On Wed, Mar 13 2024, Ihor Radchenko <yanta...@posteo.net> wrote:
> Pedro Andres Aranda Gutierrez <paag...@gmail.com> writes:
>
>> I really don't have anything to object to the original patch. I support the
>> need to circumvent the "\begin-or-end{frame} inside frame" problem and
>> using orgframe is a clean way of doing so.
>> My only concern is the _default_ value for `org-beamer-frame-environment'.
>> If we set it to "frame", we only need to customise it in the file local
>> variables in files where it needs to be changed and we catch all flies in a
>> stroke:
>>
>> Situation 1: presentation has no "\begin-or-end{frame} inside frame" -> no
>> extra stuff in file local variables AND newenvironment is not generated AND
>> frames are between \begin{frame} and \end{frame}
>> Situation 2: presentation needs to circumvent "\begin-or-end{frame} inside
>> frame" -> set local variable in file AND newenvironment is generated AND
>> frame is changed where it is strictly necessary,
>
> I do not like that users would need to do manual action in situation 2.
> For situation 1, Leo's patch will ensure that all the frames are between
> \begin{frame}..\end{frame}, but newenvironment is still generated.
>
> Leo, may you improve the patch to avoid defining
> `org-beamer-frame-environment' when it is not used in all the frames?
"all the" should be "any of" in that last sentence.
--
How about the attached patch?
The previous org file exports in the same way, and exporting just the
final heading shows that no newenvironment is emitted.
Leo
From 22d829089fc2ca153f1541abe1d5415d311b33d3 Mon Sep 17 00:00:00 2001
From: Leo Butler <leo.but...@umanitoba.ca>
Date: Tue, 12 Mar 2024 15:11:27 -0500
Subject: [PATCH] lisp/ox-beamer.el: constrain use of
org-beamer-frame-environment
* lisp/ox-beamer.el (org-beamer--format-frame, org-beamer-template):
Only use `org-beamer-frame-environment' when a frame is marked as
fragile and the frame's contents include either \begin{frame} or
\end{frame}. When `org-beamer-frame-environment' is used and not
equal to "frame", set `org-beamer--frame-environment-used' to t. When
`org-beamer--frame-environment-used' is t, `org-beamer-template' emits
a definition of the alternative frame environment.
* lisp/ox-beamer.el (org-beamer--frame-environment-used): New
variable.
Refs: https://list.orgmode.org/orgmode/87bk7jeik8.fsf@localhost/
https://list.orgmode.org/87a5nux3zr....@t14.reltub.ca/T/
---
lisp/ox-beamer.el | 26 ++++++++++++++++++++++----
1 file changed, 22 insertions(+), 4 deletions(-)
diff --git a/lisp/ox-beamer.el b/lisp/ox-beamer.el
index 4fad37b59..a79490194 100644
--- a/lisp/ox-beamer.el
+++ b/lisp/ox-beamer.el
@@ -167,6 +167,10 @@ used inside beamer slides."
;;; Internal Variables
+(defvar org-beamer--frame-environment-used nil
+ "Nil unless `org-beamer-frame-environment' is used.
+See `org-beamer--frame-environment'.")
+
(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.")
@@ -429,8 +433,21 @@ used as a communication channel."
;; among `org-beamer-verbatim-elements'.
(org-element-map headline org-beamer-verbatim-elements 'identity
info 'first-match))
- (frame (or (and fragilep org-beamer-frame-environment)
- "frame")))
+ ;; 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 set `org-beamer--frame-environment-used' to
+ ;; t.
+ (frame (let ((selection
+ (or (and fragilep
+ (or (string-search "\\begin{frame}" contents)
+ (string-search "\\end{frame}" contents))
+ org-beamer-frame-environment)
+ "frame")))
+ (unless (string= selection "frame")
+ (setq org-beamer--frame-environment-used t))
+ selection)))
(concat "\\begin{" frame "}"
;; Overlay specification, if any. When surrounded by
;; square brackets, consider it as a default
@@ -851,8 +868,9 @@ holding export options."
(org-latex--insert-compiler info)
;; Document class and packages.
(org-latex-make-preamble info)
- ;; Define the alternative frame environment.
- (unless (equal "frame" org-beamer-frame-environment)
+ ;; Define the alternative frame environment, if needed.
+ (when org-beamer--frame-environment-used
+ (setq org-beamer--frame-environment-used nil)
(format "\\newenvironment<>{%s}[1][]{\\begin{frame}#2[environment=%1$s,#1]}{\\end{frame}}\n"
org-beamer-frame-environment))
;; Insert themes.
--
2.43.0
