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authorLeo Liu <[email protected]>2016-10-07 19:37:19 +0800
committerLeo Liu <[email protected]>2016-10-25 16:58:19 +0800
commitcec4b8ac171686b53ff730c23d90ef25039e6791 (patch)
tree810828ab824814b9df9e3f80db2177e0cb1adf3b /lib/tools/emacs
parent16b6c991cc841ced6be466eca774dba1188f8640 (diff)
downloadotp-cec4b8ac171686b53ff730c23d90ef25039e6791.tar.gz
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New commands to ease looking up OTP documentation
- erldoc-browse: open the manual entry for an MFA in the browser - erldoc-apropos: list MFAs containing a substring - erldoc-browse-topic: open user guides in the browser
Diffstat (limited to 'lib/tools/emacs')
-rw-r--r--lib/tools/emacs/Makefile1
-rw-r--r--lib/tools/emacs/erlang-start.el14
-rw-r--r--lib/tools/emacs/erlang.el5
-rw-r--r--lib/tools/emacs/erldoc.el508
4 files changed, 528 insertions, 0 deletions
diff --git a/lib/tools/emacs/Makefile b/lib/tools/emacs/Makefile
index e1b195ef97..35c93ba4ed 100644
--- a/lib/tools/emacs/Makefile
+++ b/lib/tools/emacs/Makefile
@@ -38,6 +38,7 @@ MAN_FILES= \
tags.3
EMACS_FILES= \
+ erldoc \
erlang-skels \
erlang-skels-old \
erlang_appwiz \
diff --git a/lib/tools/emacs/erlang-start.el b/lib/tools/emacs/erlang-start.el
index f9a6d24b2c..160057e179 100644
--- a/lib/tools/emacs/erlang-start.el
+++ b/lib/tools/emacs/erlang-start.el
@@ -78,9 +78,23 @@
(autoload 'erlang-find-tag-other-window "erlang"
"Like `find-tag-other-window'. Capable of retreiving Erlang modules.")
+;;
+;; Declare functions in "erlang-edoc.el".
+;;
+
(autoload 'erlang-edoc-mode "erlang-edoc" "Toggle Erlang-Edoc mode on or off." t)
;;
+;; Declare functions in "erldoc.el".
+;;
+
+(autoload 'erldoc-browse "erldoc" "\n\n(fn MFA)" t nil)
+(autoload 'erldoc-browse-topic "erldoc" "\n\n(fn TOPIC)" t nil)
+(autoload 'erldoc-apropos "erldoc" "\n\n(fn PATTERN)" t nil)
+(autoload 'erldoc-eldoc-function "erldoc" "\
+A function suitable for `eldoc-documentation-function'.\n\n(fn)" nil nil)
+
+;;
;; Associate files extensions ".erl" and ".hrl" with Erlang mode.
;;
diff --git a/lib/tools/emacs/erlang.el b/lib/tools/emacs/erlang.el
index cc22903e7f..40f0bb7f80 100644
--- a/lib/tools/emacs/erlang.el
+++ b/lib/tools/emacs/erlang.el
@@ -1440,6 +1440,11 @@ Other commands:
(erlang-skel-init)
(when (fboundp 'tempo-use-tag-list)
(tempo-use-tag-list 'erlang-tempo-tags))
+ (when (and (fboundp 'add-function) (fboundp 'erldoc-eldoc-function))
+ (or eldoc-documentation-function
+ (setq-local eldoc-documentation-function #'ignore))
+ (add-function :before-until (local 'eldoc-documentation-function)
+ #'erldoc-eldoc-function))
(run-hooks 'erlang-mode-hook)
(if (zerop (buffer-size))
(run-hooks 'erlang-new-file-hook)))
diff --git a/lib/tools/emacs/erldoc.el b/lib/tools/emacs/erldoc.el
new file mode 100644
index 0000000000..cb355374d9
--- /dev/null
+++ b/lib/tools/emacs/erldoc.el
@@ -0,0 +1,508 @@
+;;; erldoc.el --- browse Erlang/OTP documentation -*- lexical-binding: t; -*-
+
+;; %CopyrightBegin%
+;;
+;; Copyright Ericsson AB 2016. All Rights Reserved.
+;;
+;; Licensed under the Apache License, Version 2.0 (the "License");
+;; you may not use this file except in compliance with the License.
+;; You may obtain a copy of the License at
+;;
+;; http://www.apache.org/licenses/LICENSE-2.0
+;;
+;; Unless required by applicable law or agreed to in writing, software
+;; distributed under the License is distributed on an "AS IS" BASIS,
+;; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+;; See the License for the specific language governing permissions and
+;; limitations under the License.
+;;
+;; %CopyrightEnd%
+
+;;; Commentary:
+
+;; Crawl Erlang/OTP HTML documentation and generate lookup tables.
+;;
+;; This package depends on `cl-lib', `pcase' and
+;; `libxml-parse-html-region'; emacs 24+ compiled with libxml2 should
+;; work. On emacs 24.1 and 24.2 do `M-x package-install RET cl-lib
+;; RET' to install `cl-lib'.
+;;
+;; Please customise `erldoc-man-index' to point to your local OTP
+;; documentation.
+;;
+;; To use:
+;;
+;; (define-key help-map "u" 'erldoc-browse)
+;; (define-key help-map "t" 'erldoc-browse-topic)
+;; (define-key help-map "a" 'erldoc-apropos)
+;;
+;; Note: these commands trigger indexing OTP documentation on first
+;; run with cache to disk which may take 1-2 minutes.
+
+
+;;; Examples:
+
+;; 1. `M-x erldoc-browse RET erlang:integer_to_binary/2 RET' opens the
+;; `erlang' manual anchored on the entry for `integer_to_binary/2'.
+;;
+;; 2. `M-x erldoc-apropos RET first RET' list all MFAs matching
+;; substring `first'.
+;;
+;; 3. `M-x erldoc-browse-topic RET efficiency_guide#Introduction RET'
+;; opens chapter `Introduction' of the `Efficiency Guide' in the
+;; browser.
+
+;;; History:
+
+;; Written in December 2013 as a temporary solution to help me browse
+;; the rich Erlang/OTP documentation. Three years on I find myself
+;; still using it every day. - Leo (2016)
+
+;;; Code:
+
+(eval-when-compile (require 'url-parse))
+(require 'cl-lib)
+(require 'erlang)
+
+(eval-and-compile ;for emacs < 24.3
+ (or (fboundp 'user-error) (defalias 'user-error 'error)))
+
+(defgroup erldoc nil
+ "Browse Erlang document."
+ :group 'help)
+
+(defcustom erldoc-man-index "http://www.erlang.org/doc/man_index.html"
+ "The URL to the man_index.html page.
+Note it is advisable to customise this to a local URL for example
+`file:///usr/local/19.1/lib/erlang/doc/man_index.html' to speed
+up the indexing."
+ :type 'string
+ :group 'erldoc)
+
+(defcustom erldoc-verify-man-path nil
+ "If non-nil verify man path existence for `file://'."
+ :type 'boolean
+ :group 'erldoc)
+
+(defcustom erldoc-output-file (locate-user-emacs-file "cache/erldoc")
+ "File to store the parsed results."
+ :type 'file
+ :group 'erldoc)
+
+(defun erldoc-strip-string (s)
+ (let* ((re "[ \t\n\r\f\v\u00a0]+")
+ (from (if (string-match (concat "\\`" re) s) (match-end 0) 0))
+ (to (and (string-match (concat re "\\'") s) (match-beginning 0))))
+ (substring s from (and to (max to from)))))
+
+;; Note: don't know how to get the BASE-URL to
+;; `libxml-parse-html-region' to work.
+(defun erldoc-expand-url (url base-url)
+ (if (url-type (url-generic-parse-url url))
+ url
+ (let* ((base (url-generic-parse-url base-url))
+ (dir (directory-file-name (file-name-directory (url-filename base)))))
+ (setf (url-filename base) (expand-file-name url dir))
+ (url-recreate-url base))))
+
+(defun erldoc-parse-html (url)
+ (with-temp-buffer
+ (url-insert-file-contents url)
+ (libxml-parse-html-region (point-min) (point-max))))
+
+(defalias 'erldoc-dom-text-node-p #'stringp)
+
+(defun erldoc-dom-attributes (dom)
+ (and (not (erldoc-dom-text-node-p dom)) (cadr dom)))
+
+(defun erldoc-dom-get-attribute (dom attrib-name)
+ (cdr (assq attrib-name (erldoc-dom-attributes dom))))
+
+(defun erldoc-dom-children (dom)
+ (and (not (erldoc-dom-text-node-p dom)) (cddr dom)))
+
+(defun erldoc-dom-get-text (dom)
+ (let ((text (car (last (erldoc-dom-children dom)))))
+ (and (erldoc-dom-text-node-p text) text)))
+
+(defvar erldoc-dom-walk-parent nil)
+(defvar erldoc-dom-walk-siblings nil)
+
+(defun erldoc-dom-walk (dom k)
+ (funcall k dom)
+ (let ((erldoc-dom-walk-parent dom)
+ (erldoc-dom-walk-siblings (unless (erldoc-dom-text-node-p dom)
+ (cddr dom))))
+ (dolist (child erldoc-dom-walk-siblings)
+ (erldoc-dom-walk child k))))
+
+(defun erldoc-dom-get-element (dom element-name)
+ (catch 'return
+ (erldoc-dom-walk dom (lambda (d)
+ (when (eq (car-safe d) element-name)
+ (throw 'return d))))))
+
+(defun erldoc-dom-get-element-by-id (dom id)
+ (catch 'return
+ (erldoc-dom-walk dom (lambda (d)
+ (when (equal (erldoc-dom-get-attribute d 'id) id)
+ (throw 'return d))))))
+
+(defun erldoc-dom-get-elements-by-id (dom id)
+ (let (result)
+ (erldoc-dom-walk dom (lambda (d)
+ (when (equal (erldoc-dom-get-attribute d 'id) id)
+ (push d result))))
+ (nreverse result)))
+
+(defun erldoc-fix-path (url)
+ (if (and erldoc-verify-man-path
+ ;; Could only verify local files
+ (equal (url-type (url-generic-parse-url url)) "file"))
+ (let* ((obj (url-generic-parse-url url))
+ (new (car (file-expand-wildcards
+ (replace-regexp-in-string
+ "-[0-9]+\\(?:[.][0-9]+\\)*" "*"
+ (url-filename obj))))))
+ (or new (error "File %s does not exist" (url-filename obj)))
+ (setf (url-filename obj) new)
+ (url-recreate-url obj))
+ url))
+
+(defun erldoc-parse-man-index (url)
+ (let ((table (erldoc-dom-get-element (erldoc-parse-html url) 'table))
+ (mans))
+ (erldoc-dom-walk
+ table
+ (lambda (d)
+ (when (eq (car-safe d) 'a)
+ (let ((href (erldoc-dom-get-attribute d 'href)))
+ (when (and href (not (string-match-p "index\\.html\\'" href)))
+ (with-demoted-errors "erldoc-parse-man-index: %S"
+ (push (cons (erldoc-dom-get-text d)
+ (erldoc-fix-path (erldoc-expand-url href url)))
+ mans)))))))
+ (nreverse mans)))
+
+(defun erldoc-parse-man (man)
+ (let ((dom (erldoc-parse-html (cdr man)))
+ (table (make-hash-table :test #'equal)))
+ (erldoc-dom-walk
+ (erldoc-dom-get-element-by-id dom "loadscrollpos")
+ (lambda (d)
+ (let ((href (erldoc-dom-get-attribute d 'href)))
+ (when (and href (string-match "#" href))
+ (puthash (substring href (match-end 0))
+ (list (concat (car man) ":" (erldoc-strip-string
+ (erldoc-dom-get-text d)))
+ (erldoc-expand-url href (cdr man)))
+ table)))))
+ (let ((span-content
+ (lambda (span)
+ (let ((texts))
+ (erldoc-dom-walk span
+ (lambda (d)
+ (and (erldoc-dom-text-node-p d)
+ (push (erldoc-strip-string d) texts))))
+ (and texts (mapconcat 'identity (nreverse texts) " ")))))
+ entries)
+ (erldoc-dom-walk
+ dom
+ (lambda (d)
+ ;; Get the full function signature.
+ (when (and (eq (car-safe d) 'a)
+ (gethash (erldoc-dom-get-attribute d 'name) table))
+ (push (append (gethash (erldoc-dom-get-attribute d 'name) table)
+ (list (funcall span-content
+ (or (erldoc-dom-get-element d 'span)
+ (cadr (memq d erldoc-dom-walk-siblings))))))
+ entries))
+ ;; Get data types
+ (when (and (eq (car-safe d) 'a)
+ (string-prefix-p "type-"
+ (or (erldoc-dom-get-attribute d 'name) "")))
+ (push (list (concat (car man) ":" (funcall span-content d))
+ (concat (cdr man) "#" (erldoc-dom-get-attribute d 'name))
+ (funcall span-content erldoc-dom-walk-parent))
+ entries))))
+ entries)))
+
+(defun erldoc-parse-all (man-index output &optional json)
+ (let* ((output (expand-file-name output))
+ (table (make-hash-table :size 11503 :test #'equal))
+ (mans (erldoc-parse-man-index man-index))
+ (progress 1)
+ (reporter (make-progress-reporter "Parsing Erlang/OTP documentation"
+ progress (length mans)))
+ fails all)
+ (dolist (man mans)
+ (condition-case err
+ (push (erldoc-parse-man man) all)
+ (error (push (error-message-string err) fails)))
+ (accept-process-output nil 0.01)
+ (progress-reporter-update reporter (cl-incf progress)))
+ (when fails
+ (display-warning 'erldoc-parse-all
+ (format "\n\n%s" (mapconcat #'identity fails "\n"))
+ :error))
+ (progress-reporter-done reporter)
+ (mapc (lambda (x) (puthash (car x) (cdr x) table))
+ (apply #'nconc (nreverse all)))
+ (with-temp-buffer
+ (if (not json)
+ (pp table (current-buffer))
+ (eval-and-compile (require 'json))
+ (let ((json-encoding-pretty-print t))
+ (insert (json-encode table))))
+ (unless (file-directory-p (file-name-directory output))
+ (make-directory (file-name-directory output) t))
+ (write-region nil nil output nil nil nil 'ask))))
+
+(defun erldoc-otp-release ()
+ "Get the otp release version (as string) or nil if not found."
+ (let ((otp (erldoc-dom-get-text
+ (erldoc-dom-get-element
+ (erldoc-parse-html
+ (erldoc-expand-url "index.html" erldoc-man-index))
+ 'title))))
+ (and (string-match "[0-9.]+\\'" otp) (match-string 0 otp))))
+
+(defvar erldoc-browse-history nil)
+(defvar erldoc-lookup-table nil)
+
+(defun erldoc-lookup-table ()
+ (or erldoc-lookup-table
+ (progn
+ (unless (file-exists-p erldoc-output-file)
+ (let ((of (pcase (erldoc-otp-release)
+ (`nil erldoc-output-file)
+ (ver (concat erldoc-output-file "-" ver)))))
+ (unless (file-exists-p of)
+ (erldoc-parse-all erldoc-man-index of))
+ (unless (string= erldoc-output-file of)
+ (make-symbolic-link of erldoc-output-file))))
+ (setq erldoc-lookup-table
+ (with-temp-buffer
+ (insert-file-contents erldoc-output-file)
+ (read (current-buffer)))))))
+
+(defun erldoc-best-matches (mfa)
+ (pcase mfa
+ ((and `(,m ,f) (let a (erlang-get-function-arity)))
+ (let ((mfa (format "%s:%s/%s" m f a)))
+ (cond ((gethash mfa (erldoc-lookup-table)) (list mfa))
+ (m (all-completions (concat m ":" f "/") (erldoc-lookup-table)))
+ (t (let* ((mod (erlang-get-module))
+ (mf1 (and mod (concat mod ":" f "/")))
+ (mf2 (concat "erlang:" f "/"))
+ (re (concat ":" (regexp-quote f) "/")))
+ (or (and mf1 (all-completions mf1 (erldoc-lookup-table)))
+ (all-completions mf2 (erldoc-lookup-table))
+ (cl-loop for k being the hash-keys of (erldoc-lookup-table)
+ when (string-match-p re k)
+ collect k)))))))))
+
+;;;###autoload
+(defun erldoc-browse (mfa)
+ (interactive
+ (let ((default
+ ;; `erlang-mode-syntax-table' is lazily initialised.
+ (with-syntax-table (or erlang-mode-syntax-table (standard-syntax-table))
+ (ignore-errors
+ (erldoc-best-matches
+ (or (erlang-get-function-under-point)
+ (save-excursion
+ (goto-char (or (cadr (syntax-ppss)) (point)))
+ (erlang-get-function-under-point))))))))
+ (list (completing-read (format (if default "Function {%d %s} (default %s): "
+ "Function: ")
+ (length default)
+ (if (= (length default) 1) "guess" "guesses")
+ (car default))
+ (erldoc-lookup-table)
+ nil t nil 'erldoc-browse-history default))))
+ (or (stringp mfa)
+ (signal 'wrong-type-argument (list 'string mfa 'mfa)))
+ (browse-url (or (car (gethash mfa (erldoc-lookup-table)))
+ (user-error "No documentation for %s" mfa))))
+
+;;;###autoload
+(defun erldoc-apropos (pattern)
+ (interactive "sPattern: ")
+ (with-help-window (help-buffer)
+ (with-current-buffer standard-output
+ (princ (concat "Erldoc apropos pattern: " pattern "\n\n"))
+ (maphash (lambda (k v)
+ (when (string-match-p pattern k)
+ (insert-text-button k :type 'help-url
+ 'help-args (list (car v)))
+ (insert "\n")))
+ (erldoc-lookup-table)))))
+
+(defun erldoc-tokenize-signature (sig)
+ ;; Divide SIG into (MF ARGLIST RETTYPE)
+ (let ((from (if (string-match "\\`.+?(" sig)
+ (1- (match-end 0))
+ 0))
+ (to (and (string-match "\\s-*->\\s-*.*?\\'" sig) (match-beginning 0))))
+ (list (erldoc-strip-string (substring sig 0 from))
+ (erldoc-strip-string (substring sig from (and to (max from to))))
+ (and to (erldoc-strip-string (substring sig to))))))
+
+(defun erldoc-format-signature (mod fn)
+ (when (and mod fn (or erldoc-lookup-table
+ (file-exists-p erldoc-output-file)))
+ (let ((re (concat "\\`" mod ":" fn "/\\([0-9]+\\)\\'"))
+ (sigs))
+ (maphash (lambda (k v)
+ (when (string-match re k)
+ (push (cons (string-to-number (match-string 1 k))
+ (cdr (erldoc-tokenize-signature (cadr v))))
+ sigs)))
+ (erldoc-lookup-table))
+ (when sigs
+ ;; Mostly single return type but there are exceptions such as
+ ;; `beam_lib:chunks/2,3'.
+ (let ((single-rettype
+ (cl-reduce (lambda (x1 x2) (and x1 x2 (equal x1 x2) x1))
+ sigs :key #'cl-caddr))
+ (sigs (sort sigs #'car-less-than-car)))
+ (if single-rettype
+ (concat mod ":" fn (mapconcat #'cadr sigs " | ") " " single-rettype)
+ (mapconcat (lambda (x) (concat mod ":" fn (nth 1 x) " " (nth 2 x)))
+ sigs "\n")))))))
+
+;;;###autoload
+(defun erldoc-eldoc-function ()
+ "A function suitable for `eldoc-documentation-function'."
+ (save-excursion
+ (pcase (erlang-get-function-under-point)
+ (`(,_ nil) )
+ (`(nil ,fn) (erldoc-format-signature "erlang" fn))
+ (`(,mod ,fn) (erldoc-format-signature mod fn)))))
+
+(defun erldoc-parse-eeps-index ()
+ (let* ((url "http://www.erlang.org/eeps/")
+ (table (catch 'return
+ (erldoc-dom-walk (erldoc-parse-html url)
+ (lambda (d)
+ (and (eq (car-safe d) 'table)
+ (equal (erldoc-dom-get-attribute d 'summary)
+ "Numerical Index of EEPs")
+ (throw 'return d))))))
+ (fix-title (lambda (title)
+ (replace-regexp-in-string
+ "`` *" "" (replace-regexp-in-string " *``, *" " by " title))))
+ (result))
+ (erldoc-dom-walk
+ table (lambda (d)
+ (when (eq (car-safe d) 'a)
+ (push (cons (funcall fix-title (erldoc-dom-get-attribute d 'title))
+ (erldoc-expand-url
+ (erldoc-dom-get-attribute d 'href)
+ url))
+ result))))
+ (nreverse result)))
+
+(defvar erldoc-user-guides nil)
+
+(defvar erldoc-missing-user-guides
+ '("compiler" "hipe" "kernel" "os_mon" "parsetools" "typer")
+ "List of standard Erlang applications with no user guides.")
+
+;; Search in `code:lib_dir/0' using find LIB_DIR -type f -name
+;; '*_app.html'.
+(defvar erldoc-app-manuals '("crypto" "diameter" "erl_docgen"
+ "kernel" "observer" "os_mon"
+ "runtime_tools" "sasl" "snmp"
+ "ssl" "test_server"
+ ("ssh" . "SSH") ("stdlib" . "STDLIB")
+ ("hipe" . "HiPE") ("typer" . "TypEr"))
+ "List of applications that come with a manual.")
+
+(defun erldoc-user-guide-chapters (user-guide)
+ (pcase-let ((`(,name . ,url) user-guide))
+ (unless (member name erldoc-missing-user-guides)
+ (let ((chaps (erldoc-dom-get-elements-by-id
+ (erldoc-dom-get-element-by-id (erldoc-parse-html url) "leftnav")
+ "no")))
+ (or chaps (warn "erldoc-user-guide-chapters no chapters found for `%s'"
+ (cdr user-guide)))
+ (mapcar (lambda (li)
+ (cons (concat name "#" (erldoc-dom-get-attribute li 'title))
+ (erldoc-expand-url (erldoc-dom-get-attribute
+ (erldoc-dom-get-element li 'a) 'href)
+ url)))
+ chaps)))))
+
+(defun erldoc-user-guides-1 ()
+ (let ((url (erldoc-expand-url "applications.html" erldoc-man-index))
+ app-guides app-mans)
+ (erldoc-dom-walk
+ (erldoc-parse-html url)
+ (lambda (d)
+ (when (and (eq (car-safe d) 'a)
+ (not (string-match-p "\\`[0-9.]+\\'" (erldoc-dom-get-text d))))
+ (with-demoted-errors "erldoc-user-guides-1: %S"
+ (let ((name (erldoc-strip-string (erldoc-dom-get-text d)))
+ (index-page (erldoc-fix-path (erldoc-expand-url
+ (erldoc-dom-get-attribute d 'href) url))))
+ (push (cons name (if (member name erldoc-missing-user-guides)
+ index-page
+ (erldoc-expand-url "users_guide.html" index-page)))
+ app-guides)
+ ;; Collect application manuals.
+ (pcase (assoc name (mapcar (lambda (x) (if (consp x) x (cons x x)))
+ erldoc-app-manuals))
+ (`(,_ . ,manual)
+ (push (cons name
+ (erldoc-expand-url (format "%s_app.html" manual)
+ index-page))
+ app-mans))))))))
+ (list (nreverse app-guides)
+ (nreverse app-mans))))
+
+(defun erldoc-user-guides ()
+ (or erldoc-user-guides
+ (let ((file (concat erldoc-output-file "-topics")))
+ (unless (file-exists-p file)
+ (unless (file-directory-p (file-name-directory file))
+ (make-directory (file-name-directory file) t))
+ (with-temp-buffer
+ (pcase-let ((`(,guides ,mans) (erldoc-user-guides-1)))
+ (pp (append (cl-mapcan #'erldoc-user-guide-chapters
+ (append (mapcar
+ (lambda (dir)
+ (cons dir (erldoc-expand-url
+ (concat dir "/users_guide.html")
+ erldoc-man-index)))
+ '("design_principles"
+ "efficiency_guide"
+ "embedded"
+ "getting_started"
+ "installation_guide"
+ "oam"
+ "programming_examples"
+ "reference_manual"
+ "system_architecture_intro"
+ "system_principles"
+ "tutorial"))
+ guides))
+ (mapcar (lambda (man)
+ (pcase-let ((`(,name . ,url) man))
+ (cons (concat name " (App)") url)))
+ mans)
+ (erldoc-parse-eeps-index))
+ (current-buffer)))
+ (write-region nil nil file nil nil nil 'ask)))
+ (setq erldoc-user-guides (with-temp-buffer (insert-file-contents file)
+ (read (current-buffer)))))))
+
+;;;###autoload
+(defun erldoc-browse-topic (topic)
+ (interactive
+ (list (completing-read "User guide: " (erldoc-user-guides) nil t)))
+ (browse-url (cdr (assoc topic (erldoc-user-guides)))))
+
+(provide 'erldoc)
+;;; erldoc.el ends here