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diff --git a/lisp/obsolete/sregex.el b/lisp/obsolete/sregex.el deleted file mode 100644 index f8722f6129e..00000000000 --- a/lisp/obsolete/sregex.el +++ /dev/null @@ -1,605 +0,0 @@ -;;; sregex.el --- symbolic regular expressions -*- lexical-binding: t; -*- - -;; Copyright (C) 1997-1998, 2000-2022 Free Software Foundation, Inc. - -;; Author: Bob Glickstein <bobg+sregex@zanshin.com> -;; Maintainer: emacs-devel@gnu.org -;; Keywords: extensions -;; Obsolete-since: 24.1 - -;; 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 <https://www.gnu.org/licenses/>. - -;;; Commentary: - -;; This package allows you to write regular expressions using a -;; totally new, Lisp-like syntax. - -;; A "symbolic regular expression" (sregex for short) is a Lisp form -;; that, when evaluated, produces the string form of the specified -;; regular expression. Here's a simple example: - -;; (sregexq (or "Bob" "Robert")) => "Bob\\|Robert" - -;; As you can see, an sregex is specified by placing one or more -;; special clauses in a call to `sregexq'. The clause in this case is -;; the `or' of two strings (not to be confused with the Lisp function -;; `or'). The list of allowable clauses appears below. - -;; With sregex, it is never necessary to "escape" magic characters -;; that are meant to be taken literally; that happens automatically. -;; For example: - -;; (sregexq "M*A*S*H") => "M\\*A\\*S\\*H" - -;; It is also unnecessary to "group" parts of the expression together -;; to overcome operator precedence; that also happens automatically. -;; For example: - -;; (sregexq (opt (or "Bob" "Robert"))) => "\\(?:Bob\\|Robert\\)?" - -;; It *is* possible to group parts of the expression in order to refer -;; to them with numbered backreferences: - -;; (sregexq (group (or "Go" "Run")) -;; ", Spot, " -;; (backref 1)) => "\\(Go\\|Run\\), Spot, \\1" - -;; `sregexq' is a macro. Each time it is used, it constructs a simple -;; Lisp expression that then invokes a moderately complex engine to -;; interpret the sregex and render the string form. Because of this, -;; I don't recommend sprinkling calls to `sregexq' throughout your -;; code, the way one normally does with string regexes (which are -;; cheap to evaluate). Instead, it's wiser to precompute the regexes -;; you need wherever possible instead of repeatedly constructing the -;; same ones over and over. Example: - -;; (let ((field-regex (sregexq (opt "resent-") -;; (or "to" "cc" "bcc")))) -;; ... -;; (while ... -;; ... -;; (re-search-forward field-regex ...) -;; ...)) - -;; The arguments to `sregexq' are automatically quoted, but the -;; flipside of this is that it is not straightforward to include -;; computed (i.e., non-constant) values in `sregexq' expressions. So -;; `sregex' is a function that is like `sregexq' but which does not -;; automatically quote its values. Literal sregex clauses must be -;; explicitly quoted like so: - -;; (sregex '(or "Bob" "Robert")) => "Bob\\|Robert" - -;; but computed clauses can be included easily, allowing for the reuse -;; of common clauses: - -;; (let ((dotstar '(0+ any)) -;; (whitespace '(1+ (syntax ?-))) -;; (digits '(1+ (char (?0 . ?9))))) -;; (sregex 'bol dotstar ":" whitespace digits)) => "^.*:\\s-+[0-9]+" - -;; To use this package in a Lisp program, simply (require 'sregex). - -;; Here are the clauses allowed in an `sregex' or `sregexq' -;; expression: - -;; - a string -;; This stands for the literal string. If it contains -;; metacharacters, they will be escaped in the resulting regex -;; (using `regexp-quote'). - -;; - the symbol `any' -;; This stands for ".", a regex matching any character except -;; newline. - -;; - the symbol `bol' -;; Stands for "^", matching the empty string at the beginning of a line - -;; - the symbol `eol' -;; Stands for "$", matching the empty string at the end of a line - -;; - (group CLAUSE ...) -;; Groups the given CLAUSEs using "\\(" and "\\)". - -;; - (sequence CLAUSE ...) - -;; Groups the given CLAUSEs; may or may not use "\\(?:" and "\\)". -;; Clauses grouped by `sequence' do not count for purposes of -;; numbering backreferences. Use `sequence' in situations like -;; this: - -;; (sregexq (or "dog" "cat" -;; (sequence (opt "sea ") "monkey"))) -;; => "dog\\|cat\\|\\(?:sea \\)?monkey" - -;; where a single `or' alternate needs to contain multiple -;; subclauses. - -;; - (backref N) -;; Matches the same string previously matched by the Nth "group" in -;; the same sregex. N is a positive integer. - -;; - (or CLAUSE ...) -;; Matches any one of the CLAUSEs by separating them with "\\|". - -;; - (0+ CLAUSE ...) -;; Concatenates the given CLAUSEs and matches zero or more -;; occurrences by appending "*". - -;; - (1+ CLAUSE ...) -;; Concatenates the given CLAUSEs and matches one or more -;; occurrences by appending "+". - -;; - (opt CLAUSE ...) -;; Concatenates the given CLAUSEs and matches zero or one occurrence -;; by appending "?". - -;; - (repeat MIN MAX CLAUSE ...) -;; Concatenates the given CLAUSEs and constructs a regex matching at -;; least MIN occurrences and at most MAX occurrences. MIN must be a -;; non-negative integer. MAX must be a non-negative integer greater -;; than or equal to MIN; or MAX can be nil to mean "infinity." - -;; - (char CHAR-CLAUSE ...) -;; Creates a "character class" matching one character from the given -;; set. See below for how to construct a CHAR-CLAUSE. - -;; - (not-char CHAR-CLAUSE ...) -;; Creates a "character class" matching any one character not in the -;; given set. See below for how to construct a CHAR-CLAUSE. - -;; - the symbol `bot' -;; Stands for "\\`", matching the empty string at the beginning of -;; text (beginning of a string or of a buffer). - -;; - the symbol `eot' -;; Stands for "\\'", matching the empty string at the end of text. - -;; - the symbol `point' -;; Stands for "\\=", matching the empty string at point. - -;; - the symbol `word-boundary' -;; Stands for "\\b", matching the empty string at the beginning or -;; end of a word. - -;; - the symbol `not-word-boundary' -;; Stands for "\\B", matching the empty string not at the beginning -;; or end of a word. - -;; - the symbol `bow' -;; Stands for "\\<", matching the empty string at the beginning of a -;; word. - -;; - the symbol `eow' -;; Stands for "\\>", matching the empty string at the end of a word. - -;; - the symbol `wordchar' -;; Stands for the regex "\\w", matching a word-constituent character -;; (as determined by the current syntax table) - -;; - the symbol `not-wordchar' -;; Stands for the regex "\\W", matching a non-word-constituent -;; character. - -;; - (syntax CODE) -;; Stands for the regex "\\sCODE", where CODE is a syntax table code -;; (a single character). Matches any character with the requested -;; syntax. - -;; - (not-syntax CODE) -;; Stands for the regex "\\SCODE", where CODE is a syntax table code -;; (a single character). Matches any character without the -;; requested syntax. - -;; - (regex REGEX) -;; This is a "trapdoor" for including ordinary regular expression -;; strings in the result. Some regular expressions are clearer when -;; written the old way: "[a-z]" vs. (sregexq (char (?a . ?z))), for -;; instance. - -;; Each CHAR-CLAUSE that is passed to (char ...) and (not-char ...) -;; has one of the following forms: - -;; - a character -;; Adds that character to the set. - -;; - a string -;; Adds all the characters in the string to the set. - -;; - A pair (MIN . MAX) -;; Where MIN and MAX are characters, adds the range of characters -;; from MIN through MAX to the set. - -;;; To do: - -;; An earlier version of this package could optionally translate the -;; symbolic regex into other languages' syntaxes, e.g. Perl. For -;; instance, with Perl syntax selected, (sregexq (or "ab" "cd")) would -;; yield "ab|cd" instead of "ab\\|cd". It might be useful to restore -;; such a facility. - -;; - handle multibyte chars in sregex--char-aux -;; - add support for character classes ([:blank:], ...) -;; - add support for non-greedy operators *? and +? -;; - bug: (sregexq (opt (opt ?a))) returns "a??" which is a non-greedy "a?" - -;;; Code: - -(eval-when-compile (require 'cl-lib)) - -;; Compatibility code for when we didn't have shy-groups -(defvar sregex--current-sregex nil) -(defun sregex-info () nil) -(defmacro sregex-save-match-data (&rest forms) (cons 'save-match-data forms)) -(defun sregex-replace-match (r &optional f l str subexp _x) - (replace-match r f l str subexp)) -(defun sregex-match-string (c &optional i _x) (match-string c i)) -(defun sregex-match-string-no-properties (count &optional in-string _sregex) - (match-string-no-properties count in-string)) -(defun sregex-match-beginning (count &optional _sregex) (match-beginning count)) -(defun sregex-match-end (count &optional _sregex) (match-end count)) -(defun sregex-match-data (&optional _sregex) (match-data)) -(defun sregex-backref-num (n &optional _sregex) n) - - -(defun sregex (&rest exps) - "Symbolic regular expression interpreter. -This is exactly like `sregexq' (q.v.) except that it evaluates all its -arguments, so literal sregex clauses must be quoted. For example: - - (sregex \\='(or \"Bob\" \"Robert\")) => \"Bob\\\\|Robert\" - -An argument-evaluating sregex interpreter lets you reuse sregex -subexpressions: - - (let ((dotstar \\='(0+ any)) - (whitespace \\='(1+ (syntax ?-))) - (digits \\='(1+ (char (?0 . ?9))))) - (sregex \\='bol dotstar \":\" whitespace digits)) => \"^.*:\\\\s-+[0-9]+\"" - (sregex--sequence exps nil)) - -(defmacro sregexq (&rest exps) - "Symbolic regular expression interpreter. -This macro allows you to specify a regular expression (regexp) in -symbolic form, and converts it into the string form required by Emacs's -regex functions such as `re-search-forward' and `looking-at'. Here is -a simple example: - - (sregexq (or \"Bob\" \"Robert\")) => \"Bob\\\\|Robert\" - -As you can see, an sregex is specified by placing one or more special -clauses in a call to `sregexq'. The clause in this case is the `or' -of two strings (not to be confused with the Lisp function `or'). The -list of allowable clauses appears below. - -With `sregex', it is never necessary to \"escape\" magic characters -that are meant to be taken literally; that happens automatically. -For example: - - (sregexq \"M*A*S*H\") => \"M\\\\*A\\\\*S\\\\*H\" - -It is also unnecessary to \"group\" parts of the expression together -to overcome operator precedence; that also happens automatically. -For example: - - (sregexq (opt (or \"Bob\" \"Robert\"))) => \"\\\\(Bob\\\\|Robert\\\\)?\" - -It *is* possible to group parts of the expression in order to refer -to them with numbered backreferences: - - (sregexq (group (or \"Go\" \"Run\")) - \", Spot, \" - (backref 1)) => \"\\\\(Go\\\\|Run\\\\), Spot, \\\\1\" - -If `sregexq' needs to introduce its own grouping parentheses, it will -automatically renumber your backreferences: - - (sregexq (opt \"resent-\") - (group (or \"to\" \"cc\" \"bcc\")) - \": \" - (backref 1)) => \"\\\\(resent-\\\\)?\\\\(to\\\\|cc\\\\|bcc\\\\): \\\\2\" - -`sregexq' is a macro. Each time it is used, it constructs a simple -Lisp expression that then invokes a moderately complex engine to -interpret the sregex and render the string form. Because of this, I -don't recommend sprinkling calls to `sregexq' throughout your code, -the way one normally does with string regexes (which are cheap to -evaluate). Instead, it's wiser to precompute the regexes you need -wherever possible instead of repeatedly constructing the same ones -over and over. Example: - - (let ((field-regex (sregexq (opt \"resent-\") - (or \"to\" \"cc\" \"bcc\")))) - ... - (while ... - ... - (re-search-forward field-regex ...) - ...)) - -The arguments to `sregexq' are automatically quoted, but the -flipside of this is that it is not straightforward to include -computed (i.e., non-constant) values in `sregexq' expressions. So -`sregex' is a function that is like `sregexq' but which does not -automatically quote its values. Literal sregex clauses must be -explicitly quoted like so: - - (sregex \\='(or \"Bob\" \"Robert\")) => \"Bob\\\\|Robert\" - -but computed clauses can be included easily, allowing for the reuse -of common clauses: - - (let ((dotstar \\='(0+ any)) - (whitespace \\='(1+ (syntax ?-))) - (digits \\='(1+ (char (?0 . ?9))))) - (sregex \\='bol dotstar \":\" whitespace digits)) => \"^.*:\\\\s-+[0-9]+\" - -Here are the clauses allowed in an `sregex' or `sregexq' expression: - -- a string - This stands for the literal string. If it contains - metacharacters, they will be escaped in the resulting regex - (using `regexp-quote'). - -- the symbol `any' - This stands for \".\", a regex matching any character except - newline. - -- the symbol `bol' - Stands for \"^\", matching the empty string at the beginning of a line - -- the symbol `eol' - Stands for \"$\", matching the empty string at the end of a line - -- (group CLAUSE ...) - Groups the given CLAUSEs using \"\\\\(\" and \"\\\\)\". - -- (sequence CLAUSE ...) - - Groups the given CLAUSEs; may or may not use \"\\\\(\" and \"\\\\)\". - Clauses grouped by `sequence' do not count for purposes of - numbering backreferences. Use `sequence' in situations like - this: - - (sregexq (or \"dog\" \"cat\" - (sequence (opt \"sea \") \"monkey\"))) - => \"dog\\\\|cat\\\\|\\\\(?:sea \\\\)?monkey\" - - where a single `or' alternate needs to contain multiple - subclauses. - -- (backref N) - Matches the same string previously matched by the Nth \"group\" in - the same sregex. N is a positive integer. - -- (or CLAUSE ...) - Matches any one of the CLAUSEs by separating them with \"\\\\|\". - -- (0+ CLAUSE ...) - Concatenates the given CLAUSEs and matches zero or more - occurrences by appending \"*\". - -- (1+ CLAUSE ...) - Concatenates the given CLAUSEs and matches one or more - occurrences by appending \"+\". - -- (opt CLAUSE ...) - Concatenates the given CLAUSEs and matches zero or one occurrence - by appending \"?\". - -- (repeat MIN MAX CLAUSE ...) - Concatenates the given CLAUSEs and constructs a regex matching at - least MIN occurrences and at most MAX occurrences. MIN must be a - non-negative integer. MAX must be a non-negative integer greater - than or equal to MIN; or MAX can be nil to mean \"infinity.\" - -- (char CHAR-CLAUSE ...) - Creates a \"character class\" matching one character from the given - set. See below for how to construct a CHAR-CLAUSE. - -- (not-char CHAR-CLAUSE ...) - Creates a \"character class\" matching any one character not in the - given set. See below for how to construct a CHAR-CLAUSE. - -- the symbol `bot' - Stands for \"\\\\\\=`\", matching the empty string at the beginning of - text (beginning of a string or of a buffer). - -- the symbol `eot' - Stands for \"\\\\'\", matching the empty string at the end of text. - -- the symbol `point' - Stands for \"\\\\=\\=\", matching the empty string at point. - -- the symbol `word-boundary' - Stands for \"\\\\b\", matching the empty string at the beginning or - end of a word. - -- the symbol `not-word-boundary' - Stands for \"\\\\B\", matching the empty string not at the beginning - or end of a word. - -- the symbol `bow' - Stands for \"\\\\=\\<\", matching the empty string at the beginning of a - word. - -- the symbol `eow' - Stands for \"\\\\=\\>\", matching the empty string at the end of a word. - -- the symbol `wordchar' - Stands for the regex \"\\\\w\", matching a word-constituent character - (as determined by the current syntax table) - -- the symbol `not-wordchar' - Stands for the regex \"\\\\W\", matching a non-word-constituent - character. - -- (syntax CODE) - Stands for the regex \"\\\\sCODE\", where CODE is a syntax table code - (a single character). Matches any character with the requested - syntax. - -- (not-syntax CODE) - Stands for the regex \"\\\\SCODE\", where CODE is a syntax table code - (a single character). Matches any character without the - requested syntax. - -- (regex REGEX) - This is a \"trapdoor\" for including ordinary regular expression - strings in the result. Some regular expressions are clearer when - written the old way: \"[a-z]\" vs. (sregexq (char (?a . ?z))), for - instance. - -Each CHAR-CLAUSE that is passed to (char ...) and (not-char ...) -has one of the following forms: - -- a character - Adds that character to the set. - -- a string - Adds all the characters in the string to the set. - -- A pair (MIN . MAX) - Where MIN and MAX are characters, adds the range of characters - from MIN through MAX to the set." - `(apply 'sregex ',exps)) - -(defun sregex--engine (exp combine) - (cond - ((stringp exp) - (if (and combine - (eq combine 'suffix) - (/= (length exp) 1)) - (concat "\\(?:" (regexp-quote exp) "\\)") - (regexp-quote exp))) - ((symbolp exp) - (cl-ecase exp - (any ".") - (bol "^") - (eol "$") - (wordchar "\\w") - (not-wordchar "\\W") - (bot "\\`") - (eot "\\'") - (point "\\=") - (word-boundary "\\b") - (not-word-boundary "\\B") - (bow "\\<") - (eow "\\>"))) - ((consp exp) - (funcall (intern (concat "sregex--" - (symbol-name (car exp)))) - (cdr exp) - combine)) - (t (error "Invalid expression: %s" exp)))) - -(defun sregex--sequence (exps combine) - (if (= (length exps) 1) (sregex--engine (car exps) combine) - (let ((re (mapconcat - (lambda (e) (sregex--engine e 'concat)) - exps ""))) - (if (eq combine 'suffix) - (concat "\\(?:" re "\\)") - re)))) - -(defun sregex--or (exps combine) - (if (= (length exps) 1) (sregex--engine (car exps) combine) - (let ((re (mapconcat - (lambda (e) (sregex--engine e 'or)) - exps "\\|"))) - (if (not (eq combine 'or)) - (concat "\\(?:" re "\\)") - re)))) - -(defun sregex--group (exps _combine) (concat "\\(" (sregex--sequence exps nil) "\\)")) - -(defun sregex--backref (exps _combine) (concat "\\" (int-to-string (car exps)))) -(defun sregex--opt (exps _combine) (concat (sregex--sequence exps 'suffix) "?")) -(defun sregex--0+ (exps _combine) (concat (sregex--sequence exps 'suffix) "*")) -(defun sregex--1+ (exps _combine) (concat (sregex--sequence exps 'suffix) "+")) - -(defun sregex--char (exps _combine) (sregex--char-aux nil exps)) -(defun sregex--not-char (exps _combine) (sregex--char-aux t exps)) - -(defun sregex--syntax (exps _combine) (format "\\s%c" (car exps))) -(defun sregex--not-syntax (exps _combine) (format "\\S%c" (car exps))) - -(defun sregex--regex (exps combine) - (if combine (concat "\\(?:" (car exps) "\\)") (car exps))) - -(defun sregex--repeat (exps _combine) - (let* ((min (or (pop exps) 0)) - (minstr (number-to-string min)) - (max (pop exps))) - (concat (sregex--sequence exps 'suffix) - (concat "\\{" minstr "," - (when max (number-to-string max)) "\\}")))) - -(defun sregex--char-range (start end) - (let ((startc (char-to-string start)) - (endc (char-to-string end))) - (cond - ((> end (+ start 2)) (concat startc "-" endc)) - ((> end (+ start 1)) (concat startc (char-to-string (1+ start)) endc)) - ((> end start) (concat startc endc)) - (t startc)))) - -(defun sregex--char-aux (complement args) - ;; regex-opt does the same, we should join effort. - (let ((chars (make-bool-vector 256 nil))) ; Yeah, right! - (dolist (arg args) - (cond ((integerp arg) (aset chars arg t)) - ((stringp arg) (mapc (lambda (c) (aset chars c t)) arg)) - ((consp arg) - (let ((start (car arg)) - (end (cdr arg))) - (when (> start end) - (let ((tmp start)) (setq start end) (setq end tmp))) - ;; now start <= end - (let ((i start)) - (while (<= i end) - (aset chars i t) - (setq i (1+ i)))))))) - ;; now chars is a map of the characters in the class - (let ((caret (aref chars ?^)) - (dash (aref chars ?-)) - (class (if (aref chars ?\]) "]" ""))) - (aset chars ?^ nil) - (aset chars ?- nil) - (aset chars ?\] nil) - - (let (start end) - (dotimes (i 256) - (if (aref chars i) - (progn - (unless start (setq start i)) - (setq end i) - (aset chars i nil)) - (when start - (setq class (concat class (sregex--char-range start end))) - (setq start nil)))) - (if start - (setq class (concat class (sregex--char-range start end))))) - - (if (> (length class) 0) - (setq class (concat class (if caret "^") (if dash "-"))) - (setq class (concat class (if dash "-") (if caret "^")))) - (if (and (not complement) (= (length class) 1)) - (regexp-quote class) - (concat "[" (if complement "^") class "]"))))) - -(provide 'sregex) - -;;; sregex.el ends here |