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;;; eev-codings.el -- tricks to support both the UTF8 coding system and unibyte ;; Copyright (C) 2018-2019 Free Software Foundation, Inc. ;; ;; This file is part of GNU eev. ;; ;; GNU eev 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 eev 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 <http://www.gnu.org/licenses/>. ;; ;; Author: Eduardo Ochs <firstname.lastname@example.org> ;; Maintainer: Eduardo Ochs <email@example.com> ;; Version: 20190304 ;; Keywords: e-scripts ;; ;; Latest version: <http://angg.twu.net/eev-current/eev-coding.el> ;; htmlized: <http://angg.twu.net/eev-current/eev-coding.el.html> ;; See also: <http://angg.twu.net/eev-intros/find-eev-intro.html> ;;; Commentary: ;; Until mid-2017 a user who wanted to use anchors (like "«tag»") in ;; both unibyte and multibyte buffers had to put something like this ;; ;; ee-anchor-format: "«%s»" ;; ;; in the local variables section at the end of (at least some) of his ;; files; the functions defined here make the local variables section ;; trick unnecessary - `ee-format-as-anchor' now uses `ee-tolatin1' to ;; produce a search string that works both unibyte, on UTF-8, on ;; latin-1 files and some (most of?) other encodings. ;; ;; NOTE: `ee-tolatin1' a hack! Conversion to latin-1 seems to work in ;; most cases, but I don't understand very well the reasons why... I ;; have some notes about all this in these e-script blocks in my notes ;; about Emacs: ;; ;; (find-es "emacs" "unibyte-2019") ;; (find-es "emacs" "unibyte-2019-search") ;; (find-es "emacs" "creating-utf8-files") ;; (find-es "emacs" "ee-re-to") ;; http://angg.twu.net/e/emacs.e.html#unibyte-2019 ;; http://angg.twu.net/e/emacs.e.html#unibyte-2019-search ;; http://angg.twu.net/e/emacs.e.html#creating-utf8-files ;; http://angg.twu.net/e/emacs.e.html#ee-re-to ;; ;; ;; NOTE 2: Sorry for taking so long!! Here's what happened. This page ;; ;; http://angg.twu.net/glyphs.html ;; ;; tells a bit about the hacked 256-char fonts that I created many ;; years before UTF-8 became standard, and that I used for ages in ;; some of my notes and .tex files... I wanted to maintain ;; compatibility with the files that used those fonts, and this turned ;; out to be very hard - these hacked fonts only worked in files and ;; buffers in which the encoding was "raw-text", ;; ;; (find-elnode "Non-ASCII Characters") ;; (find-elnode "Disabling Multibyte" "unibyte") ;; (find-elnode "Disabling Multibyte" "raw-text") ;; ;; and before 2019 I had a *very* poor understanding of how Emacs ;; converts between unibyte and multibyte and between raw-text, ;; latin-1 and utf-8... ;; «.ee-tolatin1» (to "ee-tolatin1") ;; «.ee-tolatin1-re» (to "ee-tolatin1-re") ;;; _ _ _ _ _ ;;; ___ ___ | |_ ___ | | __ _| |_(_)_ __ / | ;;; / _ \/ _ \_____| __/ _ \| |/ _` | __| | '_ \| | ;;; | __/ __/_____| || (_) | | (_| | |_| | | | | | ;;; \___|\___| \__\___/|_|\__,_|\__|_|_| |_|_| ;;; ;; «ee-tolatin1» (to ".ee-tolatin1") ;; Original comment: ;; ;; 2017jul29: this is a low-level hack to allow anchors like "«tag»" ;; to work on both unibyte and multibyte buffers and files without ;; requiring the user to set the variable `ee-anchor-format' in the ;; local variables section. (defun ee-to-coding (coding str) (ee-no-properties (decode-coding-string str coding))) (defun ee-tolatin1 (str) "Make STR compatible with both unibyte and multibyte buffers. Convert STR to a multibyte format that works in both unibyte (raw-text) and multibyte (e.g., utf-8) buffers. This may fail if STR contains chars that are not in the latin-1 range. This function is used by `ee-format-as-anchor'." (ee-to-coding 'latin-1 str)) ;;; _ _ _ _ _ ;;; ___ ___ | |_ ___ | | __ _| |_(_)_ __ / | _ __ ___ ;;; / _ \/ _ \_____| __/ _ \| |/ _` | __| | '_ \| |_____| '__/ _ \ ;;; | __/ __/_____| || (_) | | (_| | |_| | | | | |_____| | | __/ ;;; \___|\___| \__\___/|_|\__,_|\__|_|_| |_|_| |_| \___| ;;; ;; «ee-tolatin1-re» (to ".ee-tolatin1-re") ;; 2019feb24: this is a hack! ;; Test code: (find-es "emacs" "unibyte-2019-search") (defun ee-tolatin1-re (re) "Make the regexp RE compatible with the current buffer. This is similar to `ee-tolatin1', but for regexps that contain the \"«»\"s used to delimit anchors. For example, (ee-tolatin1-re \"\\253\\([!-~]\\)\\273\") should return a regexp for anchors that works in the current buffer. This is a hack and a work in progress!!! See the code for comments." (let ((bfcs buffer-file-coding-system)) (cond ((eq bfcs 'iso-latin-1-unix) (ee-tolatin1 re)) ((eq bfcs 'raw-text-unix) re) ((eq bfcs 'utf-8-unix) (ee-tolatin1 re)) (t re)))) (provide 'eev-codings) ;; Local Variables: ;; coding: utf-8-unix ;; no-byte-compile: t ;; End: