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authorVincent Ambo <tazjin@google.com>2020-01-17T18·04+0000
committerVincent Ambo <tazjin@google.com>2020-01-17T18·04+0000
commit95aeb2ebae32a01ff79644daa523bda5d8552863 (patch)
tree551a1efe85e43fe6fd963a35b9b787a04a12dce3 /doc/docstrings.lisp
Squashed 'third_party/lisp/alexandria/' content from commit fc2a2f5c
git-subtree-dir: third_party/lisp/alexandria
git-subtree-split: fc2a2f5c34147bb4e3e4a350b04220de0263710f
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+;;; -*- lisp -*-
+
+;;;; A docstring extractor for the sbcl manual.  Creates
+;;;; @include-ready documentation from the docstrings of exported
+;;;; symbols of specified packages.
+
+;;;; This software is part of the SBCL software system. SBCL is in the
+;;;; public domain and is provided with absolutely no warranty. See
+;;;; the COPYING file for more information.
+;;;;
+;;;; Written by Rudi Schlatte <rudi@constantly.at>, mangled
+;;;; by Nikodemus Siivola.
+
+;;;; TODO
+;;;; * Verbatim text
+;;;; * Quotations
+;;;; * Method documentation untested
+;;;; * Method sorting, somehow
+;;;; * Index for macros & constants?
+;;;; * This is getting complicated enough that tests would be good
+;;;; * Nesting (currently only nested itemizations work)
+;;;; * doc -> internal form -> texinfo (so that non-texinfo format are also
+;;;;   easily generated)
+
+;;;; FIXME: The description below is no longer complete. This
+;;;; should possibly be turned into a contrib with proper documentation.
+
+;;;; Formatting heuristics (tweaked to format SAVE-LISP-AND-DIE sanely):
+;;;;
+;;;; Formats SYMBOL as @code{symbol}, or @var{symbol} if symbol is in
+;;;; the argument list of the defun / defmacro.
+;;;;
+;;;; Lines starting with * or - that are followed by intented lines
+;;;; are marked up with @itemize.
+;;;;
+;;;; Lines containing only a SYMBOL that are followed by indented
+;;;; lines are marked up as @table @code, with the SYMBOL as the item.
+
+(eval-when (:compile-toplevel :load-toplevel :execute)
+  (require 'sb-introspect))
+
+(defpackage :sb-texinfo
+  (:use :cl :sb-mop)
+  (:shadow #:documentation)
+  (:export #:generate-includes #:document-package)
+  (:documentation
+   "Tools to generate TexInfo documentation from docstrings."))
+
+(in-package :sb-texinfo)
+
+;;;; various specials and parameters
+
+(defvar *texinfo-output*)
+(defvar *texinfo-variables*)
+(defvar *documentation-package*)
+(defvar *base-package*)
+
+(defparameter *undocumented-packages* '(sb-pcl sb-int sb-kernel sb-sys sb-c))
+
+(defparameter *documentation-types*
+  '(compiler-macro
+    function
+    method-combination
+    setf
+    ;;structure  ; also handled by `type'
+    type
+    variable)
+  "A list of symbols accepted as second argument of `documentation'")
+
+(defparameter *character-replacements*
+  '((#\* . "star") (#\/ . "slash") (#\+ . "plus")
+    (#\< . "lt") (#\> . "gt")
+    (#\= . "equals"))
+  "Characters and their replacement names that `alphanumize' uses. If
+the replacements contain any of the chars they're supposed to replace,
+you deserve to lose.")
+
+(defparameter *characters-to-drop* '(#\\ #\` #\')
+  "Characters that should be removed by `alphanumize'.")
+
+(defparameter *texinfo-escaped-chars* "@{}"
+  "Characters that must be escaped with #\@ for Texinfo.")
+
+(defparameter *itemize-start-characters* '(#\* #\-)
+  "Characters that might start an itemization in docstrings when
+  at the start of a line.")
+
+(defparameter *symbol-characters* "ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890*:-+&#'"
+  "List of characters that make up symbols in a docstring.")
+
+(defparameter *symbol-delimiters* " ,.!?;")
+
+(defparameter *ordered-documentation-kinds*
+  '(package type structure condition class macro))
+
+;;;; utilities
+
+(defun flatten (list)
+  (cond ((null list)
+         nil)
+        ((consp (car list))
+         (nconc (flatten (car list)) (flatten (cdr list))))
+        ((null (cdr list))
+         (cons (car list) nil))
+        (t
+         (cons (car list) (flatten (cdr list))))))
+
+(defun whitespacep (char)
+  (find char #(#\tab #\space #\page)))
+
+(defun setf-name-p (name)
+  (or (symbolp name)
+      (and (listp name) (= 2 (length name)) (eq (car name) 'setf))))
+
+(defgeneric specializer-name (specializer))
+
+(defmethod specializer-name ((specializer eql-specializer))
+  (list 'eql (eql-specializer-object specializer)))
+
+(defmethod specializer-name ((specializer class))
+  (class-name specializer))
+
+(defun ensure-class-precedence-list (class)
+  (unless (class-finalized-p class)
+    (finalize-inheritance class))
+  (class-precedence-list class))
+
+(defun specialized-lambda-list (method)
+  ;; courtecy of AMOP p. 61
+  (let* ((specializers (method-specializers method))
+         (lambda-list (method-lambda-list method))
+         (n-required (length specializers)))
+    (append (mapcar (lambda (arg specializer)
+                      (if  (eq specializer (find-class 't))
+                           arg
+                           `(,arg ,(specializer-name specializer))))
+                    (subseq lambda-list 0 n-required)
+                    specializers)
+           (subseq lambda-list n-required))))
+
+(defun string-lines (string)
+  "Lines in STRING as a vector."
+  (coerce (with-input-from-string (s string)
+            (loop for line = (read-line s nil nil)
+               while line collect line))
+          'vector))
+
+(defun indentation (line)
+  "Position of first non-SPACE character in LINE."
+  (position-if-not (lambda (c) (char= c #\Space)) line))
+
+(defun docstring (x doc-type)
+  (cl:documentation x doc-type))
+
+(defun flatten-to-string (list)
+  (format nil "~{~A~^-~}" (flatten list)))
+
+(defun alphanumize (original)
+  "Construct a string without characters like *`' that will f-star-ck
+up filename handling. See `*character-replacements*' and
+`*characters-to-drop*' for customization."
+  (let ((name (remove-if (lambda (x) (member x *characters-to-drop*))
+                         (if (listp original)
+                             (flatten-to-string original)
+                             (string original))))
+        (chars-to-replace (mapcar #'car *character-replacements*)))
+    (flet ((replacement-delimiter (index)
+             (cond ((or (< index 0) (>= index (length name))) "")
+                   ((alphanumericp (char name index)) "-")
+                   (t ""))))
+      (loop for index = (position-if #'(lambda (x) (member x chars-to-replace))
+                                     name)
+         while index
+         do (setf name (concatenate 'string (subseq name 0 index)
+                                    (replacement-delimiter (1- index))
+                                    (cdr (assoc (aref name index)
+                                                *character-replacements*))
+                                    (replacement-delimiter (1+ index))
+                                    (subseq name (1+ index))))))
+    name))
+
+;;;; generating various names
+
+(defgeneric name (thing)
+  (:documentation "Name for a documented thing. Names are either
+symbols or lists of symbols."))
+
+(defmethod name ((symbol symbol))
+  symbol)
+
+(defmethod name ((cons cons))
+  cons)
+
+(defmethod name ((package package))
+  (short-package-name package))
+
+(defmethod name ((method method))
+  (list
+   (generic-function-name (method-generic-function method))
+   (method-qualifiers method)
+   (specialized-lambda-list method)))
+
+;;; Node names for DOCUMENTATION instances
+
+(defgeneric name-using-kind/name (kind name doc))
+
+(defmethod name-using-kind/name (kind (name string) doc)
+  (declare (ignore kind doc))
+  name)
+
+(defmethod name-using-kind/name (kind (name symbol) doc)
+  (declare (ignore kind))
+  (format nil "~@[~A:~]~A" (short-package-name (get-package doc)) name))
+
+(defmethod name-using-kind/name (kind (name list) doc)
+  (declare (ignore kind))
+  (assert (setf-name-p name))
+  (format nil "(setf ~@[~A:~]~A)" (short-package-name (get-package doc)) (second name)))
+
+(defmethod name-using-kind/name ((kind (eql 'method)) name doc)
+  (format nil "~A~{ ~A~} ~A"
+          (name-using-kind/name nil (first name) doc)
+          (second name)
+          (third name)))
+
+(defun node-name (doc)
+  "Returns TexInfo node name as a string for a DOCUMENTATION instance."
+  (let ((kind (get-kind doc)))
+    (format nil "~:(~A~) ~(~A~)" kind (name-using-kind/name kind (get-name doc) doc))))
+
+(defun short-package-name (package)
+  (unless (eq package *base-package*)
+    (car (sort (copy-list (cons (package-name package) (package-nicknames package)))
+               #'< :key #'length))))
+
+;;; Definition titles for DOCUMENTATION instances
+
+(defgeneric title-using-kind/name (kind name doc))
+
+(defmethod title-using-kind/name (kind (name string) doc)
+  (declare (ignore kind doc))
+  name)
+
+(defmethod title-using-kind/name (kind (name symbol) doc)
+  (declare (ignore kind))
+  (format nil "~@[~A:~]~A" (short-package-name (get-package doc)) name))
+
+(defmethod title-using-kind/name (kind (name list) doc)
+  (declare (ignore kind))
+  (assert (setf-name-p name))
+  (format nil "(setf ~@[~A:~]~A)" (short-package-name (get-package doc)) (second name)))
+
+(defmethod title-using-kind/name ((kind (eql 'method)) name doc)
+  (format nil "~{~A ~}~A"
+          (second name)
+          (title-using-kind/name nil (first name) doc)))
+
+(defun title-name (doc)
+  "Returns a string to be used as name of the definition."
+  (string-downcase (title-using-kind/name (get-kind doc) (get-name doc) doc)))
+
+(defun include-pathname (doc)
+  (let* ((kind (get-kind doc))
+         (name (nstring-downcase
+                (if (eq 'package kind)
+                    (format nil "package-~A" (alphanumize (get-name doc)))
+                    (format nil "~A-~A-~A"
+                            (case (get-kind doc)
+                              ((function generic-function) "fun")
+                              (structure "struct")
+                              (variable "var")
+                              (otherwise (symbol-name (get-kind doc))))
+                            (alphanumize (let ((*base-package* nil))
+                                           (short-package-name (get-package doc))))
+                            (alphanumize (get-name doc)))))))
+    (make-pathname :name name  :type "texinfo")))
+
+;;;; documentation class and related methods
+
+(defclass documentation ()
+  ((name :initarg :name :reader get-name)
+   (kind :initarg :kind :reader get-kind)
+   (string :initarg :string :reader get-string)
+   (children :initarg :children :initform nil :reader get-children)
+   (package :initform *documentation-package* :reader get-package)))
+
+(defmethod print-object ((documentation documentation) stream)
+  (print-unreadable-object (documentation stream :type t)
+    (princ (list (get-kind documentation) (get-name documentation)) stream)))
+
+(defgeneric make-documentation (x doc-type string))
+
+(defmethod make-documentation ((x package) doc-type string)
+  (declare (ignore doc-type))
+  (make-instance 'documentation
+                 :name (name x)
+                 :kind 'package
+                 :string string))
+
+(defmethod make-documentation (x (doc-type (eql 'function)) string)
+  (declare (ignore doc-type))
+  (let* ((fdef (and (fboundp x) (fdefinition x)))
+         (name x)
+         (kind (cond ((and (symbolp x) (special-operator-p x))
+                      'special-operator)
+                     ((and (symbolp x) (macro-function x))
+                      'macro)
+                     ((typep fdef 'generic-function)
+                      (assert (or (symbolp name) (setf-name-p name)))
+                      'generic-function)
+                     (fdef
+                      (assert (or (symbolp name) (setf-name-p name)))
+                      'function)))
+         (children (when (eq kind 'generic-function)
+                     (collect-gf-documentation fdef))))
+    (make-instance 'documentation
+                   :name (name x)
+                   :string string
+                   :kind kind
+                   :children children)))
+
+(defmethod make-documentation ((x method) doc-type string)
+  (declare (ignore doc-type))
+  (make-instance 'documentation
+                 :name (name x)
+                 :kind 'method
+                 :string string))
+
+(defmethod make-documentation (x (doc-type (eql 'type)) string)
+  (make-instance 'documentation
+                 :name (name x)
+                 :string string
+                 :kind (etypecase (find-class x nil)
+                         (structure-class 'structure)
+                         (standard-class 'class)
+                         (sb-pcl::condition-class 'condition)
+                         ((or built-in-class null) 'type))))
+
+(defmethod make-documentation (x (doc-type (eql 'variable)) string)
+  (make-instance 'documentation
+                 :name (name x)
+                 :string string
+                 :kind (if (constantp x)
+                           'constant
+                           'variable)))
+
+(defmethod make-documentation (x (doc-type (eql 'setf)) string)
+  (declare (ignore doc-type))
+  (make-instance 'documentation
+                 :name (name x)
+                 :kind 'setf-expander
+                 :string string))
+
+(defmethod make-documentation (x doc-type string)
+  (make-instance 'documentation
+                 :name (name x)
+                 :kind doc-type
+                 :string string))
+
+(defun maybe-documentation (x doc-type)
+  "Returns a DOCUMENTATION instance for X and DOC-TYPE, or NIL if
+there is no corresponding docstring."
+  (let ((docstring (docstring x doc-type)))
+    (when docstring
+      (make-documentation x doc-type docstring))))
+
+(defun lambda-list (doc)
+  (case (get-kind doc)
+    ((package constant variable type structure class condition nil)
+     nil)
+    (method
+     (third (get-name doc)))
+    (t
+     ;; KLUDGE: Eugh.
+     ;;
+     ;; believe it or not, the above comment was written before CSR
+     ;; came along and obfuscated this.  (2005-07-04)
+     (when (symbolp (get-name doc))
+       (labels ((clean (x &key optional key)
+                  (typecase x
+                    (atom x)
+                    ((cons (member &optional))
+                     (cons (car x) (clean (cdr x) :optional t)))
+                    ((cons (member &key))
+                     (cons (car x) (clean (cdr x) :key t)))
+                    ((cons (member &whole &environment))
+                     ;; Skip these
+                     (clean (cdr x) :optional optional :key key))
+                    ((cons cons)
+                     (cons
+                      (cond (key (if (consp (caar x))
+                                     (caaar x)
+                                     (caar x)))
+                            (optional (caar x))
+                            (t (clean (car x))))
+                      (clean (cdr x) :key key :optional optional)))
+                    (cons
+                     (cons
+                      (cond ((or key optional) (car x))
+                            (t (clean (car x))))
+                      (clean (cdr x) :key key :optional optional))))))
+         (clean (sb-introspect:function-lambda-list (get-name doc))))))))
+
+(defun get-string-name (x)
+  (let ((name (get-name x)))
+    (cond ((symbolp name)
+           (symbol-name name))
+          ((and (consp name) (eq 'setf (car name)))
+           (symbol-name (second name)))
+          ((stringp name)
+           name)
+          (t
+           (error "Don't know which symbol to use for name ~S" name)))))
+
+(defun documentation< (x y)
+  (let ((p1 (position (get-kind x) *ordered-documentation-kinds*))
+        (p2 (position (get-kind y) *ordered-documentation-kinds*)))
+    (if (or (not (and p1 p2)) (= p1 p2))
+        (string< (get-string-name x) (get-string-name y))
+        (< p1 p2))))
+
+;;;; turning text into texinfo
+
+(defun escape-for-texinfo (string &optional downcasep)
+  "Return STRING with characters in *TEXINFO-ESCAPED-CHARS* escaped
+with #\@. Optionally downcase the result."
+  (let ((result (with-output-to-string (s)
+                  (loop for char across string
+                        when (find char *texinfo-escaped-chars*)
+                        do (write-char #\@ s)
+                        do (write-char char s)))))
+    (if downcasep (nstring-downcase result) result)))
+
+(defun empty-p (line-number lines)
+  (and (< -1 line-number (length lines))
+       (not (indentation (svref lines line-number)))))
+
+;;; line markups
+
+(defvar *not-symbols* '("ANSI" "CLHS"))
+
+(defun locate-symbols (line)
+  "Return a list of index pairs of symbol-like parts of LINE."
+  ;; This would be a good application for a regex ...
+  (let (result)
+    (flet ((grab (start end)
+             (unless (member (subseq line start end) '("ANSI" "CLHS"))
+               (push (list start end) result))))
+      (do ((begin nil)
+           (maybe-begin t)
+           (i 0 (1+ i)))
+          ((= i (length line))
+           ;; symbol at end of line
+           (when (and begin (or (> i (1+ begin))
+                                (not (member (char line begin) '(#\A #\I)))))
+             (grab begin i))
+           (nreverse result))
+        (cond
+          ((and begin (find (char line i) *symbol-delimiters*))
+           ;; symbol end; remember it if it's not "A" or "I"
+           (when (or (> i (1+ begin)) (not (member (char line begin) '(#\A #\I))))
+             (grab begin i))
+           (setf begin nil
+                 maybe-begin t))
+          ((and begin (not (find (char line i) *symbol-characters*)))
+           ;; Not a symbol: abort
+           (setf begin nil))
+          ((and maybe-begin (not begin) (find (char line i) *symbol-characters*))
+           ;; potential symbol begin at this position
+           (setf begin i
+                 maybe-begin nil))
+          ((find (char line i) *symbol-delimiters*)
+           ;; potential symbol begin after this position
+           (setf maybe-begin t))
+          (t
+           ;; Not reading a symbol, not at potential start of symbol
+           (setf maybe-begin nil)))))))
+
+(defun texinfo-line (line)
+  "Format symbols in LINE texinfo-style: either as code or as
+variables if the symbol in question is contained in symbols
+*TEXINFO-VARIABLES*."
+  (with-output-to-string (result)
+    (let ((last 0))
+      (dolist (symbol/index (locate-symbols line))
+        (write-string (subseq line last (first symbol/index)) result)
+        (let ((symbol-name (apply #'subseq line symbol/index)))
+          (format result (if (member symbol-name *texinfo-variables*
+                                     :test #'string=)
+                             "@var{~A}"
+                             "@code{~A}")
+                  (string-downcase symbol-name)))
+        (setf last (second symbol/index)))
+      (write-string (subseq line last) result))))
+
+;;; lisp sections
+
+(defun lisp-section-p (line line-number lines)
+  "Returns T if the given LINE looks like start of lisp code --
+ie. if it starts with whitespace followed by a paren or
+semicolon, and the previous line is empty"
+  (let ((offset (indentation line)))
+    (and offset
+         (plusp offset)
+         (find (find-if-not #'whitespacep line) "(;")
+         (empty-p (1- line-number) lines))))
+
+(defun collect-lisp-section (lines line-number)
+  (let ((lisp (loop for index = line-number then (1+ index)
+                    for line = (and (< index (length lines)) (svref lines index))
+                    while (indentation line)
+                    collect line)))
+    (values (length lisp) `("@lisp" ,@lisp "@end lisp"))))
+
+;;; itemized sections
+
+(defun maybe-itemize-offset (line)
+  "Return NIL or the indentation offset if LINE looks like it starts
+an item in an itemization."
+  (let* ((offset (indentation line))
+         (char (when offset (char line offset))))
+    (and offset
+         (member char *itemize-start-characters* :test #'char=)
+         (char= #\Space (find-if-not (lambda (c) (char= c char))
+                                     line :start offset))
+         offset)))
+
+(defun collect-maybe-itemized-section (lines starting-line)
+  ;; Return index of next line to be processed outside
+  (let ((this-offset (maybe-itemize-offset (svref lines starting-line)))
+        (result nil)
+        (lines-consumed 0))
+    (loop for line-number from starting-line below (length lines)
+       for line = (svref lines line-number)
+       for indentation = (indentation line)
+       for offset = (maybe-itemize-offset line)
+       do (cond
+            ((not indentation)
+             ;; empty line -- inserts paragraph.
+             (push "" result)
+             (incf lines-consumed))
+            ((and offset (> indentation this-offset))
+             ;; nested itemization -- handle recursively
+             ;; FIXME: tables in itemizations go wrong
+             (multiple-value-bind (sub-lines-consumed sub-itemization)
+                 (collect-maybe-itemized-section lines line-number)
+               (when sub-lines-consumed
+                 (incf line-number (1- sub-lines-consumed)) ; +1 on next loop
+                 (incf lines-consumed sub-lines-consumed)
+                 (setf result (nconc (nreverse sub-itemization) result)))))
+            ((and offset (= indentation this-offset))
+             ;; start of new item
+             (push (format nil "@item ~A"
+                           (texinfo-line (subseq line (1+ offset))))
+                   result)
+             (incf lines-consumed))
+            ((and (not offset) (> indentation this-offset))
+             ;; continued item from previous line
+             (push (texinfo-line line) result)
+             (incf lines-consumed))
+            (t
+             ;; end of itemization
+             (loop-finish))))
+    ;; a single-line itemization isn't.
+    (if (> (count-if (lambda (line) (> (length line) 0)) result) 1)
+        (values lines-consumed `("@itemize" ,@(reverse result) "@end itemize"))
+        nil)))
+
+;;; table sections
+
+(defun tabulation-body-p (offset line-number lines)
+  (when (< line-number (length lines))
+    (let ((offset2 (indentation (svref lines line-number))))
+      (and offset2 (< offset offset2)))))
+
+(defun tabulation-p (offset line-number lines direction)
+  (let ((step  (ecase direction
+                 (:backwards (1- line-number))
+                 (:forwards (1+ line-number)))))
+    (when (and (plusp line-number) (< line-number (length lines)))
+      (and (eql offset (indentation (svref lines line-number)))
+           (or (when (eq direction :backwards)
+                 (empty-p step lines))
+               (tabulation-p offset step lines direction)
+               (tabulation-body-p offset step lines))))))
+
+(defun maybe-table-offset (line-number lines)
+  "Return NIL or the indentation offset if LINE looks like it starts
+an item in a tabulation. Ie, if it is (1) indented, (2) preceded by an
+empty line, another tabulation label, or a tabulation body, (3) and
+followed another tabulation label or a tabulation body."
+  (let* ((line (svref lines line-number))
+         (offset (indentation line))
+         (prev (1- line-number))
+         (next (1+ line-number)))
+    (when (and offset (plusp offset))
+      (and (or (empty-p prev lines)
+               (tabulation-body-p offset prev lines)
+               (tabulation-p offset prev lines :backwards))
+           (or (tabulation-body-p offset next lines)
+               (tabulation-p offset next lines :forwards))
+           offset))))
+
+;;; FIXME: This and itemization are very similar: could they share
+;;; some code, mayhap?
+
+(defun collect-maybe-table-section (lines starting-line)
+  ;; Return index of next line to be processed outside
+  (let ((this-offset (maybe-table-offset starting-line lines))
+        (result nil)
+        (lines-consumed 0))
+    (loop for line-number from starting-line below (length lines)
+          for line = (svref lines line-number)
+          for indentation = (indentation line)
+          for offset = (maybe-table-offset line-number lines)
+          do (cond
+               ((not indentation)
+                ;; empty line -- inserts paragraph.
+                (push "" result)
+                (incf lines-consumed))
+               ((and offset (= indentation this-offset))
+                ;; start of new item, or continuation of previous item
+                (if (and result (search "@item" (car result) :test #'char=))
+                    (push (format nil "@itemx ~A" (texinfo-line line))
+                          result)
+                    (progn
+                      (push "" result)
+                      (push (format nil "@item ~A" (texinfo-line line))
+                            result)))
+                (incf lines-consumed))
+               ((> indentation this-offset)
+                ;; continued item from previous line
+                (push (texinfo-line line) result)
+                (incf lines-consumed))
+               (t
+                ;; end of itemization
+                (loop-finish))))
+     ;; a single-line table isn't.
+    (if (> (count-if (lambda (line) (> (length line) 0)) result) 1)
+        (values lines-consumed
+                `("" "@table @emph" ,@(reverse result) "@end table" ""))
+        nil)))
+
+;;; section markup
+
+(defmacro with-maybe-section (index &rest forms)
+  `(multiple-value-bind (count collected) (progn ,@forms)
+    (when count
+      (dolist (line collected)
+        (write-line line *texinfo-output*))
+      (incf ,index (1- count)))))
+
+(defun write-texinfo-string (string &optional lambda-list)
+  "Try to guess as much formatting for a raw docstring as possible."
+  (let ((*texinfo-variables* (flatten lambda-list))
+        (lines (string-lines (escape-for-texinfo string nil))))
+      (loop for line-number from 0 below (length lines)
+            for line = (svref lines line-number)
+            do (cond
+                 ((with-maybe-section line-number
+                    (and (lisp-section-p line line-number lines)
+                         (collect-lisp-section lines line-number))))
+                 ((with-maybe-section line-number
+                    (and (maybe-itemize-offset line)
+                         (collect-maybe-itemized-section lines line-number))))
+                 ((with-maybe-section line-number
+                    (and (maybe-table-offset line-number lines)
+                         (collect-maybe-table-section lines line-number))))
+                 (t
+                  (write-line (texinfo-line line) *texinfo-output*))))))
+
+;;;; texinfo formatting tools
+
+(defun hide-superclass-p (class-name super-name)
+  (let ((super-package (symbol-package super-name)))
+    (or
+     ;; KLUDGE: We assume that we don't want to advertise internal
+     ;; classes in CP-lists, unless the symbol we're documenting is
+     ;; internal as well.
+     (and (member super-package #.'(mapcar #'find-package *undocumented-packages*))
+          (not (eq super-package (symbol-package class-name))))
+     ;; KLUDGE: We don't generally want to advertise SIMPLE-ERROR or
+     ;; SIMPLE-CONDITION in the CPLs of conditions that inherit them
+     ;; simply as a matter of convenience. The assumption here is that
+     ;; the inheritance is incidental unless the name of the condition
+     ;; begins with SIMPLE-.
+     (and (member super-name '(simple-error simple-condition))
+          (let ((prefix "SIMPLE-"))
+            (mismatch prefix (string class-name) :end2 (length prefix)))
+          t ; don't return number from MISMATCH
+          ))))
+
+(defun hide-slot-p (symbol slot)
+  ;; FIXME: There is no pricipal reason to avoid the slot docs fo
+  ;; structures and conditions, but their DOCUMENTATION T doesn't
+  ;; currently work with them the way we'd like.
+  (not (and (typep (find-class symbol nil) 'standard-class)
+            (docstring slot t))))
+
+(defun texinfo-anchor (doc)
+  (format *texinfo-output* "@anchor{~A}~%" (node-name doc)))
+
+;;; KLUDGE: &AUX *PRINT-PRETTY* here means "no linebreaks please"
+(defun texinfo-begin (doc &aux *print-pretty*)
+  (let ((kind (get-kind doc)))
+    (format *texinfo-output* "@~A {~:(~A~)} ~({~A}~@[ ~{~A~^ ~}~]~)~%"
+            (case kind
+              ((package constant variable)
+               "defvr")
+              ((structure class condition type)
+               "deftp")
+              (t
+               "deffn"))
+            (map 'string (lambda (char) (if (eql char #\-) #\Space char)) (string kind))
+            (title-name doc)
+            ;; &foo would be amusingly bold in the pdf thanks to TeX/Texinfo
+            ;; interactions,so we escape the ampersand -- amusingly for TeX.
+            ;; sbcl.texinfo defines macros that expand @&key and friends to &key.
+            (mapcar (lambda (name)
+                      (if (member name lambda-list-keywords)
+                          (format nil "@~A" name)
+                          name))
+                    (lambda-list doc)))))
+
+(defun texinfo-index (doc)
+  (let ((title (title-name doc)))
+    (case (get-kind doc)
+      ((structure type class condition)
+       (format *texinfo-output* "@tindex ~A~%" title))
+      ((variable constant)
+       (format *texinfo-output* "@vindex ~A~%" title))
+      ((compiler-macro function method-combination macro generic-function)
+       (format *texinfo-output* "@findex ~A~%" title)))))
+
+(defun texinfo-inferred-body (doc)
+  (when (member (get-kind doc) '(class structure condition))
+    (let ((name (get-name doc)))
+      ;; class precedence list
+      (format *texinfo-output* "Class precedence list: @code{~(~{@lw{~A}~^, ~}~)}~%~%"
+              (remove-if (lambda (class)  (hide-superclass-p name class))
+                         (mapcar #'class-name (ensure-class-precedence-list (find-class name)))))
+      ;; slots
+      (let ((slots (remove-if (lambda (slot) (hide-slot-p name slot))
+                              (class-direct-slots (find-class name)))))
+        (when slots
+          (format *texinfo-output* "Slots:~%@itemize~%")
+          (dolist (slot slots)
+            (format *texinfo-output*
+                    "@item ~(@code{~A}~#[~:; --- ~]~
+                      ~:{~2*~@[~2:*~A~P: ~{@code{@w{~S}}~^, ~}~]~:^; ~}~)~%~%"
+                    (slot-definition-name slot)
+                    (remove
+                     nil
+                     (mapcar
+                      (lambda (name things)
+                        (if things
+                            (list name (length things) things)))
+                      '("initarg" "reader"  "writer")
+                      (list
+                       (slot-definition-initargs slot)
+                       (slot-definition-readers slot)
+                       (slot-definition-writers slot)))))
+            ;; FIXME: Would be neater to handler as children
+            (write-texinfo-string (docstring slot t)))
+          (format *texinfo-output* "@end itemize~%~%"))))))
+
+(defun texinfo-body (doc)
+  (write-texinfo-string (get-string doc)))
+
+(defun texinfo-end (doc)
+  (write-line (case (get-kind doc)
+                ((package variable constant) "@end defvr")
+                ((structure type class condition) "@end deftp")
+                (t "@end deffn"))
+              *texinfo-output*))
+
+(defun write-texinfo (doc)
+  "Writes TexInfo for a DOCUMENTATION instance to *TEXINFO-OUTPUT*."
+  (texinfo-anchor doc)
+  (texinfo-begin doc)
+  (texinfo-index doc)
+  (texinfo-inferred-body doc)
+  (texinfo-body doc)
+  (texinfo-end doc)
+  ;; FIXME: Children should be sorted one way or another
+  (mapc #'write-texinfo (get-children doc)))
+
+;;;; main logic
+
+(defun collect-gf-documentation (gf)
+  "Collects method documentation for the generic function GF"
+  (loop for method in (generic-function-methods gf)
+        for doc = (maybe-documentation method t)
+        when doc
+        collect doc))
+
+(defun collect-name-documentation (name)
+  (loop for type in *documentation-types*
+        for doc = (maybe-documentation name type)
+        when doc
+        collect doc))
+
+(defun collect-symbol-documentation (symbol)
+  "Collects all docs for a SYMBOL and (SETF SYMBOL), returns a list of
+the form DOC instances. See `*documentation-types*' for the possible
+values of doc-type."
+  (nconc (collect-name-documentation symbol)
+         (collect-name-documentation (list 'setf symbol))))
+
+(defun collect-documentation (package)
+  "Collects all documentation for all external symbols of the given
+package, as well as for the package itself."
+  (let* ((*documentation-package* (find-package package))
+         (docs nil))
+    (check-type package package)
+    (do-external-symbols (symbol package)
+      (setf docs (nconc (collect-symbol-documentation symbol) docs)))
+    (let ((doc (maybe-documentation *documentation-package* t)))
+      (when doc
+        (push doc docs)))
+    docs))
+
+(defmacro with-texinfo-file (pathname &body forms)
+  `(with-open-file (*texinfo-output* ,pathname
+                                    :direction :output
+                                    :if-does-not-exist :create
+                                    :if-exists :supersede)
+    ,@forms))
+
+(defun write-ifnottex ()
+  ;; We use @&key, etc to escape & from TeX in lambda lists -- so we need to
+  ;; define them for info as well.
+  (flet ((macro (name)
+                 (let ((string (string-downcase name)))
+                   (format *texinfo-output* "@macro ~A~%~A~%@end macro~%" string string))))
+    (macro '&allow-other-keys)
+    (macro '&optional)
+    (macro '&rest)
+    (macro '&key)
+    (macro '&body)))
+
+(defun generate-includes (directory packages &key (base-package :cl-user))
+  "Create files in `directory' containing Texinfo markup of all
+docstrings of each exported symbol in `packages'. `directory' is
+created if necessary. If you supply a namestring that doesn't end in a
+slash, you lose. The generated files are of the form
+\"<doc-type>_<packagename>_<symbol-name>.texinfo\" and can be included
+via @include statements. Texinfo syntax-significant characters are
+escaped in symbol names, but if a docstring contains invalid Texinfo
+markup, you lose."
+  (handler-bind ((warning #'muffle-warning))
+    (let ((directory (merge-pathnames (pathname directory)))
+          (*base-package* (find-package base-package)))
+      (ensure-directories-exist directory)
+      (dolist (package packages)
+        (dolist (doc (collect-documentation (find-package package)))
+          (with-texinfo-file (merge-pathnames (include-pathname doc) directory)
+            (write-texinfo doc))))
+      (with-texinfo-file (merge-pathnames "ifnottex.texinfo" directory)
+        (write-ifnottex))
+      directory)))
+
+(defun document-package (package &optional filename)
+  "Create a file containing all available documentation for the
+exported symbols of `package' in Texinfo format. If `filename' is not
+supplied, a file \"<packagename>.texinfo\" is generated.
+
+The definitions can be referenced using Texinfo statements like
+@ref{<doc-type>_<packagename>_<symbol-name>.texinfo}. Texinfo
+syntax-significant characters are escaped in symbol names, but if a
+docstring contains invalid Texinfo markup, you lose."
+  (handler-bind ((warning #'muffle-warning))
+    (let* ((package (find-package package))
+           (filename (or filename (make-pathname
+                                   :name (string-downcase (short-package-name package))
+                                   :type "texinfo")))
+           (docs (sort (collect-documentation package) #'documentation<)))
+      (with-texinfo-file filename
+        (dolist (doc docs)
+          (write-texinfo doc)))
+      filename)))