;;; ox-beamer.el --- Beamer Backend for Org Export Engine -*- lexical-binding: t; -*- ;; Copyright (C) 2007-2024 Free Software Foundation, Inc. ;; Author: Carsten Dominik ;; Nicolas Goaziou ;; Keywords: org, text, tex ;; This file is part of GNU Emacs. ;; GNU Emacs is free software: you can redistribute it and/or modify ;; it under the terms of the GNU General Public License as published by ;; the Free Software Foundation, either version 3 of the License, or ;; (at your option) any later version. ;; GNU Emacs is distributed in the hope that it will be useful, ;; but WITHOUT ANY WARRANTY; without even the implied warranty of ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ;; GNU General Public License for more details. ;; You should have received a copy of the GNU General Public License ;; along with GNU Emacs. If not, see . ;;; Commentary: ;; ;; This library implements both a Beamer backend, derived from the ;; LaTeX one and a minor mode easing structure edition of the ;; document. See Org manual for more information. ;;; Code: (require 'org-macs) (org-assert-version) (require 'cl-lib) (require 'ox-latex) ;; Install a default set-up for Beamer export. (unless (assoc "beamer" org-latex-classes) (add-to-list 'org-latex-classes '("beamer" "\\documentclass[presentation]{beamer}" ("\\section{%s}" . "\\section*{%s}") ("\\subsection{%s}" . "\\subsection*{%s}") ("\\subsubsection{%s}" . "\\subsubsection*{%s}")))) ;;; User-Configurable Variables (defgroup org-export-beamer nil "Options specific for using the beamer class in LaTeX export." :tag "Org Beamer" :group 'org-export :version "24.2") (defcustom org-beamer-frame-level 1 "The level at which headlines become frames. Headlines at a lower level will be translated into a sectioning structure. At a higher level, they will be translated into blocks. If a headline with a \"BEAMER_env\" property set to \"frame\" is found within a tree, its level locally overrides this number. This variable has no effect on headlines with the \"BEAMER_env\" property set to either \"ignoreheading\", \"appendix\", or \"note\", which will respectively, be invisible, become an appendix or a note. This integer is relative to the minimal level of a headline within the parse tree, defined as 1." :group 'org-export-beamer :type 'integer) (defcustom org-beamer-frame-default-options "" "Default options string to use for frames. For example, it could be set to \"allowframebreaks\"." :group 'org-export-beamer :type '(string :tag "[options]")) (defcustom org-beamer-column-view-format "%45ITEM %10BEAMER_env(Env) %10BEAMER_act(Act) %4BEAMER_col(Col) %8BEAMER_opt(Opt)" "Column view format that should be used to fill the template." :group 'org-export-beamer :version "24.4" :package-version '(Org . "8.0") :type '(choice (const :tag "Do not insert Beamer column view format" nil) (string :tag "Beamer column view format"))) (defcustom org-beamer-theme "default" "Default theme used in Beamer presentations." :group 'org-export-beamer :version "24.4" :package-version '(Org . "8.0") :type '(choice (const :tag "Do not insert a Beamer theme" nil) (string :tag "Beamer theme"))) (defcustom org-beamer-environments-extra nil "Environments triggered by tags in Beamer export. Each entry has 4 elements: name Name of the environment key Selection key for `org-beamer-select-environment' open The opening template for the environment, with the following escapes %a the action/overlay specification %A the default action/overlay specification %R the raw BEAMER_act value %o the options argument, with square brackets %O the raw BEAMER_opt value %h the headline text %r the raw headline text (i.e. without any processing) %H if there is headline text, that raw text in {} braces %U if there is headline text, that raw text in [] brackets %l the label, obtained from `org-beamer--get-label' close The closing string of the environment." :group 'org-export-beamer :package-version '(Org . "9.7") :type '(repeat (list (string :tag "Environment") (string :tag "Selection key") (string :tag "Begin") (string :tag "End")))) (defcustom org-beamer-outline-frame-title "Outline" "Default title of a frame containing an outline." :group 'org-export-beamer :type '(string :tag "Outline frame title")) (defcustom org-beamer-outline-frame-options "" "Outline frame options appended after \\begin{frame}. You might want to put e.g. \"allowframebreaks=0.9\" here." :group 'org-export-beamer :type '(string :tag "Outline frame options")) (defcustom org-beamer-subtitle-format "\\subtitle{%s}" "Format string used for transcoded subtitle. The format string should have at most one \"%s\"-expression, which is replaced with the subtitle." :group 'org-export-beamer :version "26.1" :package-version '(Org . "8.3") :type '(string :tag "Format string")) (defcustom org-beamer-frame-environment "orgframe" "Name of the alternative beamer frame environment. In frames marked as fragile, this environment is used in place of the usual frame environment. This permits insertion of a beamer frame inside example blocks, working around beamer limitations. See https://list.orgmode.org/87a5nux3zr.fsf@t14.reltub.ca/T/#mc7221e93f138bdd56c916b194b9230d3a6c3de09 This option may need to be changed when \"\\end{orgframe}\" string is used inside beamer slides." :group 'org-export-beamer :package-version '(Org . "9.7") :type '(string :tag "Beamer frame") :safe (lambda (str) (string-match-p "^[A-Za-z]+$" str))) ;;; Internal Variables (defconst org-beamer-column-widths "0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 0.0 :ETC" "The column widths that should be installed as allowed property values.") (defconst org-beamer-environments-special '(("againframe" "A") ("appendix" "x") ("column" "c") ("columns" "C") ("frame" "f") ("fullframe" "F") ("ignoreheading" "i") ("note" "n") ("noteNH" "N")) "Alist of environments treated in a special way by the backend. Keys are environment names, as strings, values are bindings used in `org-beamer-select-environment'. Environments listed here, along with their binding, are hard coded and cannot be modified through `org-beamer-environments-extra' variable.") (defconst org-beamer-environments-default '(("block" "b" "\\begin{block}%a{%h}" "\\end{block}") ("alertblock" "a" "\\begin{alertblock}%a{%h}" "\\end{alertblock}") ("verse" "v" "\\begin{verse}%a %% %h" "\\end{verse}") ("quotation" "q" "\\begin{quotation}%a %% %h" "\\end{quotation}") ("quote" "Q" "\\begin{quote}%a %% %h" "\\end{quote}") ("structureenv" "s" "\\begin{structureenv}%a %% %h" "\\end{structureenv}") ("theorem" "t" "\\begin{theorem}%a[%h]%l" "\\end{theorem}") ("definition" "d" "\\begin{definition}%a[%h]%l" "\\end{definition}") ("example" "e" "\\begin{example}%a[%h]%l" "\\end{example}") ("exampleblock" "E" "\\begin{exampleblock}%a{%h}%l" "\\end{exampleblock}") ("proof" "p" "\\begin{proof}%a[%h]" "\\end{proof}") ("beamercolorbox" "o" "\\begin{beamercolorbox}%o{%h}" "\\end{beamercolorbox}") ("onlyenv" "O" "\\begin{onlyenv}%a" "\\end{onlyenv}")) "Environments triggered by properties in Beamer export. These are the defaults - for user definitions, see `org-beamer-environments-extra'.") (defconst org-beamer-verbatim-elements '(code example-block fixed-width inline-src-block src-block verbatim) "List of element or object types producing verbatim text. This is used internally to determine when a frame should have the \"fragile\" option.") ;;; Internal functions (defun org-beamer--normalize-argument (argument type) "Return ARGUMENT string with proper boundaries. TYPE is a symbol among the following: `action' Return ARGUMENT within angular brackets. `defaction' Return ARGUMENT within both square and angular brackets. `option' Return ARGUMENT within square brackets." (if (not (string-match "\\S-" argument)) "" (cl-case type (action (format "<%s>" (org-unbracket-string "<" ">" argument))) (defaction (format "[<%s>]" (org-unbracket-string "<" ">" (org-unbracket-string "[" "]" argument)))) (option (format "[%s]" (org-unbracket-string "[" "]" argument))) (otherwise (error "Invalid `type' argument to `org-beamer--normalize-argument': %s" type))))) (defun org-beamer--element-has-overlay-p (element) "Non-nil when ELEMENT has an overlay specified. An element has an overlay specification when it starts with an `beamer' export-snippet whose value is between angular brackets. Return overlay specification, as a string, or nil." (let ((first-object (car (org-element-contents element)))) (when (org-element-type-p first-object 'export-snippet) (let ((value (org-element-property :value first-object))) (and (string-prefix-p "<" value) (string-suffix-p ">" value) value))))) ;;; Define Backend (org-export-define-derived-backend 'beamer 'latex :menu-entry '(?l 1 ((?B "As LaTeX buffer (Beamer)" org-beamer-export-as-latex) (?b "As LaTeX file (Beamer)" org-beamer-export-to-latex) (?P "As PDF file (Beamer)" org-beamer-export-to-pdf) (?O "As PDF file and open (Beamer)" (lambda (a s v b) (if a (org-beamer-export-to-pdf t s v b) (org-open-file (org-beamer-export-to-pdf nil s v b))))))) :options-alist '((:headline-levels nil "H" org-beamer-frame-level) (:latex-class "LATEX_CLASS" nil "beamer" t) (:beamer-subtitle-format nil nil org-beamer-subtitle-format) (:beamer-column-view-format "COLUMNS" nil org-beamer-column-view-format) (:beamer-theme "BEAMER_THEME" nil org-beamer-theme) (:beamer-color-theme "BEAMER_COLOR_THEME" nil nil t) (:beamer-font-theme "BEAMER_FONT_THEME" nil nil t) (:beamer-inner-theme "BEAMER_INNER_THEME" nil nil t) (:beamer-outer-theme "BEAMER_OUTER_THEME" nil nil t) (:beamer-header "BEAMER_HEADER" nil nil newline) (:beamer-environments-extra nil nil org-beamer-environments-extra) (:beamer-frame-default-options nil nil org-beamer-frame-default-options) (:beamer-outline-frame-options nil nil org-beamer-outline-frame-options) (:beamer-outline-frame-title nil nil org-beamer-outline-frame-title)) :translate-alist '((bold . org-beamer-bold) (export-block . org-beamer-export-block) (export-snippet . org-beamer-export-snippet) (headline . org-beamer-headline) (item . org-beamer-item) (keyword . org-beamer-keyword) (link . org-beamer-link) (plain-list . org-beamer-plain-list) (radio-target . org-beamer-radio-target) (template . org-beamer-template))) ;;; Transcode Functions ;;;; Bold (defun org-beamer-bold (bold contents _info) "Transcode BOLD object into Beamer code. CONTENTS is the text being bold. INFO is a plist used as a communication channel." (format "\\alert%s{%s}" (or (org-beamer--element-has-overlay-p bold) "") contents)) ;;;; Export Block (defun org-beamer-export-block (export-block _contents _info) "Transcode an EXPORT-BLOCK element into Beamer code. CONTENTS is nil. INFO is a plist used as a communication channel." (when (member (org-element-property :type export-block) '("BEAMER" "LATEX")) (org-remove-indentation (org-element-property :value export-block)))) ;;;; Export Snippet (defun org-beamer-export-snippet (export-snippet _contents info) "Transcode an EXPORT-SNIPPET object into Beamer code. CONTENTS is nil. INFO is a plist used as a communication channel." (let ((backend (org-export-snippet-backend export-snippet)) (value (org-element-property :value export-snippet))) ;; Only "latex" and "beamer" snippets are retained. (cond ((eq backend 'latex) value) ;; Ignore "beamer" snippets specifying overlays. ((and (eq backend 'beamer) (or (org-export-get-previous-element export-snippet info) (not (string-match "\\`<.*>\\'" value)))) value)))) ;;;; Headline ;; ;; The main function to translate a headline is ;; `org-beamer-headline'. ;; ;; Depending on the level at which a headline is considered as ;; a frame (given by `org-beamer--frame-level'), the headline is ;; either a section (`org-beamer--format-section'), a frame ;; (`org-beamer--format-frame') or a block ;; (`org-beamer--format-block'). ;; ;; `org-beamer-headline' also takes care of special environments ;; like "ignoreheading", "note", "noteNH", "appendix" and ;; "againframe". (defun org-beamer--get-label (headline info) "Return label for HEADLINE, as a string. INFO is a plist used as a communication channel. The value is either the label specified in \"BEAMER_opt\" property, the custom ID, if there is one and `:latex-prefer-user-labels' property has a non-nil value, or a unique internal label. This function assumes HEADLINE will be treated as a frame." (cond ((let ((opt (org-element-property :BEAMER_OPT headline))) (and (stringp opt) (string-match "\\(?:^\\|,\\)label=\\(.*?\\)\\(?:$\\|,\\)" opt) (let ((label (match-string 1 opt))) (if (string-match-p "\\`{.*}\\'" label) (substring label 1 -1) label))))) ((and (plist-get info :latex-prefer-user-labels) (org-element-property :CUSTOM_ID headline))) (t (format "sec:%s" (org-export-get-reference headline info))))) (defun org-beamer--frame-level (headline info) "Return frame level in subtree containing HEADLINE. INFO is a plist used as a communication channel." (or ;; 1. Look for "frame" environment in parents, starting from the ;; farthest. (catch 'exit (dolist (parent (nreverse (org-element-lineage headline))) (let ((env (org-element-property :BEAMER_ENV parent))) (when (and env (member-ignore-case env '("frame" "fullframe"))) (throw 'exit (org-export-get-relative-level parent info)))))) ;; 2. Look for "frame" environment in HEADLINE. (let ((env (org-element-property :BEAMER_ENV headline))) (and env (member-ignore-case env '("frame" "fullframe")) (org-export-get-relative-level headline info))) ;; 3. Look for "frame" environment in sub-tree. (org-element-map headline 'headline (lambda (hl) (let ((env (org-element-property :BEAMER_ENV hl))) (when (and env (member-ignore-case env '("frame" "fullframe"))) (org-export-get-relative-level hl info)))) info 'first-match) ;; 4. No "frame" environment in tree: use default value. (plist-get info :headline-levels))) (defun org-beamer--format-section (headline contents info) "Format HEADLINE as a sectioning part. CONTENTS holds the contents of the headline. INFO is a plist used as a communication channel." (let ((latex-headline (org-export-with-backend ;; We create a temporary export backend which behaves the ;; same as current one, but adds "\protect" in front of the ;; output of some objects. (org-export-create-backend :parent 'latex :transcoders (let ((protected-output (lambda (object contents info) (let ((code (org-export-with-backend 'beamer object contents info))) (if (org-string-nw-p code) (concat "\\protect" code) code))))) (mapcar (lambda (type) (cons type protected-output)) '(bold footnote-reference italic strike-through timestamp underline)))) headline contents info)) (mode-specs (org-element-property :BEAMER_ACT headline))) (if (and mode-specs (string-match "\\`\\\\\\(.*?\\)\\(?:\\*\\|\\[.*\\]\\)?{" latex-headline)) ;; Insert overlay specifications. (replace-match (concat (match-string 1 latex-headline) (format "<%s>" mode-specs)) nil nil latex-headline 1) latex-headline))) (defun org-beamer--format-frame (headline contents info) "Format HEADLINE as a frame. CONTENTS holds the contents of the headline. INFO is a plist used as a communication channel." (let* ((fragilep ;; FRAGILEP is non-nil when HEADLINE contains an element ;; among `org-beamer-verbatim-elements'. (org-element-map headline org-beamer-verbatim-elements 'identity info 'first-match)) ;; If FRAGILEP is non-nil and CONTENTS contains an occurrence ;; of \begin{frame} or \end{frame}, then set the FRAME ;; environment to be `org-beamer-frame-environment'; ;; otherwise, use "frame". If the selected environment is not ;; "frame", then add the property :beamer-define-frame to ;; INFO and set it to t. (frame (let ((selection (or (and fragilep (or (string-match-p "\\\\begin{frame}" contents) (string-match-p "\\\\end{frame}" contents)) org-beamer-frame-environment) "frame"))) (unless (string= selection "frame") (setq info (plist-put info :beamer-define-frame t))) selection))) (concat "\\begin{" frame "}" ;; Overlay specification, if any. When surrounded by ;; square brackets, consider it as a default ;; specification. (let ((action (org-element-property :BEAMER_ACT headline))) (cond ((not action) "") ((string-match "\\`\\[.*\\]\\'" action ) (org-beamer--normalize-argument action 'defaction)) (t (org-beamer--normalize-argument action 'action)))) ;; Options, if any. (let* ((beamer-opt (org-element-property :BEAMER_OPT headline)) (options ;; Collect nonempty options from default value and ;; headline's properties. (cl-remove-if-not #'org-string-nw-p (append (org-split-string (plist-get info :beamer-frame-default-options) ",") (and beamer-opt (org-split-string ;; Remove square brackets if user provided ;; them. (and (string-match "^\\[?\\(.*\\)\\]?$" beamer-opt) (match-string 1 beamer-opt)) ","))))) (fragile ;; Add "fragile" option if necessary. (and fragilep (not (member "fragile" options)) (list "fragile"))) (label ;; Provide an automatic label for the frame unless ;; the user specified one. Also refrain from ;; labeling `allowframebreaks' frames; this is not ;; allowed by Beamer. (and (not (member "allowframebreaks" options)) (not (cl-some (lambda (s) (string-match-p "^label=" s)) options)) (list (let ((label (org-beamer--get-label headline info))) ;; Labels containing colons need to be ;; wrapped within braces. (format (if (string-match-p ":" label) "label={%s}" "label=%s") label)))))) ;; Change options list into a string. (org-beamer--normalize-argument (mapconcat #'identity (append label fragile options) ",") 'option)) ;; Title. (let ((env (org-element-property :BEAMER_ENV headline))) (format "{%s}" (if (and env (equal (downcase env) "fullframe")) "" (org-export-data (org-element-property :title headline) info)))) ;; Subtitle (when-let* ((subtitle (org-element-property :BEAMER_SUBTITLE headline))) (format "{%s}" (org-export-data (org-element-parse-secondary-string subtitle (org-element-restriction 'keyword)) info))) "\n" ;; The following workaround is required in fragile frames ;; as Beamer will append "\par" to the beginning of the ;; contents. So we need to make sure the command is ;; separated from the contents by at least one space. If ;; it isn't, it will create "\parfirst-word" command and ;; remove the first word from the contents in the PDF ;; output. (if (not fragilep) contents (replace-regexp-in-string "\\`\n*" "\\& " (or contents ""))) "\\end{" frame "}"))) (defun org-beamer--format-block (headline contents info) "Format HEADLINE as a block. CONTENTS holds the contents of the headline. INFO is a plist used as a communication channel." (let* ((column-width (org-element-property :BEAMER_COL headline)) ;; ENVIRONMENT defaults to "block" if none is specified and ;; there is no column specification. If there is a column ;; specified but still no explicit environment, ENVIRONMENT ;; is "column". (environment (let ((env (org-element-property :BEAMER_ENV headline))) (cond ;; "block" is the fallback environment. ((and (not env) (not column-width)) "block") ;; "column" only. ((not env) "column") ;; Use specified environment. (t env)))) (raw-title (org-element-property :raw-value headline)) (env-format (cond ((member environment '("column" "columns")) nil) ((assoc environment (append (plist-get info :beamer-environments-extra) org-beamer-environments-default))) (t (user-error "Wrong block type at a headline named \"%s\"" raw-title)))) (title (org-export-data (org-element-property :title headline) info)) (raw-options (org-element-property :BEAMER_OPT headline)) (options (if raw-options (org-beamer--normalize-argument raw-options 'option) "")) ;; also process actions (raw-action (org-element-property :BEAMER_ACT headline)) (action (if raw-action ;; If BEAMER_act property has its value enclosed in square ;; brackets, it is a default overlay specification and ;; overlay specification is empty. Otherwise, it is an ;; overlay specification and the default one is nil. (org-beamer--normalize-argument raw-action (if (string-match "\\`\\[.*\\]\\'" raw-action) 'defaction 'action)) "")) ;; Start a "columns" environment when explicitly requested or ;; when there is no previous headline or the previous ;; headline do not have a BEAMER_column property. (parent-env (org-element-property :BEAMER_ENV (org-element-lineage headline 'headline))) (start-columns-p (or (equal environment "columns") (and column-width (not (and parent-env (equal (downcase parent-env) "columns"))) (or (org-export-first-sibling-p headline info) (not (org-element-property :BEAMER_COL (org-export-get-previous-element headline info))))))) ;; End the "columns" environment when explicitly requested or ;; when there is no next headline or the next headline do not ;; have a BEAMER_column property. (end-columns-p (or (equal environment "columns") (and column-width (not (and parent-env (equal (downcase parent-env) "columns"))) (or (org-export-last-sibling-p headline info) (not (org-element-property :BEAMER_COL (org-export-get-next-element headline info)))))))) (concat (when start-columns-p ;; Column can accept options only when the environment is ;; explicitly defined. (if (not (equal environment "columns")) "\\begin{columns}\n" (format "\\begin{columns}%s\n" options))) (when column-width (format "\\begin{column}%s%s{%s}\n" ;; One can specify placement for column only when ;; HEADLINE stands for a column on its own. options (if env-format "" ; Inner environment is specified - pass actions later. action) (format "%s\\columnwidth" column-width))) ;; Block's opening string. (when (nth 2 env-format) (concat (org-fill-template (nth 2 env-format) (nconc (cond ((not action) (list (cons "a" "") (cons "A" "") (cons "R" ""))) ((and (string-prefix-p "[" action) (string-suffix-p "]" action)) (list (cons "A" (org-beamer--normalize-argument action 'defaction)) (cons "a" "") (cons "R" raw-action))) (t (list (cons "a" action) (cons "A" "") (cons "R" raw-action)))) (list (cons "o" options) (cons "O" (or raw-options "")) (cons "h" title) (cons "r" raw-title) (cons "l" (format "\\label{%s}" (org-beamer--get-label headline info))) (cons "H" (if (equal raw-title "") "" (format "{%s}" raw-title))) (cons "U" (if (equal raw-title "") "" (format "[%s]" raw-title)))))) "\n")) contents ;; Block's closing string, if any. (and (nth 3 env-format) (concat (nth 3 env-format) "\n")) (when column-width "\\end{column}\n") (when end-columns-p "\\end{columns}")))) (defun org-beamer-headline (headline contents info) "Transcode HEADLINE element into Beamer code. CONTENTS is the contents of the headline. INFO is a plist used as a communication channel." (unless (org-element-property :footnote-section-p headline) (let ((level (org-export-get-relative-level headline info)) (frame-level (org-beamer--frame-level headline info)) (environment (let ((env (org-element-property :BEAMER_ENV headline))) (or (org-string-nw-p env) "block")))) (cond ;; Case 1: Resume frame specified by "BEAMER_ref" property. ((equal environment "againframe") (let ((ref (org-element-property :BEAMER_REF headline))) ;; Reference to frame being resumed is mandatory. Ignore ;; the whole headline if it isn't provided. (when (org-string-nw-p ref) (concat "\\againframe" ;; Overlay specification. (let ((overlay (org-element-property :BEAMER_ACT headline))) (when overlay (org-beamer--normalize-argument overlay (if (string-match "\\`\\[.*\\]\\'" overlay) 'defaction 'action)))) ;; Options. (let ((options (org-element-property :BEAMER_OPT headline))) (when options (org-beamer--normalize-argument options 'option))) ;; Resolve reference provided by "BEAMER_ref" ;; property. This is done by building a minimal ;; fake link and calling the appropriate resolve ;; function, depending on the reference syntax. (let ((target (if (string-match "\\`\\(id:\\|#\\)" ref) (org-export-resolve-id-link `(link (:path ,(substring ref (match-end 0)))) info) (org-export-resolve-fuzzy-link `(link (:path ;; Look for headlines only. ,(if (eq (string-to-char ref) ?*) ref (concat "*" ref)))) info)))) ;; Now use user-defined label provided in TARGET ;; headline, or fallback to standard one. (format "{%s}" (org-beamer--get-label target info))))))) ;; Case 2: Creation of an appendix is requested. ((equal environment "appendix") (concat "\\appendix" (org-element-property :BEAMER_ACT headline) "\n" (make-string (org-element-property :pre-blank headline) ?\n) contents)) ;; Case 3: Ignore heading. ((equal environment "ignoreheading") (concat (make-string (org-element-property :pre-blank headline) ?\n) contents)) ;; Case 4: HEADLINE is a note. ((member environment '("note" "noteNH")) (concat "\\note" ;; Overlay specification. (let ((overlay (org-element-property :BEAMER_ACT headline))) (when overlay (org-beamer--normalize-argument overlay (if (string-match "\\`\\[.*\\]\\'" overlay) 'defaction 'action)))) (format "{%s}" (concat (and (equal environment "note") (concat (org-export-data (org-element-property :title headline) info) "\n")) (org-trim contents))))) ;; Case 5: HEADLINE is a frame. ((= level frame-level) (org-beamer--format-frame headline contents info)) ;; Case 6: Regular section, extracted from ;; `org-latex-classes'. ((< level frame-level) (org-beamer--format-section headline contents info)) ;; Case 7: Otherwise, HEADLINE is a block. (t (org-beamer--format-block headline contents info)))))) ;;;; Item (defun org-beamer-item (item contents info) "Transcode an ITEM element into Beamer code. CONTENTS holds the contents of the item. INFO is a plist holding contextual information." (org-export-with-backend ;; Delegate item export to `latex'. However, we use `beamer' ;; transcoders for objects in the description tag. (org-export-create-backend :parent 'beamer :transcoders (list (cons 'item (lambda (item _c _i) (let ((action (let ((first (car (org-element-contents item)))) (and (org-element-type-p first 'paragraph) (org-beamer--element-has-overlay-p first)))) (output (org-latex-item item contents info))) (if (not (and action (string-match "\\\\item" output))) output ;; If the item starts with a paragraph and that paragraph ;; starts with an export snippet specifying an overlay, ;; append it to the \item command. (replace-match (concat "\\\\item" action) nil nil output))))))) item contents info)) ;;;; Keyword (defun org-beamer-keyword (keyword contents info) "Transcode a KEYWORD element into Beamer code. CONTENTS is nil. INFO is a plist used as a communication channel." (let ((key (org-element-property :key keyword)) (value (org-element-property :value keyword))) ;; Handle specifically BEAMER and TOC (headlines only) keywords. ;; Otherwise, fallback to `latex' backend. (cond ((equal key "BEAMER") value) ((and (equal key "TOC") (string-match "\\" value)) (let ((depth (or (and (string-match "[0-9]+" value) (string-to-number (match-string 0 value))) (plist-get info :with-toc))) (options (and (string-match "\\[.*?\\]" value) (match-string 0 value)))) (concat (when (wholenump depth) (format "\\setcounter{tocdepth}{%s}\n" depth)) "\\tableofcontents" options))) (t (org-export-with-backend 'latex keyword contents info))))) ;;;; Link (defun org-beamer-link (link contents info) "Transcode a LINK object into Beamer code. CONTENTS is the description part of the link. INFO is a plist used as a communication channel." (or (org-export-custom-protocol-maybe link contents 'beamer info) ;; Fall-back to LaTeX export. However, prefer "\hyperlink" over ;; "\hyperref" since the former handles overlay specifications. (let* ((latex-link (org-export-with-backend 'latex link contents info)) (parent (org-element-parent-element link)) (attr (org-export-read-attribute :attr_beamer parent)) (overlay (plist-get attr :overlay))) (cond ((string-match "\\`\\\\hyperref\\[\\(.*?\\)\\]" latex-link) (replace-match (format "\\\\hyperlink%s{\\1}" (or (org-beamer--element-has-overlay-p link) "")) nil nil latex-link)) ((string-match "\\\\include\\(graphics\\|svg\\)\\([[{]?\\)" latex-link) ;; Check for overlay specification and insert if ;; present. (replace-match (format "\\\\include\\1%s\\2" (if overlay overlay "")) nil nil latex-link)) (t latex-link))))) ;;;; Plain List ;; ;; Plain lists support `:environment', `:overlay' and `:options' ;; attributes. (defun org-beamer-plain-list (plain-list contents info) "Transcode a PLAIN-LIST element into Beamer code. CONTENTS is the contents of the list. INFO is a plist holding contextual information." (let* ((type (org-element-property :type plain-list)) (attributes (org-combine-plists (org-export-read-attribute :attr_latex plain-list) (org-export-read-attribute :attr_beamer plain-list))) (latex-type (let ((env (plist-get attributes :environment))) (cond (env) ((eq type 'ordered) "enumerate") ((eq type 'descriptive) "description") (t "itemize"))))) (org-latex--wrap-label plain-list (format "\\begin{%s}%s%s\n%s\\end{%s}" latex-type ;; Default overlay specification, if any. (org-beamer--normalize-argument (or (plist-get attributes :overlay) "") 'defaction) ;; Second optional argument depends on the list type. (org-beamer--normalize-argument (or (plist-get attributes :options) "") 'option) ;; Eventually insert contents and close environment. contents latex-type) info))) ;;;; Radio Target (defun org-beamer-radio-target (radio-target text info) "Transcode a RADIO-TARGET object into Beamer code. TEXT is the text of the target. INFO is a plist holding contextual information." (format "\\hypertarget%s{%s}{%s}" (or (org-beamer--element-has-overlay-p radio-target) "") (org-export-get-reference radio-target info) text)) ;;;; Template ;; ;; Template used is similar to the one used in `latex' backend, ;; excepted for the table of contents and Beamer themes. (defun org-beamer-template (contents info) "Return complete document string after Beamer conversion. CONTENTS is the transcoded contents string. INFO is a plist holding export options." (let ((title (org-export-data (plist-get info :title) info)) (subtitle (org-export-data (plist-get info :subtitle) info))) (concat ;; Timestamp. (and (plist-get info :time-stamp-file) (format-time-string "%% Created %Y-%m-%d %a %H:%M\n")) ;; LaTeX compiler (org-latex--insert-compiler info) ;; Document class and packages. (org-latex-make-preamble info) ;; Define the alternative frame environment, if needed. (when (plist-get info :beamer-define-frame) (format "\\newenvironment<>{%s}[1][]{\\begin{frame}#2[environment=%1$s,#1]}{\\end{frame}}\n" org-beamer-frame-environment)) ;; Insert themes. (let ((format-theme (lambda (prop command) (let ((theme (plist-get info prop))) (when theme (concat command (if (not (string-match "\\[.*\\]" theme)) (format "{%s}\n" theme) (format "%s{%s}\n" (match-string 0 theme) (org-trim (replace-match "" nil nil theme)))))))))) (mapconcat (lambda (args) (apply format-theme args)) '((:beamer-theme "\\usetheme") (:beamer-color-theme "\\usecolortheme") (:beamer-font-theme "\\usefonttheme") (:beamer-inner-theme "\\useinnertheme") (:beamer-outer-theme "\\useoutertheme")) "")) ;; Possibly limit depth for headline numbering. (let ((sec-num (plist-get info :section-numbers))) (when (integerp sec-num) (format "\\setcounter{secnumdepth}{%d}\n" sec-num))) ;; Author. (let ((author (and (plist-get info :with-author) (let ((auth (plist-get info :author))) (and auth (org-export-data auth info))))) (email (and (plist-get info :with-email) (org-export-data (plist-get info :email) info)))) (cond ((and author email (not (string= "" email))) (format "\\author{%s\\thanks{%s}}\n" author email)) ((or author email) (format "\\author{%s}\n" (or author email))))) ;; Date. (let ((date (and (plist-get info :with-date) (org-export-get-date info)))) (format "\\date{%s}\n" (org-export-data date info))) ;; Title (format "\\title{%s}\n" title) (when (org-string-nw-p subtitle) (concat (format (plist-get info :beamer-subtitle-format) subtitle) "\n")) ;; Beamer-header (let ((beamer-header (plist-get info :beamer-header))) (when beamer-header (format "%s\n" (plist-get info :beamer-header)))) ;; 9. Hyperref options. (let ((template (plist-get info :latex-hyperref-template))) (and (stringp template) (format-spec template (org-latex--format-spec info)))) ;; engrave-faces-latex preamble (when (and (eq (plist-get info :latex-src-block-backend) 'engraved) (org-element-map (plist-get info :parse-tree) '(src-block inline-src-block) #'identity info t)) (org-latex-generate-engraved-preamble info)) ;; Document start. "\\begin{document}\n\n" ;; Title command. (org-element-normalize-string (cond ((not (plist-get info :with-title)) nil) ((string= "" title) nil) ((not (stringp org-latex-title-command)) nil) ((string-match "\\(?:[^%]\\|^\\)%s" org-latex-title-command) (format org-latex-title-command title)) (t org-latex-title-command))) ;; Table of contents. (let ((depth (plist-get info :with-toc))) (when depth (concat (format "\\begin{frame}%s{%s}\n" (org-beamer--normalize-argument (plist-get info :beamer-outline-frame-options) 'option) (plist-get info :beamer-outline-frame-title)) (when (wholenump depth) (format "\\setcounter{tocdepth}{%d}\n" depth)) "\\tableofcontents\n" "\\end{frame}\n\n"))) ;; Document's body. contents ;; Creator. (if (plist-get info :with-creator) (concat (plist-get info :creator) "\n") "") ;; Document end. "\\end{document}"))) ;;; Minor Mode (defvar org-beamer-mode-map (let ((map (make-sparse-keymap))) (define-key map "\C-c\C-b" 'org-beamer-select-environment) map) "The keymap for `org-beamer-mode'.") ;;;###autoload (define-minor-mode org-beamer-mode "Support for editing Beamer oriented Org mode files." :lighter " Bm") (font-lock-add-keywords 'org-mode '((":\\(B_[a-z]+\\|BMCOL\\):" 1 'org-beamer-tag prepend)) 'prepend) (defface org-beamer-tag '((t (:box (:line-width 1 :color "grey40")))) "The special face for beamer tags." :group 'org-export-beamer) (defun org-beamer-property-changed (property value) "Track the BEAMER_env property with tags. PROPERTY is the name of the modified property. VALUE is its new value." (cond ((equal property "BEAMER_env") (save-excursion (org-back-to-heading t) ;; Filter out Beamer-related tags and install environment tag. (let ((tags (cl-remove-if (lambda (x) (string-match "^B_" x)) (org-get-tags nil t))) (env-tag (and (org-string-nw-p value) (concat "B_" value)))) (org-set-tags (if env-tag (cons env-tag tags) tags)) (when env-tag (org-toggle-tag env-tag 'on))))) ((equal property "BEAMER_col") (org-toggle-tag "BMCOL" (if (org-string-nw-p value) 'on 'off))))) (add-hook 'org-property-changed-functions 'org-beamer-property-changed) (defun org-beamer-allowed-property-values (property) "Supply allowed values for PROPERTY." (cond ((and (equal property "BEAMER_env") (not (org-entry-get nil (concat property "_ALL") 'inherit))) ;; If no allowed values for BEAMER_env have been defined, ;; supply all defined environments (mapcar 'car (append org-beamer-environments-special org-beamer-environments-extra org-beamer-environments-default))) ((and (equal property "BEAMER_col") (not (org-entry-get nil (concat property "_ALL") 'inherit))) ;; If no allowed values for BEAMER_col have been defined, supply ;; some. (split-string org-beamer-column-widths " ")))) (add-hook 'org-property-allowed-value-functions 'org-beamer-allowed-property-values) ;;; Commands ;;;###autoload (defun org-beamer-export-as-latex (&optional async subtreep visible-only body-only ext-plist) "Export current buffer as a Beamer buffer. If narrowing is active in the current buffer, only export its narrowed part. If a region is active, export that region. A non-nil optional argument ASYNC means the process should happen asynchronously. The resulting buffer should be accessible through the `org-export-stack' interface. When optional argument SUBTREEP is non-nil, export the sub-tree at point, extracting information from the headline properties first. When optional argument VISIBLE-ONLY is non-nil, don't export contents of hidden elements. When optional argument BODY-ONLY is non-nil, only write code between \"\\begin{document}\" and \"\\end{document}\". EXT-PLIST, when provided, is a property list with external parameters overriding Org default settings, but still inferior to file-local settings. Export is done in a buffer named \"*Org BEAMER Export*\", which will be displayed when `org-export-show-temporary-export-buffer' is non-nil." (interactive) (org-export-to-buffer 'beamer "*Org BEAMER Export*" async subtreep visible-only body-only ext-plist (if (fboundp 'major-mode-remap) (major-mode-remap 'latex-mode) #'LaTeX-mode))) ;;;###autoload (defun org-beamer-export-to-latex (&optional async subtreep visible-only body-only ext-plist) "Export current buffer as a Beamer presentation (tex). If narrowing is active in the current buffer, only export its narrowed part. If a region is active, export that region. A non-nil optional argument ASYNC means the process should happen asynchronously. The resulting file should be accessible through the `org-export-stack' interface. When optional argument SUBTREEP is non-nil, export the sub-tree at point, extracting information from the headline properties first. When optional argument VISIBLE-ONLY is non-nil, don't export contents of hidden elements. When optional argument BODY-ONLY is non-nil, only write code between \"\\begin{document}\" and \"\\end{document}\". EXT-PLIST, when provided, is a property list with external parameters overriding Org default settings, but still inferior to file-local settings. Return output file's name." (interactive) (let ((file (org-export-output-file-name ".tex" subtreep))) (org-export-to-file 'beamer file async subtreep visible-only body-only ext-plist))) ;;;###autoload (defun org-beamer-export-to-pdf (&optional async subtreep visible-only body-only ext-plist) "Export current buffer as a Beamer presentation (PDF). If narrowing is active in the current buffer, only export its narrowed part. If a region is active, export that region. A non-nil optional argument ASYNC means the process should happen asynchronously. The resulting file should be accessible through the `org-export-stack' interface. When optional argument SUBTREEP is non-nil, export the sub-tree at point, extracting information from the headline properties first. When optional argument VISIBLE-ONLY is non-nil, don't export contents of hidden elements. When optional argument BODY-ONLY is non-nil, only write code between \"\\begin{document}\" and \"\\end{document}\". EXT-PLIST, when provided, is a property list with external parameters overriding Org default settings, but still inferior to file-local settings. Return PDF file's name." (interactive) (let ((file (org-export-output-file-name ".tex" subtreep))) (org-export-to-file 'beamer file async subtreep visible-only body-only ext-plist #'org-latex-compile))) ;;;###autoload (defun org-beamer-select-environment () "Select the environment to be used by beamer for this entry. While this uses (for convenience) a tag selection interface, the result of this command will be that the BEAMER_env *property* of the entry is set. In addition to this, the command will also set a tag as a visual aid, but the tag does not have any semantic meaning." (interactive) ;; Make sure `org-beamer-environments-special' has a higher ;; priority than `org-beamer-environments-extra'. (let* ((envs (append org-beamer-environments-special org-beamer-environments-extra org-beamer-environments-default)) (org-current-tag-alist (append '((:startgroup)) (mapcar (lambda (e) (cons (concat "B_" (car e)) (string-to-char (nth 1 e)))) envs) '((:endgroup)) '(("BMCOL" . ?|)))) (org-tag-persistent-alist nil) (org-use-fast-tag-selection t) (org-fast-tag-selection-single-key t)) (org-set-tags-command) (let ((tags (org-get-tags nil t))) (cond ;; For a column, automatically ask for its width. ((eq org-last-tag-selection-key ?|) (if (member "BMCOL" tags) (org-set-property "BEAMER_col" (read-string "Column width: ")) (org-delete-property "BEAMER_col"))) ;; For an "againframe" section, automatically ask for reference ;; to resumed frame and overlay specifications. ((eq org-last-tag-selection-key ?A) (if (equal (org-entry-get nil "BEAMER_env") "againframe") (progn (org-entry-delete nil "BEAMER_env") (org-entry-delete nil "BEAMER_ref") (org-entry-delete nil "BEAMER_act")) (org-entry-put nil "BEAMER_env" "againframe") (org-set-property "BEAMER_ref" (read-string "Frame reference (*Title, #custom-id, id:...): ")) (org-set-property "BEAMER_act" (read-string "Overlay specification: ")))) ((let* ((tags-re (concat "B_" (regexp-opt (mapcar #'car envs) t))) (env (cl-some (lambda (tag) (and (string-match tags-re tag) (match-string 1 tag))) tags))) (and env (progn (org-entry-put nil "BEAMER_env" env) t)))) (t (org-entry-delete nil "BEAMER_env")))))) ;;;###autoload (defun org-beamer-publish-to-latex (plist filename pub-dir) "Publish an Org file to a Beamer presentation (LaTeX). FILENAME is the filename of the Org file to be published. PLIST is the property list for the given project. PUB-DIR is the publishing directory. Return output file name." (org-publish-org-to 'beamer filename ".tex" plist pub-dir)) ;;;###autoload (defun org-beamer-publish-to-pdf (plist filename pub-dir) "Publish an Org file to a Beamer presentation (PDF, via LaTeX). FILENAME is the filename of the Org file to be published. PLIST is the property list for the given project. PUB-DIR is the publishing directory. Return output file name." ;; Unlike to `org-beamer-publish-to-latex', PDF file is generated in ;; working directory and then moved to publishing directory. (org-publish-attachment plist ;; Default directory could be anywhere when this function is ;; called. We ensure it is set to source file directory during ;; compilation so as to not break links to external documents. (let ((default-directory (file-name-directory filename))) (org-latex-compile (org-publish-org-to 'beamer filename ".tex" plist (file-name-directory filename)))) pub-dir)) (provide 'ox-beamer) ;; Local variables: ;; generated-autoload-file: "org-loaddefs.el" ;; End: ;;; ox-beamer.el ends here