;; ============
;;
;;
-;; The main user entry point is the command `el-search-pattern'. It
+;; The main user entry point is `el-search-pattern'. This command
;; prompts for a `pcase' pattern and searches the current buffer for
-;; expressions that are matched by it when read. Point is put at the
-;; beginning of the expression found (unlike isearch).
+;; matching expressions by iteratively `read'ing buffer contents. For
+;; any match, point is put at the beginning of the expression found
+;; (unlike isearch which puts point at the end of matches).
;;
;; It doesn't matter how the code is actually formatted. Comments are
-;; ignored by the search, and strings are treated as objects, their
-;; contents are not being searched.
+;; ignored, and strings are treated as atomic objects, their contents
+;; are not being searched.
;;
;; Example 1: if you enter
;;
;; ,(and s (guard (< 70 (length (car (split-string s "\n")))))))
;;
;;
+;; When a search pattern is processed, the searched buffer is current
+;; with point at the beginning of the currently tested expression.
+;;
+;;
+;; Example 3:
+;;
+;; I can be useful to use (guard EXP) patterns for side effects.
+;;
+;; The following pattern will search for symbols defined in any
+;; library whose name starts with "cl". As a side effect, it prints
+;; the current line number, whether we have a macro or a function, and
+;; the defining file in the echo area for each match:
+;;
+;; (and (pred symbolp)
+;; (let file (symbol-file exp))
+;; (guard file)
+;; (let lib-name (file-name-sans-extension
+;; (file-name-nondirectory file)))
+;; (guard (string-match-p "^cl" lib-name))
+;; (or (and (pred macrop) (let type "macro "))
+;; (and (pred functionp) (let type "function "))
+;; (let type ""))
+;; (guard (message "Line %d: %s`%S' (from \"%s\")"
+;; (line-number-at-pos)
+;; type
+;; exp
+;; lib-name)))
+;;
+;; `message' never returns nil, so the last `guard' always "matches".
+;;
+;;
;; Convenience
;; ===========
;;
-;; For expression input, the minibuffer prompts here uses
-;; `emacs-lisp-mode'.
+;; For pattern input, the minibuffer is put into `emacs-lisp-mode'.
+;;
+;; Any input PATTERN is silently transformed into (and exp PATTERN)
+;; so that you can always refer to the whole currently tested
+;; expression via the variable `exp'.
+;;
+;; Example 4:
;;
-;; When reading a search pattern in the minibuffer, the input is
-;; automatically wrapped into `(and exp ,(read input)). So, if you
-;; want to search a buffer for symbols that are defined in "cl-lib",
-;; you can use this pattern
+;; If you want to search a buffer for symbols that are defined in
+;; "cl-lib", you can use this pattern
;;
;; (guard (and (symbolp exp)
;; (when-let ((file (symbol-file exp)))
;; (string-match-p "cl-lib\\.elc?$" file))))
;;
-;; without binding the variable `exp'.
+;;
+;; ,----------------------------------------------------------------------
+;; | Q: "But I hate `pcase'! Can't we just do without?" |
+;; | |
+;; | A: Respect that you kept up until here! Just use (guard CODE), where|
+;; | CODE is any normal Elisp expression that returns non-nil when and |
+;; | only when you have a match. Use the variable `exp' to refer to |
+;; | the currently tested expression. Just like in the last example! |
+;; `----------------------------------------------------------------------
+;;
+;;
+;; It's cumbersome to write out the same complicated pattern
+;; constructs in the minibuffer again and again. You can define your
+;; own pcase pattern types for the purpose of el-search with
+;; `el-search-defpattern'. It is just like `pcase-defmacro', but the
+;; effect is limited to this package. See C-h f `el-search-pattern'
+;; for a list of predefined additional pattern forms.
;;
;;
;; Replacing
;;
;; - improve docstrings
;;
-;; - add more examples
-;;
;; - handle more reader syntaxes, e.g. #n, #n#
;;
;; - Implement sessions; add multi-file support based on iterators. A
(error (forward-char))))
res))
+(defvar el-search--pcase-macros '()
+ "List of additional \"el-search\" pcase macros.")
+
+(defun el-search--make-docstring ()
+ ;; code mainly from `pcase--make-docstring'
+ (let* ((main (documentation (symbol-function 'el-search-pattern) 'raw))
+ (ud (help-split-fundoc main 'pcase)))
+ (require 'help-fns)
+ (with-temp-buffer
+ (insert (or (cdr ud) main))
+ (mapc
+ (pcase-lambda (`(,symbol . ,fun))
+ (when-let ((doc (documentation fun)))
+ (insert "\n\n-- ")
+ (setq doc (help-fns--signature symbol doc nil fun nil))
+ (insert "\n" (or doc "Not documented."))))
+ (reverse el-search--pcase-macros))
+ (let ((combined-doc (buffer-string)))
+ (if ud (help-add-fundoc-usage combined-doc (car ud)) combined-doc)))))
+
+(put 'el-search-pattern 'function-documentation '(el-search--make-docstring))
+
+(defmacro el-search-defpattern (name args &rest body)
+ "Like `pcase-defmacro', but limited to el-search patterns.
+The semantics is exactly that of `pcase-defmacro', but the scope
+of the definitions is limited to \"el-search\"."
+ (declare (indent 2) (debug defun))
+ `(setf (alist-get ',name el-search--pcase-macros)
+ (lambda ,args ,@body)))
+
+(el-search-defpattern string (&rest regexps)
+ "Matches any string that is matched by all REGEXPS."
+ (let ((string (make-symbol "string"))
+ (regexp (make-symbol "regexp")))
+ `(and (pred stringp)
+ (pred (lambda (,string)
+ (cl-every
+ (lambda (,regexp) (string-match-p ,regexp ,string))
+ (list ,@regexps)))))))
+
+(el-search-defpattern symbol (&rest regexps)
+ "Matches any symbol whose name is matched by all REGEXPS."
+ `(and (pred symbolp)
+ (app symbol-name (string ,@regexps))))
+
+(defun el-search--match-symbol-file (regexp symbol)
+ (when-let ((symbol-file (and (symbolp symbol)
+ (symbol-file symbol))))
+ (string-match-p
+ (if (symbolp regexp) (concat "\\`" (symbol-name regexp) "\\'") regexp)
+ (file-name-sans-extension (file-name-nondirectory symbol-file)))))
+
+(el-search-defpattern source (regexp)
+ "Matches any symbol whose `symbol-file' is matched by REGEXP.
+
+This pattern matches when the object is a symbol for that
+`symbol-file' returns a (non-nil) FILE-NAME that fulfills
+ (string-match-p REGEXP (file-name-sans-extension
+ (file-name-nondirectory FILENAME)))
+
+REGEXP can also be a symbol, in which case
+
+ (concat \"^\" (symbol-name regexp) \"$\")
+
+is used as regular expression."
+ `(pred (el-search--match-symbol-file ,regexp)))
+
+(defun el-search--match-key-sequence (keys expr)
+ (when-let ((expr-keys (pcase expr
+ ((or (pred stringp) (pred vectorp)) expr)
+ (`(kbd ,(and (pred stringp) string)) (ignore-errors (kbd string))))))
+ (apply #'equal
+ (mapcar (lambda (keys) (ignore-errors (key-description keys)))
+ (list keys expr-keys)))))
+
+(el-search-defpattern keys (key-sequence)
+ "Matches any description of the KEY-SEQUENCE.
+KEY-SEQUENCE is a key description in a format that Emacs
+understands.
+
+This pattern matches any description of the same key sequence.
+
+Example: the pattern
+
+ (keys (kbd \"C-s\"))
+
+matches any of these expressions:
+
+ (kbd \"C-s\")
+ [(control ?s)]
+ \"\\C-s\"
+
+Any of these could be used as equivalent KEY-SEQUENCE in terms of
+this pattern type."
+ `(pred (el-search--match-key-sequence ,key-sequence)))
+
+(defmacro el-search--with-additional-pcase-macros (&rest body)
+ `(cl-letf ,(mapcar (pcase-lambda (`(,symbol . ,fun))
+ `((get ',symbol 'pcase-macroexpander) #',fun))
+ el-search--pcase-macros)
+ ,@body))
+
(defun el-search--matcher (pattern &rest body)
(let ((warning-suppress-log-types '((bytecomp))))
- (byte-compile
- `(lambda (expression)
- (pcase expression
- (,pattern ,@(or body (list t)))
- (_ nil))))))
+ (el-search--with-additional-pcase-macros
+ (byte-compile
+ `(lambda (expression)
+ (pcase expression
+ (,pattern ,@(or body (list t)))
+ (_ nil)))))))
(defun el-search--match-p (matcher expression)
(funcall matcher expression))
;;;###autoload
(defun el-search-pattern (pattern)
- "Do incremental elisp search or resume last search."
+ "Start new or resume last elisp search.
+
+Search current buffer for expressions that are matched by `pcase'
+PATTERN. Use `read' to transform buffer contents into
+expressions.
+
+
+Additional `pcase' pattern types to be used with this command can
+be defined with `el-search-defpattern'.
+
+The following additional pattern types are currently defined:\n"
(interactive (list (if (eq this-command last-command)
el-search-current-pattern
(let ((pattern