function implementation)
975 (defun print-object (instance stream)
976 (default-structure-print instance stream *current-level-in-print*))
978 ;;;; integer, ratio, and complex printing (i.e. everything but floats)
980 (defun %output-radix (base stream)
981 (write-char #\# stream)
982 (write-char (case base
986 (t (%output-fixnum-in-base base 10 stream)
990 (defun %output-fixnum-in-base (n base stream)
991 (multiple-value-bind (q r)
993 ;; Recurse until you have all the digits pushed on
996 (%output-fixnum-in-base q base stream))
997 ;; Then as each recursive call unwinds, turn the
998 ;; digit (in remainder) into a character and output
1001 (schar "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ" r)
1004 ;; Algorithm by Harald Hanche-Olsen, sbcl-devel 2005-02-05
1005 (defun %output-bignum-in-base (n base stream)
1006 (declare (type bignum n) (type fixnum base))
1007 (let ((power (make-array 10 :adjustable t :fill-pointer 0)))
1008 ;; Here there be the bottleneck for big bignums, in the (* p p).
1009 ;; A special purpose SQUARE-BIGNUM might help a bit. See eg: Dan
1010 ;; Zuras, "On Squaring and Multiplying Large Integers", ARITH-11:
1011 ;; IEEE Symposium on Computer Arithmetic, 1993, pp. 260 to 271.
1012 ;; Reprinted as "More on Multiplying and Squaring Large Integers",
1013 ;; IEEE Transactions on Computers, volume 43, number 8, August
1014 ;; 1994, pp. 899-908.
1015 (do ((p base (* p p)))
1017 (vector-push-extend p power))
1018 ;; (aref power k) == (expt base (expt 2 k))
1019 (labels ((bisect (n k exactp)
1020 (declare (fixnum k))
1021 ;; N is the number to bisect
1022 ;; K on initial entry BASE^(2^K) > N
1023 ;; EXACTP is true if 2^K is the exact number of digits
1026 (loop repeat (ash 1 k) do (write-char #\0 stream))))
1029 (schar "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ" n)
1033 (multiple-value-bind (q r) (truncate n (aref power k))
1034 ;; EXACTP is NIL only at the head of the
1035 ;; initial number, as we don't know the number
1036 ;; of digits there, but we do know that it
1037 ;; doesn't get any leading zeros.
1039 (bisect r k (or exactp (plusp q))))))))
1040 (bisect n (fill-pointer power) nil))))
1042 (defun %output-integer-in-base (integer base stream)
1043 (when (minusp integer)
1044 (write-char #\- stream)
1045 (setf integer (- integer)))
1046 (if (fixnump integer)
1047 (%output-fixnum-in-base integer base stream)
1048 (%output-bignum-in-base integer base stream)))
1050 (defun output-integer (integer stream)
1051 (let ((base *print-base*))
1052 (when (and (/= base 10) *print-radix*)
1053 (%output-radix base stream))
1054 (%output-integer-in-base integer base stream)
1055 (when (and *print-radix* (= base 10))
1056 (write-char #\. stream))))
1058 (defun output-ratio (ratio stream)
1059 (let ((base *print-base*))
1061 (%output-radix base stream))
1062 (%output-integer-in-base (numerator ratio) base stream)
1063 (write-char #\/ stream)
1064 (%output-integer-in-base (denominator ratio) base stream)))
1066 (defun output-complex (complex stream)
1067 (write-string "#C(" stream)
1068 ;; FIXME: Could this just be OUTPUT-NUMBER?
1069 (output-object (realpart complex) stream)
1070 (write-char #\space stream)
1071 (output-object (imagpart complex) stream)
1072 (write-char #\) stream))
1076 ;;; FLONUM-TO-STRING (and its subsidiary function FLOAT-STRING) does
1077 ;;; most of the work for all printing of floating point numbers in
1078 ;;; FORMAT. It converts a floating point number to a string in a free
1079 ;;; or fixed format with no exponent. The interpretation of the
1080 ;;; arguments is as follows:
1082 ;;; X - The floating point number to convert, which must not be
1084 ;;; WIDTH - The preferred field width, used to determine the number
1085 ;;; of fraction digits to produce if the FDIGITS parameter
1086 ;;; is unspecified or NIL. If the non-fraction digits and the
1087 ;;; decimal point alone exceed this width, no fraction digits
1088 ;;; will be produced unless a non-NIL value of FDIGITS has been
1089 ;;; specified. Field overflow is not considerd an error at this
1091 ;;; FDIGITS - The number of fractional digits to produce. Insignificant
1092 ;;; trailing zeroes may be introduced as needed. May be
1093 ;;; unspecified or NIL, in which case as many digits as possible
1094 ;;; are generated, subject to the constraint that there are no
1095 ;;; trailing zeroes.
1096 ;;; SCALE - If this parameter is specified or non-NIL, then the number
1097 ;;; printed is (* x (expt 10 scale)). This scaling is exact,
1098 ;;; and cannot lose precision.
1099 ;;; FMIN - This parameter, if specified or non-NIL, is the minimum
1100 ;;; number of fraction digits which will be produced, regardless
1101 ;;; of the value of WIDTH or FDIGITS. This feature is used by
1102 ;;; the ~E format directive to prevent complete loss of
1103 ;;; significance in the printed value due to a bogus choice of
1107 ;;; (VALUES DIGIT-STRING DIGIT-LENGTH LEADING-POINT TRAILING-POINT DECPNT)
1108 ;;; where the results have the following interpretation:
1110 ;;; DIGIT-STRING - The decimal representation of X, with decimal point.
1111 ;;; DIGIT-LENGTH - The length of the string DIGIT-STRING.
1112 ;;; LEADING-POINT - True if the first character of DIGIT-STRING is the
1114 ;;; TRAILING-POINT - True if the last character of DIGIT-STRING is the
1116 ;;; POINT-POS - The position of the digit preceding the decimal
1117 ;;; point. Zero indicates point before first digit.
1119 ;;; NOTE: FLONUM-TO-STRING goes to a lot of trouble to guarantee
1120 ;;; accuracy. Specifically, the decimal number printed is the closest
1121 ;;; possible approximation to the true value of the binary number to
1122 ;;; be printed from among all decimal representations with the same
1123 ;;; number of digits. In free-format output, i.e. with the number of
1124 ;;; digits unconstrained, it is guaranteed that all the information is
1125 ;;; preserved, so that a properly- rounding reader can reconstruct the
1126 ;;; original binary number, bit-for-bit, from its printed decimal
1127 ;;; representation. Furthermore, only as many digits as necessary to
1128 ;;; satisfy this condition will be printed.
1130 ;;; FLOAT-DIGITS actually generates the digits for positive numbers;
1131 ;;; see below for comments.
1133 (defun flonum-to-string (x &optional width fdigits scale fmin)
1134 (declare (type float x))
1135 ;; FIXME: I think only FORMAT-DOLLARS calls FLONUM-TO-STRING with
1136 ;; possibly-negative X.
1139 ;; Zero is a special case which FLOAT-STRING cannot handle.
1141 (let ((s (make-string (1+ fdigits) :initial-element #\0)))
1142 (setf (schar s 0) #\.)
1143 (values s (length s) t (zerop fdigits) 0))
1144 (values "." 1 t t 0)))
1146 (multiple-value-bind (e string)
1148 (flonum-to-digits x (min (- fdigits) (- (or fmin 0))))
1149 (if (and width (> width 1))
1150 (let ((w (multiple-value-list (flonum-to-digits x (1- width) t)))
1151 (f (multiple-value-list (flonum-to-digits x (- (or fmin 0))))))
1153 ((>= (length (cadr w)) (length (cadr f)))
1155 (t (values-list f))))
1156 (flonum-to-digits x)))
1157 (let ((e (+ e (or scale 0)))
1158 (stream (make-string-output-stream)))
1161 (write-string string stream :end (min (length string) e))
1162 (dotimes (i (- e (length string)))
1163 (write-char #\0 stream))
1164 (write-char #\. stream)
1165 (write-string string stream :start (min (length string) e))
1167 (dotimes (i (- fdigits
1169 (min (length string) e))))
1170 (write-char #\0 stream))))
1172 (write-string "." stream)
1174 (write-char #\0 stream))
1175 (write-string string stream)
1177 (dotimes (i (+ fdigits e (- (length string))))
1178 (write-char #\0 stream)))))
1179 (let ((string (get-output-stream-string stream)))
1180 (values string (length string)
1181 (char= (char string 0) #\.)
1182 (char= (char string (1- (length string))) #\.)
1183 (position #\. string))))))))
1185 ;;; implementation of figure 1 from Burger and Dybvig, 1996. As the
1186 ;;; implementation of the Dragon from Classic CMUCL (and previously in
1187 ;;; SBCL above FLONUM-TO-STRING) says: "DO NOT EVEN THINK OF
1188 ;;; ATTEMPTING TO UNDERSTAND THIS CODE WITHOUT READING THE PAPER!",
1189 ;;; and in this case we have to add that even reading the paper might
1190 ;;; not bring immediate illumination as CSR has attempted to turn
1191 ;;; idiomatic Scheme into idiomatic Lisp.
1193 ;;; FIXME: figure 1 from Burger and Dybvig is the unoptimized
1194 ;;; algorithm, noticeably slow at finding the exponent. Figure 2 has
1195 ;;; an improved algorithm, but CSR ran out of energy.
1197 ;;; possible extension for the enthusiastic: printing floats in bases
1198 ;;; other than base 10.
1199 (defconstant single-float-min-e
1200 (nth-value 1 (decode-float least-positive-single-float)))
1201 (defconstant double-float-min-e
1202 (nth-value 1 (decode-float least-positive-double-float)))
1204 (defconstant long-float-min-e
1205 (nth-value 1 (decode-float least-positive-long-float)))
1207 (defun flonum-to-digits (v &optional position relativep)
1208 (let ((print-base 10) ; B
1210 (float-digits (float-digits v)) ; p
1211 (digit-characters "0123456789")
1214 (single-float single-float-min-e)
1215 (double-float double-float-min-e)
1217 (long-float long-float-min-e))))
1218 (multiple-value-bind (f e)
1219 (integer-decode-float v)
1220 (let (;; FIXME: these even tests assume normal IEEE rounding
1221 ;; mode. I wonder if we should cater for non-normal?
1224 (result (make-array 50 :element-type 'base-char
1225 :fill-pointer 0 :adjustable t)))
1226 (labels ((scale (r s m+ m-)
1228 (s s (* s print-base)))
1229 ((not (or (> (+ r m+) s)
1230 (and high-ok (= (+ r m+) s))))
1232 (r r (* r print-base))
1233 (m+ m+ (* m+ print-base))
1234 (m- m- (* m- print-base)))
1235 ((not (or (< (* (+ r m+) print-base) s)
1237 (= (* (+ r m+) print-base) s))))
1238 (values k (generate r s m+ m-)))))))
1239 (generate (r s m+ m-)
1243 (setf (values d r) (truncate (* r print-base) s))
1244 (setf m+ (* m+ print-base))
1245 (setf m- (* m- print-base))
1246 (setf tc1 (or (< r m-) (and low-ok (= r m-))))
1247 (setf tc2 (or (> (+ r m+) s)
1248 (and high-ok (= (+ r m+) s))))
1251 (vector-push-extend (char digit-characters d) result)
1255 ((and (not tc1) tc2) (1+ d))
1256 ((and tc1 (not tc2)) d)
1258 (if (< (* r 2) s) d (1+ d))))))
1259 (vector-push-extend (char digit-characters d) result)
1260 (return-from generate result)))))
1264 (let* ((be (expt float-radix e))
1265 (be1 (* be float-radix)))
1266 (if (/= f (expt float-radix (1- float-digits)))
1276 (/= f (expt float-radix (1- float-digits))))
1278 s (* (expt float-radix (- e)) 2)
1281 (setf r (* f float-radix 2)
1282 s (* (expt float-radix (- 1 e)) 2)
1287 (aver (> position 0))
1289 ;; running out of letters here
1290 (l 1 (* l print-base)))
1291 ((>= (* s l) (+ r m+))
1293 (if (< (+ r (* s (/ (expt print-base (- k position)) 2)))
1294 (* s (expt print-base k)))
1295 (setf position (- k position))
1296 (setf position (- k position 1))))))
1297 (let ((low (max m- (/ (* s (expt print-base position)) 2)))
1298 (high (max m+ (/ (* s (expt print-base position)) 2))))
1305 (values r s m+ m-))))
1306 (multiple-value-bind (r s m+ m-) (initialize)
1307 (scale r s m+ m-)))))))
1309 ;;; Given a non-negative floating point number, SCALE-EXPONENT returns
1310 ;;; a new floating point number Z in the range (0.1, 1.0] and an
1311 ;;; exponent E such that Z * 10^E is (approximately) equal to the
1312 ;;; original number. There may be some loss of precision due the
1313 ;;; floating point representation. The scaling is always done with
1314 ;;; long float arithmetic, which helps printing of lesser precisions
1315 ;;; as well as avoiding generic arithmetic.
1317 ;;; When computing our initial scale factor using EXPT, we pull out
1318 ;;; part of the computation to avoid over/under flow. When
1319 ;;; denormalized, we must pull out a large factor, since there is more
1320 ;;; negative exponent range than positive range.
1322 (eval-when (:compile-toplevel :execute)
1323 (setf *read-default-float-format*
1324 #!+long-float 'long-float #!-long-float 'double-float))
1325 (defun scale-exponent (original-x)
1326 (let* ((x (coerce original-x 'long-float)))
1327 (multiple-value-bind (sig exponent) (decode-float x)
1328 (declare (ignore sig))
1330 (values (float 0.0e0 original-x) 1)
1331 (let* ((ex (locally (declare (optimize (safety 0)))
1333 (round (* exponent (log 2e0 10))))))
1335 (if (float-denormalized-p x)
1337 (* x 1.0e16 (expt 10.0e0 (- (- ex) 16)))
1339 (* x 1.0e18 (expt 10.0e0 (- (- ex) 18)))
1340 (* x 10.0e0 (expt 10.0e0 (- (- ex) 1))))
1341 (/ x 10.0e0 (expt 10.0e0 (1- ex))))))
1342 (do ((d 10.0e0 (* d 10.0e0))
1346 (do ((m 10.0e0 (* m 10.0e0))
1350 (values (float z original-x) ex))
1351 (declare (long-float m) (integer ex))))
1352 (declare (long-float d))))))))
1353 (eval-when (:compile-toplevel :execute)
1354 (setf *read-default-float-format* 'single-float))
1356 ;;;; entry point for the float printer
1358 ;;; the float printer as called by PRINT, PRIN1, PRINC, etc. The
1359 ;;; argument is printed free-format, in either exponential or
1360 ;;; non-exponential notation, depending on its magnitude.
1362 ;;; NOTE: When a number is to be printed in exponential format, it is
1363 ;;; scaled in floating point. Since precision may be lost in this
1364 ;;; process, the guaranteed accuracy properties of FLONUM-TO-STRING
1365 ;;; are lost. The difficulty is that FLONUM-TO-STRING performs
1366 ;;; extensive computations with integers of similar magnitude to that
1367 ;;; of the number being printed. For large exponents, the bignums
1368 ;;; really get out of hand. If bignum arithmetic becomes reasonably
1369 ;;; fast and the exponent range is not too large, then it might become
1370 ;;; attractive to handle exponential notation with the same accuracy
1371 ;;; as non-exponential notation, using the method described in the
1372 ;;; Steele and White paper.
1374 ;;; NOTE II: this has been bypassed slightly by implementing Burger
1375 ;;; and Dybvig, 1996. When someone has time (KLUDGE) they can
1376 ;;; probably (a) implement the optimizations suggested by Burger and
1377 ;;; Dyvbig, and (b) remove all vestiges of Dragon4, including from
1378 ;;; fixed-format printing.
1380 ;;; Print the appropriate exponent marker for X and the specified exponent.
1381 (defun print-float-exponent (x exp stream)
1382 (declare (type float x) (type integer exp) (type stream stream))
1383 (let ((*print-radix* nil)
1384 (plusp (plusp exp)))
1385 (if (typep x *read-default-float-format*)
1387 (format stream "e~:[~;+~]~D" plusp exp))
1388 (format stream "~C~:[~;+~]~D"
1396 (defun output-float-infinity (x stream)
1397 (declare (float x) (stream stream))
1399 (write-string "#." stream))
1401 (error 'print-not-readable :object x))
1403 (write-string "#<" stream)))
1404 (write-string "SB-EXT:" stream)
1405 (write-string (symbol-name (float-format-name x)) stream)
1406 (write-string (if (plusp x) "-POSITIVE-" "-NEGATIVE-")
1408 (write-string "INFINITY" stream)
1410 (write-string ">" stream)))
1412 (defun output-float-nan (x stream)
1413 (print-unreadable-object (x stream)
1414 (princ (float-format-name x) stream)
1415 (write-string (if (float-trapping-nan-p x) " trapping" " quiet") stream)
1416 (write-string " NaN" stream)))
1418 ;;; the function called by OUTPUT-OBJECT to handle floats
1419 (defun output-float (x stream)
1421 ((float-infinity-p x)
1422 (output-float-infinity x stream))
1424 (output-float-nan x stream))
1426 (let ((x (cond ((minusp (float-sign x))
1427 (write-char #\- stream)
1433 (write-string "0.0" stream)
1434 (print-float-exponent x 0 stream))
1436 (output-float-aux x stream -3 8)))))))
1437 (defun output-float-aux (x stream e-min e-max)
1438 (multiple-value-bind (e string)
1439 (flonum-to-digits x)
1444 (write-string string stream :end (min (length string) e))
1445 (dotimes (i (- e (length string)))
1446 (write-char #\0 stream))
1447 (write-char #\. stream)
1448 (write-string string stream :start (min (length string) e))
1449 (when (<= (length string) e)
1450 (write-char #\0 stream))
1451 (print-float-exponent x 0 stream))
1453 (write-string "0." stream)
1455 (write-char #\0 stream))
1456 (write-string string stream)
1457 (print-float-exponent x 0 stream))))
1458 (t (write-string string stream :end 1)
1459 (write-char #\. stream)
1460 (write-string string stream :start 1)
1461 (when (= (length string) 1)
1462 (write-char #\0 stream))
1463 (print-float-exponent x (1- e) stream)))))
1465 ;;;; other leaf objects
1467 ;;; If *PRINT-ESCAPE* is false, just do a WRITE-CHAR, otherwise output
1468 ;;; the character name or the character in the #\char format.
1469 (defun output-character (char stream)
1470 (if (or *print-escape* *print-readably*)
1471 (let ((graphicp (graphic-char-p char))
1472 (name (char-name char)))
1473 (write-string "#\\" stream)
1474 (if (and name (not graphicp))
1475 (quote-string name stream)
1476 (write-char char stream)))
1477 (write-char char stream)))
1479 (defun output-sap (sap stream)
1480 (declare (type system-area-pointer sap))
1482 (format stream "#.(~S #X~8,'0X)" 'int-sap (sap-int sap)))
1484 (print-unreadable-object (sap stream)
1485 (format stream "system area pointer: #X~8,'0X" (sap-int sap))))))
1487 (defun output-weak-pointer (weak-pointer stream)
1488 (declare (type weak-pointer weak-pointer))
1489 (print-unreadable-object (weak-pointer stream)
1490 (multiple-value-bind (value validp) (weak-pointer-value weak-pointer)
1492 (write-string "weak pointer: " stream)
1493 (write value :stream stream))
1495 (write-string "broken weak pointer" stream))))))
1497 (defun output-code-component (component stream)
1498 (print-unreadable-object (component stream :identity t)
1499 (let ((dinfo (%code-debug-info component)))
1500 (cond ((eq dinfo :bogus-lra)
1501 (write-string "bogus code object" stream))
1503 (write-string "code object" stream)
1505 (write-char #\space stream)
1506 (output-object (sb!c::debug-info-name dinfo) stream)))))))
1508 (defun output-lra (lra stream)
1509 (print-unreadable-object (lra stream :identity t)
1510 (write-string "return PC object" stream)))
1512 (defun output-fdefn (fdefn stream)
1513 (print-unreadable-object (fdefn stream)
1514 (write-string "FDEFINITION object for " stream)
1515 (output-object (fdefn-name fdefn) stream)))
1519 ;;; Output OBJECT as using PRINT-OBJECT if it's a
1520 ;;; FUNCALLABLE-STANDARD-CLASS, or return NIL otherwise.
1522 ;;; The definition here is a simple temporary placeholder. It will be
1523 ;;; overwritten by a smarter version (capable of calling generic
1524 ;;; PRINT-OBJECT when appropriate) when CLOS is installed.
1525 (defun printed-as-clos-funcallable-standard-class (object stream)
1526 (declare (ignore object stream))
1529 (defun output-fun (object stream)
1530 (let* ((*print-length* 3) ; in case we have to..
1531 (*print-level* 3) ; ..print an interpreted function definition
1532 (name (%fun-name object))
1533 (proper-name-p (and (legal-fun-name-p name) (fboundp name)
1534 (eq (fdefinition name) object))))
1535 (print-unreadable-object (object stream :identity (not proper-name-p))
1536 (format stream "~:[FUNCTION~;CLOSURE~]~@[ ~S~]"
1540 ;;;; catch-all for unknown things
1542 (defun output-random (object stream)
1543 (print-unreadable-object (object stream :identity t)
1544 (let ((lowtag (lowtag-of object)))
1546 (#.sb!vm:other-pointer-lowtag
1547 (let ((widetag (widetag-of object)))
1549 (#.sb!vm:value-cell-header-widetag
1550 (write-string "value cell " stream)
1551 (output-object (value-cell-ref object) stream))
1553 (write-string "unknown pointer object, widetag=" stream)
1554 (let ((*print-base* 16) (*print-radix* t))
1555 (output-integer widetag stream))))))
1556 ((#.sb!vm:fun-pointer-lowtag
1557 #.sb!vm:instance-pointer-lowtag
1558 #.sb!vm:list-pointer-lowtag)
1559 (write-string "unknown pointer object, lowtag=" stream)
1560 (let ((*print-base* 16) (*print-radix* t))
1561 (output-integer lowtag stream)))
1563 (case (widetag-of object)
1564 (#.sb!vm:unbound-marker-widetag
1565 (write-string "unbound marker" stream))
1567 (write-string "unknown immediate object, lowtag=" stream)
1568 (let ((*print-base* 2) (*print-radix* t))
1569 (output-integer lowtag stream))
1570 (write-string ", widetag=" stream)
1571 (let ((*print-base* 16) (*print-radix* t))
1572 (output-integer (widetag-of object) stream)))))))))