To install this package, run in Emacs:
M-x package-install RET el-search RET
This package implements an expression based interactive search tool for Emacs Lisp files and buffers. The pattern language used is a superset of `pcase' patterns. "el-search" is multi file/buffer search capable. It is designed to be fast and easy to use. It offers an occur-like overview of matches and can do query-replace based on the same set of patterns. All searches are added to a history and can be resumed or restarted later. Finally, it allows you to define your own kinds of search patterns and your own multi-search commands. Key bindings ============ Loading this file doesn't install any key bindings - but you probably want some. There are two predefined sets of key bindings. The first set installs bindings mostly of the form "Control-Shift-Letter", e.g. C-S, C-R, C-% etc. These can be installed by calling (el-search-install-shift-bindings) - typically in your init file. For console users (and others), the function `el-search-install-bindings-under-prefix' installs bindings of the form PREFIX LETTER. If you e.g. call (el-search-install-bindings-under-prefix [(meta ?s) ?e]) you install bindings M-s e s, M-s e r, M-s e % etc. When using this function to install key bindings, the bindings are "repeatable" where it makes sense, so that you can for example hit M-s e j s s s a % to reactive the last search, go to the next match three times, then go back to the first match in the current buffer, and finally invoke query-replace. Here is a complete list of key bindings installed when you call (el-search-install-shift-bindings) or (el-search-install-bindings-under-prefix [(meta ?s) ?e]) respectively: C-S, M-s e s (el-search-pattern) Start a search in the current buffer/go to the next match. C-R, M-s e r (el-search-pattern-backwards) Search backwards. C-%, M-s e % (el-search-query-replace) Do a query-replace. M-x el-search-directory Prompt for a directory name and start a multi search for all Emacs-Lisp files in that directory. With prefix arg, recursively search files in subdirectories. C-S, M-s e s in Dired (el-search-dired-marked-files) Like above but uses the marked files and directories. C-S, M-s e s in Ibuffer (el-search-ibuffer-marked-buffers) Search marked buffers in *Ibuffer*. C-O, M-s e o (el-search-occur) Pop up an occur buffer for the current search. C-O or M-RET (from a search pattern prompt) Execute this search command as occur. C-N, M-s e n (el-search-continue-in-next-buffer) Skip over current buffer or file. C-D, M-s e d (el-search-skip-directory) Prompt for a directory name and skip all subsequent files located under this directory. C-A, M-s e a (el-search-from-beginning) Go back to the first match in this buffer or (with prefix arg) completely restart the current search from the first file or buffer. C-J, M-s e j (el-search-jump-to-search-head) Resume the last search from the position of the last visited match, or (with prefix arg) prompt for an old search to resume. C-H, M-s e h (el-search-this-sexp) Grab the symbol or sexp under point and initiate an el-search for other occurrences. M-x el-search-to-register Save the current search to an Emacs register. Use C-x r j (`jump-to-register') to make that search current and jump to the latest position. The setup you'll need for your init file is trivial: just define the key bindings you want to use (all important commands are autoloaded) and you are done. Usage ===== The main user entry point `el-search-pattern' (C-S) is analogue to `isearch-forward'. You are prompted for a `pcase'-style search pattern using an `emacs-lisp-mode' minibuffer. After hitting RET it searches the current buffer from point for matching expressions. For any match, point is put at the beginning of the expression found (unlike isearch which puts point at the end of matches). Hit C-S again to go to the next match etc. Syntax and semantics of search patterns are identical to that of `pcase' patterns, plus additionally defined pattern types especially useful for matching parts of programs. The (only) difference to the `pcase' macro is that the expressions found in buffers and files are tried to be matched instead of a given expression. It doesn't matter how code is actually formatted. Comments are ignored, and strings are treated as atomic objects (their contents are not being searched). Example 1: if you enter 97 at the prompt, el-search will find any occurrence of the integer 97 in the code, but not 97.0 or 977 or (+ 90 7) or "My string containing 97" or symbol_97. OTOH it will find any printed representation of 97, e.g. #x61 or ?a. Example 2: If you enter the pattern `(defvar ,_) you search for all `defvar' forms that don't specify an init value. The following pattern will search for `defvar's with a docstring whose first line is longer than 70 characters: `(defvar ,_ ,_ ,(and (pred stringp) s (guard (< 70 (length (car (split-string s "\n"))))))) Put simply, el-search is a tool to match representations of symbolic expressions written in a buffer or file. Most of the time, but not necessarily, this is Elisp code. El-search has no semantic understanding of the meaning of these s-exps as a program. For example, if you define a macro `my-defvar' that expands to `defvar' forms, the pattern `(defvar ,_) will not match any equivalent `my-defvar' form, it just matches any lists of two elements with the first element being the symbol `defvar'. You can define your own pattern types with `el-search-defpattern' which is analogue to `defmacro'. See C-h f `el-search-pattern' for a list of predefined additional pattern types, and C-h f pcase for the basic pcase patterns. Some more pattern definitions can be found in the file "el-search-x" which is part of this package but not automatically loaded. Multi Searching =============== "el-search" is capable of performing "multi searches" - searches spanning multiple files or buffers. When no more matches can be found in the current file or buffer, the search automatically switches to the next. Examples for search commands starting a multi search are `el-search-buffers' (search all living elisp mode buffers), `el-search-directory' (search all elisp files in a specified directory), `el-search-emacs-elisp-sources' (search all Emacs elisp sources) and `el-search-dired-marked-files'. Actually, every search is internally a multi search. You can pause any (multi) search by just doing something different (no quitting is needed), the state of the search is automatically saved. You can later continue searching by calling `el-search-jump-to-search-head' (C-J): this command jumps to the last match and re-activates the search. `el-search-continue-in-next-buffer' (C-N) skips all remaining matches in the current buffer and continues searching in the next buffer. `el-search-skip-directory' even skips all subsequent files under a specified directory. El-Occur ======== To get an occur-like overview buffer, you can use the usual commands to initiate a search. You can either hit C-O from a pattern prompt instead of RET to confirm your input and start the search as noninteractive occur search. Alternatively, you can always call `el-search-occur' (C-O) to start an occur for the latest started search. The *El Occur* buffer uses an adjusted emacs-lisp-mode. RET on a match gives you a pop-up window displaying the position of the match in that buffer or file. With S-tab you can (un)collapse all file sections like in `org-mode' to see only file names and the number of matches, or everything. Tab folds and unfolds expressions (this uses hideshow; initially, all expressions are folded to one line) and sections at the beginning of headlines. Multiple multi searches ======================= Every search is collected in a history. You can resume older searches from the position of the last match by calling `el-search-jump-to-search-head' (C-J) with a prefix argument. That let's you select an older search to resume and switches to the buffer and position where this search had been suspended. Query-replace ============= You can replace expressions with command `el-search-query-replace'. You are queried for a pattern and a replacement expression. For each match of the pattern, the replacement expression is evaluated with the bindings created by pattern matching in effect, and printed to a string to produce the replacement. Example: In some buffer you want to swap the two expressions at the places of the first two arguments in all calls of function `foo', so that e.g. (foo 'a (* 2 (+ 3 4)) t) becomes (foo (* 2 (+ 3 4)) 'a t). This will do it: M-x el-search-query-replace RET `(foo ,a ,b . ,rest) RET `(foo ,b ,a . ,rest) RET Type y to replace a match and go to the next one, r to replace without moving, SPC or n to go to the next match and ! to replace all remaining matches automatically. q quits. And ? shows a quick help summarizing all of these keys. It is possible to replace a match with more than one expression using "splicing mode". When it is active, the replacement expression must evaluate to a list, and is spliced into the buffer for any match. Use s from the prompt to toggle splicing mode in an `el-search-query-replace' session. Multi query-replace =================== To query-replace in multiple files or buffers at once, call `el-search-query-replace' directly after starting a search whose search domain is the set of files and buffers you want to treat. Answer "yes" to the prompt asking whether you want the started search drive the query-replace. The user interface is self-explanatory. It is always possible to resume an aborted query-replace session even if you did other stuff in the meantime (including other `el-search-query-replace' invocations). Since internally every query-replace is driven by a search, call `el-search-jump-to-search-head' (maybe with a prefix arg) to make that search current, and invoke `el-search-query-replace' (with the default bindings, this would be C-J C-% or C-x o j %). This will continue the query-replace session from where you left. Advanced usage: Replacement rules for semi-automatic code rewriting =================================================================== When you want to rewrite larger code parts programmatically, it can often be useful to define a dedicated pattern type to perform the replacement. Here is an example: You heard that in many situations, `dolist' is faster than an equivalent `mapc'. You use `mapc' quite often in your code and want to query-replace many occurrences in your stuff. Instead of using an ad hoc replacing rule, it's cleaner to define a dedicated named pattern type using `el-search-defpattern'. Make this pattern accept an argument and use it to bind a replacement expression to a variable you specify. In query-replace, specify that variable as replacement expression. In our case, the pattern could look like this: (el-search-defpattern el-search-mapc->dolist (new) (let ((var (make-symbol "var")) (body (make-symbol "body")) (list (make-symbol "list"))) `(and `(mapc (lambda (,,var) . ,,body) ,,list) (let ,new `(dolist (,,var ,,list) . ,,body))))) The first condition in the `and' performs the matching and binds the essential parts of the `mapc' form to helper variables. The second, the `let', part, binds the specified variable NEW to the rewritten expression - in our case, a `dolist' form is constructed with the remembered code parts filled in. Now after this preparatory work, for `el-search-query-replace' you can simply specify (literally!) the following rule: (el-search-mapc->dolist repl) -> repl Acknowledgments =============== Thanks to Stefan Monnier for corrections and advice. Known Limitations ================= - Replacing: in some cases the read syntax of forms is changing due to reading-printing. "Some" because we can handle this problem in most cases. - Similar: comments are normally preserved (where it makes sense). But when replacing like `(foo ,a ,b) -> `(foo ,b ,a) in a content like (foo a ;; comment b) the comment will be lost. - Something like '(1 #1#) is unmatchable (because it is un`read'able without context). For a similar reason it is currently not possible to allow a replacement to contain uninterned symbols or repeated/circular parts. BUGS ==== - l is very slow for very long lists. E.g. C-S-e (l "test") - Emacs bug#30132: 27.0.50; "scan-sexps and ##": Occurrences of the syntax "##" (a syntax for an interned symbol whose name is the empty string) can lead to errors while searching. - In *El Occur* buffers, when there are adjacent or nested matches, the movement commands (el-search-occur-previous-match, el-search-occur-next-match aka n and p) may skip matches, and the shown match count can be inaccurate. TODO: - There should be a way to go back to the starting position, like in Isearch, which does this with (push-mark isearch-opoint t) in `isearch-done'. - Add a help command that can be called while searching. - Make searching work in comments, too? (-> `parse-sexp-ignore-comments'). Related: should the pattern `symbol' also match strings that contain matches for a symbol so that it's possible to replace occurrences of a symbol in docstrings? - Port this package to non Emacs Lisp modes? How? Would it already work using only syntax tables, sexp scanning and font-lock? - Replace: pause and warn when replacement might be wrong (ambiguous reader syntaxes; lost comments, comments that can't non-ambiguously be assigned to rewritten code) - There could be something much better than pp to format the replacement, or pp should be improved. NEWS: Please see the NEWS file in this directory.
Some of the user visible news were: Version: 1.6.1 New function `el-search-looking-at', the el-search version of `looking-at'. Version: 1.5.2 The new command `el-search-to-register' allows to save the current search (including its state) to a register and later make that search current again with `jump-to-register' (C-x r j). Version: 1.5.1 The new command `el-search-ibuffer-marked-buffers' el-searches the marked buffers in *Ibuffer*. Version: 1.5 The new function `el-search-install-bindings-under-prefix' can be used to install repeatable versions of the el-search commands under a prefix key. Version: 220.127.116.11 The new option value 'ask-multi for el-search-auto-save-buffers, which is also the new default, makes el-search only prompt for whether to save buffers for multi-buffer query-replace sessions. For single buffer sessions, no prompt, and you can/should save yourself. I find that behavior slightly more convenient than 'ask in most cases.