* fileio.c (Finsert_file_contents): Avoid double-close.
[emacs.git] / lisp / eshell / esh-cmd.el
blob69dc6c76b416c25aa5e9f818c609dab14025df7b
1 ;;; esh-cmd.el --- command invocation
3 ;; Copyright (C) 1999-2013 Free Software Foundation, Inc.
5 ;; Author: John Wiegley <johnw@gnu.org>
7 ;; This file is part of GNU Emacs.
9 ;; GNU Emacs is free software: you can redistribute it and/or modify
10 ;; it under the terms of the GNU General Public License as published by
11 ;; the Free Software Foundation, either version 3 of the License, or
12 ;; (at your option) any later version.
14 ;; GNU Emacs is distributed in the hope that it will be useful,
15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 ;; GNU General Public License for more details.
19 ;; You should have received a copy of the GNU General Public License
20 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
22 ;;; Commentary:
24 ;;;_* Invoking external commands
26 ;; External commands cause processes to be created, by loading
27 ;; external executables into memory. This is what most normal shells
28 ;; do, most of the time. For more information, see [External commands].
30 ;;;_* Invoking Lisp functions
32 ;; A Lisp function can be invoked using Lisp syntax, or command shell
33 ;; syntax. For example, to run `dired' to edit the current directory:
35 ;; /tmp $ (dired ".")
37 ;; Or:
39 ;; /tmp $ dired .
41 ;; The latter form is preferable, but the former is more precise,
42 ;; since it involves no translations. See [Argument parsing], to
43 ;; learn more about how arguments are transformed before passing them
44 ;; to commands.
46 ;; Ordinarily, if 'dired' were also available as an external command,
47 ;; the external version would be called in preference to any Lisp
48 ;; function of the same name. To change this behavior so that Lisp
49 ;; functions always take precedence, set
50 ;; `eshell-prefer-lisp-functions' to t.
52 ;;;_* Alias functions
54 ;; Whenever a command is specified using a simple name, such as 'ls',
55 ;; Eshell will first look for a Lisp function of the name `eshell/ls'.
56 ;; If it exists, it will be called in preference to any other command
57 ;; which might have matched the name 'ls' (such as command aliases,
58 ;; external commands, Lisp functions of that name, etc).
60 ;; This is the most flexible mechanism for creating new commands,
61 ;; since it does not pollute the global namespace, yet allows you to
62 ;; use all of Lisp's facilities to define that piece of functionality.
63 ;; Most of Eshell's "builtin" commands are defined as alias functions.
65 ;;;_* Lisp arguments
67 ;; It is possible to invoke a Lisp form as an argument. This can be
68 ;; done either by specifying the form as you might in Lisp, or by
69 ;; using the '$' character to introduce a value-interpolation:
71 ;; echo (+ 1 2)
73 ;; Or
75 ;; echo $(+ 1 2)
77 ;; The two forms are equivalent. The second is required only if the
78 ;; form being interpolated is within a string, or is a subexpression
79 ;; of a larger argument:
81 ;; echo x$(+ 1 2) "String $(+ 1 2)"
83 ;; To pass a Lisp symbol as a argument, use the alternate quoting
84 ;; syntax, since the single quote character is far too overused in
85 ;; shell syntax:
87 ;; echo #'lisp-symbol
89 ;; Backquote can also be used:
91 ;; echo `(list ,lisp-symbol)
93 ;; Lisp arguments are identified using the following regexp:
95 ;;;_* Command hooks
97 ;; There are several hooks involved with command execution, which can
98 ;; be used either to change or augment Eshell's behavior.
101 ;;; Code:
103 (require 'esh-util)
104 (unless (featurep 'xemacs)
105 (require 'eldoc))
106 (require 'esh-arg)
107 (require 'esh-proc)
108 (require 'esh-ext)
110 (eval-when-compile
111 (require 'cl-lib)
112 (require 'pcomplete))
115 (defgroup eshell-cmd nil
116 "Executing an Eshell command is as simple as typing it in and
117 pressing <RET>. There are several different kinds of commands,
118 however."
119 :tag "Command invocation"
120 ;; :link '(info-link "(eshell)Command invocation")
121 :group 'eshell)
123 (defcustom eshell-prefer-lisp-functions nil
124 "If non-nil, prefer Lisp functions to external commands."
125 :type 'boolean
126 :group 'eshell-cmd)
128 (defcustom eshell-lisp-regexp "\\([(`]\\|#'\\)"
129 "A regexp which, if matched at beginning of an argument, means Lisp.
130 Such arguments will be passed to `read', and then evaluated."
131 :type 'regexp
132 :group 'eshell-cmd)
134 (defcustom eshell-pre-command-hook nil
135 "A hook run before each interactive command is invoked."
136 :type 'hook
137 :group 'eshell-cmd)
139 (defcustom eshell-post-command-hook nil
140 "A hook run after each interactive command is invoked."
141 :type 'hook
142 :group 'eshell-cmd)
144 (defcustom eshell-prepare-command-hook nil
145 "A set of functions called to prepare a named command.
146 The command name and its argument are in `eshell-last-command-name'
147 and `eshell-last-arguments'. The functions on this hook can change
148 the value of these symbols if necessary.
150 To prevent a command from executing at all, set
151 `eshell-last-command-name' to nil."
152 :type 'hook
153 :group 'eshell-cmd)
155 (defcustom eshell-named-command-hook nil
156 "A set of functions called before a named command is invoked.
157 Each function will be passed the command name and arguments that were
158 passed to `eshell-named-command'.
160 If any of the functions returns a non-nil value, the named command
161 will not be invoked, and that value will be returned from
162 `eshell-named-command'.
164 In order to substitute an alternate command form for execution, the
165 hook function should throw it using the tag `eshell-replace-command'.
166 For example:
168 (add-hook 'eshell-named-command-hook 'subst-with-cd)
169 (defun subst-with-cd (command args)
170 (throw 'eshell-replace-command
171 (eshell-parse-command \"cd\" args)))
173 Although useless, the above code will cause any non-glob, non-Lisp
174 command (i.e., 'ls' as opposed to '*ls' or '(ls)') to be replaced by a
175 call to `cd' using the arguments that were passed to the function."
176 :type 'hook
177 :group 'eshell-cmd)
179 (defcustom eshell-pre-rewrite-command-hook
180 '(eshell-no-command-conversion
181 eshell-subcommand-arg-values)
182 "A hook run before command rewriting begins.
183 The terms of the command to be rewritten is passed as arguments, and
184 may be modified in place. Any return value is ignored."
185 :type 'hook
186 :group 'eshell-cmd)
188 (defcustom eshell-rewrite-command-hook
189 '(eshell-rewrite-for-command
190 eshell-rewrite-while-command
191 eshell-rewrite-if-command
192 eshell-rewrite-sexp-command
193 eshell-rewrite-initial-subcommand
194 eshell-rewrite-named-command)
195 "A set of functions used to rewrite the command argument.
196 Once parsing of a command line is completed, the next step is to
197 rewrite the initial argument into something runnable.
199 A module may wish to associate special behavior with certain argument
200 syntaxes at the beginning of a command line. They are welcome to do
201 so by adding a function to this hook. The first function to return a
202 substitute command form is the one used. Each function is passed the
203 command's full argument list, which is a list of sexps (typically
204 forms or strings)."
205 :type 'hook
206 :group 'eshell-cmd)
208 (defcustom eshell-post-rewrite-command-hook nil
209 "A hook run after command rewriting is finished.
210 Each function is passed the symbol containing the rewritten command,
211 which may be modified directly. Any return value is ignored."
212 :type 'hook
213 :group 'eshell-cmd)
215 (defcustom eshell-complex-commands '("ls")
216 "A list of commands names or functions, that determine complexity.
217 That is, if a command is defined by a function named eshell/NAME,
218 and NAME is part of this list, it is invoked as a complex command.
219 Complex commands are always correct, but run much slower. If a
220 command works fine without being part of this list, then it doesn't
221 need to be.
223 If an entry is a function, it will be called with the name, and should
224 return non-nil if the command is complex."
225 :type '(repeat :tag "Commands"
226 (choice (string :tag "Name")
227 (function :tag "Predicate")))
228 :group 'eshell-cmd)
230 ;;; User Variables:
232 (defcustom eshell-cmd-load-hook nil
233 "A hook that gets run when `eshell-cmd' is loaded."
234 :version "24.1" ; removed eshell-cmd-initialize
235 :type 'hook
236 :group 'eshell-cmd)
238 (defcustom eshell-debug-command nil
239 "If non-nil, enable Eshell debugging code.
240 This is slow, and only useful for debugging problems with Eshell.
241 If you change this without using customize after Eshell has loaded,
242 you must re-load 'esh-cmd.el'."
243 :initialize 'custom-initialize-default
244 :set (lambda (symbol value)
245 (set symbol value)
246 (load-library "esh-cmd"))
247 :type 'boolean
248 :group 'eshell-cmd)
250 (defcustom eshell-deferrable-commands
251 '(eshell-named-command
252 eshell-lisp-command
253 eshell-process-identity)
254 "A list of functions which might return an asynchronous process.
255 If they return a process object, execution of the calling Eshell
256 command will wait for completion (in the background) before finishing
257 the command."
258 :type '(repeat function)
259 :group 'eshell-cmd)
261 (defcustom eshell-subcommand-bindings
262 '((eshell-in-subcommand-p t)
263 (default-directory default-directory)
264 (process-environment (eshell-copy-environment)))
265 "A list of `let' bindings for subcommand environments."
266 :type 'sexp
267 :group 'eshell-cmd)
269 (put 'risky-local-variable 'eshell-subcommand-bindings t)
271 (defvar eshell-ensure-newline-p nil
272 "If non-nil, ensure that a newline is emitted after a Lisp form.
273 This can be changed by Lisp forms that are evaluated from the Eshell
274 command line.")
276 ;;; Internal Variables:
278 (defvar eshell-current-command nil)
279 (defvar eshell-command-name nil)
280 (defvar eshell-command-arguments nil)
281 (defvar eshell-in-pipeline-p nil
282 "Internal Eshell variable, non-nil inside a pipeline.
283 Has the value 'first, 'last for the first/last commands in the pipeline,
284 otherwise t.")
285 (defvar eshell-in-subcommand-p nil)
286 (defvar eshell-last-arguments nil)
287 (defvar eshell-last-command-name nil)
288 (defvar eshell-last-async-proc nil
289 "When this foreground process completes, resume command evaluation.")
291 ;;; Functions:
293 (defsubst eshell-interactive-process ()
294 "Return currently running command process, if non-Lisp."
295 eshell-last-async-proc)
297 (defun eshell-cmd-initialize ()
298 "Initialize the Eshell command processing module."
299 (set (make-local-variable 'eshell-current-command) nil)
300 (set (make-local-variable 'eshell-command-name) nil)
301 (set (make-local-variable 'eshell-command-arguments) nil)
302 (set (make-local-variable 'eshell-last-arguments) nil)
303 (set (make-local-variable 'eshell-last-command-name) nil)
304 (set (make-local-variable 'eshell-last-async-proc) nil)
306 (add-hook 'eshell-kill-hook 'eshell-resume-command nil t)
308 ;; make sure that if a command is over, and no process is being
309 ;; waited for, that `eshell-current-command' is set to nil. This
310 ;; situation can occur, for example, if a Lisp function results in
311 ;; `debug' being called, and the user then types \\[top-level]
312 (add-hook 'eshell-post-command-hook
313 (function
314 (lambda ()
315 (setq eshell-current-command nil
316 eshell-last-async-proc nil))) nil t)
318 (add-hook 'eshell-parse-argument-hook
319 'eshell-parse-subcommand-argument nil t)
320 (add-hook 'eshell-parse-argument-hook
321 'eshell-parse-lisp-argument nil t)
323 (when (eshell-using-module 'eshell-cmpl)
324 (add-hook 'pcomplete-try-first-hook
325 'eshell-complete-lisp-symbols nil t)))
327 (defun eshell-complete-lisp-symbols ()
328 "If there is a user reference, complete it."
329 (let ((arg (pcomplete-actual-arg)))
330 (when (string-match (concat "\\`" eshell-lisp-regexp) arg)
331 (setq pcomplete-stub (substring arg (match-end 0))
332 pcomplete-last-completion-raw t)
333 (throw 'pcomplete-completions
334 (all-completions pcomplete-stub obarray 'boundp)))))
336 ;; Command parsing
338 (defun eshell-parse-command (command &optional args top-level)
339 "Parse the COMMAND, adding ARGS if given.
340 COMMAND can either be a string, or a cons cell demarcating a buffer
341 region. TOP-LEVEL, if non-nil, means that the outermost command (the
342 user's input command) is being parsed, and that pre and post command
343 hooks should be run before and after the command."
344 (let* (sep-terms
345 (terms
346 (append
347 (if (consp command)
348 (eshell-parse-arguments (car command) (cdr command))
349 (let ((here (point))
350 (inhibit-point-motion-hooks t))
351 (with-silent-modifications
352 ;; FIXME: Why not use a temporary buffer and avoid this
353 ;; "insert&delete" business? --Stef
354 (insert command)
355 (prog1
356 (eshell-parse-arguments here (point))
357 (delete-region here (point))))))
358 args))
359 (commands
360 (mapcar
361 (function
362 (lambda (cmd)
363 (setq cmd
364 (if (or (not (car sep-terms))
365 (string= (car sep-terms) ";"))
366 (eshell-parse-pipeline cmd (not (car sep-terms)))
367 `(eshell-do-subjob
368 (list ,(eshell-parse-pipeline cmd)))))
369 (setq sep-terms (cdr sep-terms))
370 (if eshell-in-pipeline-p
372 `(eshell-trap-errors ,cmd))))
373 (eshell-separate-commands terms "[&;]" nil 'sep-terms))))
374 (let ((cmd commands))
375 (while cmd
376 (if (cdr cmd)
377 (setcar cmd `(eshell-commands ,(car cmd))))
378 (setq cmd (cdr cmd))))
379 (setq commands
380 `(progn
381 ,@(if top-level
382 '((run-hooks 'eshell-pre-command-hook)))
383 ,@(if (not top-level)
384 commands
385 `((catch 'top-level (progn ,@commands))
386 (run-hooks 'eshell-post-command-hook)))))
387 (if top-level
388 `(eshell-commands ,commands)
389 commands)))
391 (defun eshell-debug-command (tag subform)
392 "Output a debugging message to '*eshell last cmd*'."
393 (let ((buf (get-buffer-create "*eshell last cmd*"))
394 (text (eshell-stringify eshell-current-command)))
395 (with-current-buffer buf
396 (if (not tag)
397 (erase-buffer)
398 (insert "\n\C-l\n" tag "\n\n" text
399 (if subform
400 (concat "\n\n" (eshell-stringify subform)) ""))))))
402 (defun eshell-debug-show-parsed-args (terms)
403 "Display parsed arguments in the debug buffer."
404 (ignore
405 (if eshell-debug-command
406 (eshell-debug-command "parsed arguments" terms))))
408 (defun eshell-no-command-conversion (terms)
409 "Don't convert the command argument."
410 (ignore
411 (if (and (listp (car terms))
412 (eq (caar terms) 'eshell-convert))
413 (setcar terms (cadr (car terms))))))
415 (defun eshell-subcommand-arg-values (terms)
416 "Convert subcommand arguments {x} to ${x}, in order to take their values."
417 (setq terms (cdr terms)) ; skip command argument
418 (while terms
419 (if (and (listp (car terms))
420 (eq (caar terms) 'eshell-as-subcommand))
421 (setcar terms `(eshell-convert
422 (eshell-command-to-value ,(car terms)))))
423 (setq terms (cdr terms))))
425 (defun eshell-rewrite-sexp-command (terms)
426 "Rewrite a sexp in initial position, such as '(+ 1 2)'."
427 ;; this occurs when a Lisp expression is in first position
428 (if (and (listp (car terms))
429 (eq (caar terms) 'eshell-command-to-value))
430 (car (cdar terms))))
432 (defun eshell-rewrite-initial-subcommand (terms)
433 "Rewrite a subcommand in initial position, such as '{+ 1 2}'."
434 (if (and (listp (car terms))
435 (eq (caar terms) 'eshell-as-subcommand))
436 (car terms)))
438 (defun eshell-rewrite-named-command (terms)
439 "If no other rewriting rule transforms TERMS, assume a named command."
440 (let ((sym (if eshell-in-pipeline-p
441 'eshell-named-command*
442 'eshell-named-command))
443 (cmd (car terms))
444 (args (cdr terms)))
445 (if args
446 (list sym cmd `(list ,@(cdr terms)))
447 (list sym cmd))))
449 (defvar eshell-command-body)
450 (defvar eshell-test-body)
452 (defsubst eshell-invokify-arg (arg &optional share-output silent)
453 "Change ARG so it can be invoked from a structured command.
455 SHARE-OUTPUT, if non-nil, means this invocation should share the
456 current output stream, which is separately redirectable. SILENT
457 means the user and/or any redirections shouldn't see any output
458 from this command. If both SHARE-OUTPUT and SILENT are non-nil,
459 the second is ignored."
460 ;; something that begins with `eshell-convert' means that it
461 ;; intends to return a Lisp value. We want to get past this,
462 ;; but if it's not _actually_ a value interpolation -- in which
463 ;; we leave it alone. In fact, the only time we muck with it
464 ;; is in the case of a {subcommand} that has been turned into
465 ;; the interpolation, ${subcommand}, by the parser because it
466 ;; didn't know better.
467 (if (and (listp arg)
468 (eq (car arg) 'eshell-convert)
469 (eq (car (cadr arg)) 'eshell-command-to-value))
470 (if share-output
471 (cadr (cadr arg))
472 `(eshell-commands ,(cadr (cadr arg)) ,silent))
473 arg))
475 (defvar eshell-last-command-status) ;Define in esh-io.el.
477 (defun eshell-rewrite-for-command (terms)
478 "Rewrite a `for' command into its equivalent Eshell command form.
479 Because the implementation of `for' relies upon conditional evaluation
480 of its argument (i.e., use of a Lisp special form), it must be
481 implemented via rewriting, rather than as a function."
482 (if (and (equal (car terms) "for")
483 (equal (nth 2 terms) "in"))
484 (let ((body (car (last terms))))
485 (setcdr (last terms 2) nil)
486 `(let ((for-items
487 (copy-tree
488 (append
489 ,@(mapcar
490 (lambda (elem)
491 (if (listp elem)
492 elem
493 `(list ,elem)))
494 (cdr (cddr terms))))))
495 (eshell-command-body '(nil))
496 (eshell-test-body '(nil)))
497 (while (car for-items)
498 (let ((,(intern (cadr terms)) (car for-items)))
499 (eshell-protect
500 ,(eshell-invokify-arg body t)))
501 (setcar for-items (cadr for-items))
502 (setcdr for-items (cddr for-items)))
503 (eshell-close-handles
504 eshell-last-command-status
505 (list 'quote eshell-last-command-result))))))
507 (defun eshell-structure-basic-command (func names keyword test body
508 &optional else vocal-test)
509 "With TERMS, KEYWORD, and two NAMES, structure a basic command.
510 The first of NAMES should be the positive form, and the second the
511 negative. It's not likely that users should ever need to call this
512 function.
514 If VOCAL-TEST is non-nil, it means output from the test should be
515 shown, as well as output from the body."
516 ;; If the test form begins with `eshell-convert', it means
517 ;; something data-wise will be returned, and we should let
518 ;; that determine the truth of the statement.
519 (unless (eq (car test) 'eshell-convert)
520 (setq test
521 `(progn ,test
522 (eshell-exit-success-p))))
524 ;; should we reverse the sense of the test? This depends
525 ;; on the `names' parameter. If it's the symbol nil, yes.
526 ;; Otherwise, it can be a pair of strings; if the keyword
527 ;; we're using matches the second member of that pair (a
528 ;; list), we should reverse it.
529 (if (or (eq names nil)
530 (and (listp names)
531 (string= keyword (cadr names))))
532 (setq test `(not ,test)))
534 ;; finally, create the form that represents this structured
535 ;; command
536 `(let ((eshell-command-body '(nil))
537 (eshell-test-body '(nil)))
538 (,func ,test ,body ,else)
539 (eshell-close-handles
540 eshell-last-command-status
541 (list 'quote eshell-last-command-result))))
543 (defun eshell-rewrite-while-command (terms)
544 "Rewrite a `while' command into its equivalent Eshell command form.
545 Because the implementation of `while' relies upon conditional
546 evaluation of its argument (i.e., use of a Lisp special form), it
547 must be implemented via rewriting, rather than as a function."
548 (if (and (stringp (car terms))
549 (member (car terms) '("while" "until")))
550 (eshell-structure-basic-command
551 'while '("while" "until") (car terms)
552 (eshell-invokify-arg (cadr terms) nil t)
553 `(eshell-protect
554 ,(eshell-invokify-arg (car (last terms)) t)))))
556 (defun eshell-rewrite-if-command (terms)
557 "Rewrite an `if' command into its equivalent Eshell command form.
558 Because the implementation of `if' relies upon conditional
559 evaluation of its argument (i.e., use of a Lisp special form), it
560 must be implemented via rewriting, rather than as a function."
561 (if (and (stringp (car terms))
562 (member (car terms) '("if" "unless")))
563 (eshell-structure-basic-command
564 'if '("if" "unless") (car terms)
565 (eshell-invokify-arg (cadr terms) nil t)
566 `(eshell-protect
567 ,(eshell-invokify-arg (car (last terms (if (= (length terms) 4) 2)))
569 (if (= (length terms) 4)
570 `(eshell-protect
571 ,(eshell-invokify-arg (car (last terms)))) t))))
573 (defvar eshell-last-command-result) ;Defined in esh-io.el.
575 (defun eshell-exit-success-p ()
576 "Return non-nil if the last command was \"successful\".
577 For a bit of Lisp code, this means a return value of non-nil.
578 For an external command, it means an exit code of 0."
579 (if (save-match-data
580 (string-match "#<\\(Lisp object\\|function .*\\)>"
581 eshell-last-command-name))
582 eshell-last-command-result
583 (= eshell-last-command-status 0)))
585 (defun eshell-parse-pipeline (terms &optional final-p)
586 "Parse a pipeline from TERMS, return the appropriate Lisp forms."
587 (let* (sep-terms
588 (bigpieces (eshell-separate-commands terms "\\(&&\\|||\\)"
589 nil 'sep-terms))
590 (bp bigpieces)
591 (results (list t))
592 final)
593 (while bp
594 (let ((subterms (car bp)))
595 (let* ((pieces (eshell-separate-commands subterms "|"))
596 (p pieces))
597 (while p
598 (let ((cmd (car p)))
599 (run-hook-with-args 'eshell-pre-rewrite-command-hook cmd)
600 (setq cmd (run-hook-with-args-until-success
601 'eshell-rewrite-command-hook cmd))
602 (run-hook-with-args 'eshell-post-rewrite-command-hook 'cmd)
603 (setcar p cmd))
604 (setq p (cdr p)))
605 (nconc results
606 (list
607 (if (<= (length pieces) 1)
608 (car pieces)
609 (cl-assert (not eshell-in-pipeline-p))
610 `(eshell-execute-pipeline (quote ,pieces))))))
611 (setq bp (cdr bp))))
612 ;; `results' might be empty; this happens in the case of
613 ;; multi-line input
614 (setq results (cdr results)
615 results (nreverse results)
616 final (car results)
617 results (cdr results)
618 sep-terms (nreverse sep-terms))
619 (while results
620 (cl-assert (car sep-terms))
621 (setq final (eshell-structure-basic-command
622 'if (string= (car sep-terms) "&&") "if"
623 `(eshell-protect ,(car results))
624 `(eshell-protect ,final)
625 nil t)
626 results (cdr results)
627 sep-terms (cdr sep-terms)))
628 final))
630 (defun eshell-parse-subcommand-argument ()
631 "Parse a subcommand argument of the form '{command}'."
632 (if (and (not eshell-current-argument)
633 (not eshell-current-quoted)
634 (eq (char-after) ?\{)
635 (or (= (point-max) (1+ (point)))
636 (not (eq (char-after (1+ (point))) ?\}))))
637 (let ((end (eshell-find-delimiter ?\{ ?\})))
638 (if (not end)
639 (throw 'eshell-incomplete ?\{)
640 (when (eshell-arg-delimiter (1+ end))
641 (prog1
642 `(eshell-as-subcommand
643 ,(eshell-parse-command (cons (1+ (point)) end)))
644 (goto-char (1+ end))))))))
646 (defun eshell-parse-lisp-argument ()
647 "Parse a Lisp expression which is specified as an argument."
648 (if (and (not eshell-current-argument)
649 (not eshell-current-quoted)
650 (looking-at eshell-lisp-regexp))
651 (let* ((here (point))
652 (obj
653 (condition-case err
654 (read (current-buffer))
655 (end-of-file
656 (throw 'eshell-incomplete ?\()))))
657 (if (eshell-arg-delimiter)
658 `(eshell-command-to-value
659 (eshell-lisp-command (quote ,obj)))
660 (ignore (goto-char here))))))
662 (defun eshell-separate-commands (terms separator &optional
663 reversed last-terms-sym)
664 "Separate TERMS using SEPARATOR.
665 If REVERSED is non-nil, the list of separated term groups will be
666 returned in reverse order. If LAST-TERMS-SYM is a symbol, its value
667 will be set to a list of all the separator operators found (or '(list
668 nil)' if none)."
669 (let ((sub-terms (list t))
670 (eshell-sep-terms (list t))
671 subchains)
672 (while terms
673 (if (and (consp (car terms))
674 (eq (caar terms) 'eshell-operator)
675 (string-match (concat "^" separator "$")
676 (nth 1 (car terms))))
677 (progn
678 (nconc eshell-sep-terms (list (nth 1 (car terms))))
679 (setq subchains (cons (cdr sub-terms) subchains)
680 sub-terms (list t)))
681 (nconc sub-terms (list (car terms))))
682 (setq terms (cdr terms)))
683 (if (> (length sub-terms) 1)
684 (setq subchains (cons (cdr sub-terms) subchains)))
685 (if reversed
686 (progn
687 (if last-terms-sym
688 (set last-terms-sym (reverse (cdr eshell-sep-terms))))
689 subchains) ; already reversed
690 (if last-terms-sym
691 (set last-terms-sym (cdr eshell-sep-terms)))
692 (nreverse subchains))))
694 ;;_* Command evaluation macros
696 ;; The structure of the following macros is very important to
697 ;; `eshell-do-eval' [Iterative evaluation]:
699 ;; @ Don't use forms that conditionally evaluate their arguments, such
700 ;; as `setq', `if', `while', `let*', etc. The only special forms
701 ;; that can be used are `let', `condition-case' and
702 ;; `unwind-protect'.
704 ;; @ The main body of a `let' can contain only one form. Use `progn'
705 ;; if necessary.
707 ;; @ The two `special' variables are `eshell-current-handles' and
708 ;; `eshell-current-subjob-p'. Bind them locally with a `let' if you
709 ;; need to change them. Change them directly only if your intention
710 ;; is to change the calling environment.
712 (defmacro eshell-do-subjob (object)
713 "Evaluate a command OBJECT as a subjob.
714 We indicate that the process was run in the background by returning it
715 ensconced in a list."
716 `(let ((eshell-current-subjob-p t))
717 ,object))
719 (defmacro eshell-commands (object &optional silent)
720 "Place a valid set of handles, and context, around command OBJECT."
721 `(let ((eshell-current-handles
722 (eshell-create-handles ,(not silent) 'append))
723 eshell-current-subjob-p)
724 ,object))
726 (defmacro eshell-trap-errors (object)
727 "Trap any errors that occur, so they are not entirely fatal.
728 Also, the variable `eshell-this-command-hook' is available for the
729 duration of OBJECT's evaluation. Note that functions should be added
730 to this hook using `nconc', and *not* `add-hook'.
732 Someday, when Scheme will become the dominant Emacs language, all of
733 this grossness will be made to disappear by using `call/cc'..."
734 `(let ((eshell-this-command-hook '(ignore)))
735 (eshell-condition-case err
736 (prog1
737 ,object
738 (run-hooks 'eshell-this-command-hook))
739 (error
740 (run-hooks 'eshell-this-command-hook)
741 (eshell-errorn (error-message-string err))
742 (eshell-close-handles 1)))))
744 (defvar eshell-output-handle) ;Defined in esh-io.el.
745 (defvar eshell-error-handle) ;Defined in esh-io.el.
747 (defmacro eshell-copy-handles (object)
748 "Duplicate current I/O handles, so OBJECT works with its own copy."
749 `(let ((eshell-current-handles
750 (eshell-create-handles
751 (car (aref eshell-current-handles
752 eshell-output-handle)) nil
753 (car (aref eshell-current-handles
754 eshell-error-handle)) nil)))
755 ,object))
757 (defmacro eshell-protect (object)
758 "Protect I/O handles, so they aren't get closed after eval'ing OBJECT."
759 `(progn
760 (eshell-protect-handles eshell-current-handles)
761 ,object))
763 (defmacro eshell-do-pipelines (pipeline &optional notfirst)
764 "Execute the commands in PIPELINE, connecting each to one another.
765 This macro calls itself recursively, with NOTFIRST non-nil."
766 (when (setq pipeline (cadr pipeline))
767 `(eshell-copy-handles
768 (progn
769 ,(when (cdr pipeline)
770 `(let ((nextproc
771 (eshell-do-pipelines (quote ,(cdr pipeline)) t)))
772 (eshell-set-output-handle ,eshell-output-handle
773 'append nextproc)
774 (eshell-set-output-handle ,eshell-error-handle
775 'append nextproc)
776 (setq tailproc (or tailproc nextproc))))
777 ,(let ((head (car pipeline)))
778 (if (memq (car head) '(let progn))
779 (setq head (car (last head))))
780 (when (memq (car head) eshell-deferrable-commands)
781 (ignore
782 (setcar head
783 (intern-soft
784 (concat (symbol-name (car head)) "*"))))))
785 ;; First and last elements in a pipeline may need special treatment.
786 ;; (Currently only eshell-ls-files uses 'last.)
787 ;; Affects process-connection-type in eshell-gather-process-output.
788 (let ((eshell-in-pipeline-p
789 ,(cond ((not notfirst) (quote 'first))
790 ((cdr pipeline) t)
791 (t (quote 'last)))))
792 ,(car pipeline))))))
794 (defmacro eshell-do-pipelines-synchronously (pipeline)
795 "Execute the commands in PIPELINE in sequence synchronously.
796 Output of each command is passed as input to the next one in the pipeline.
797 This is used on systems where `start-process' is not supported."
798 (when (setq pipeline (cadr pipeline))
799 `(progn
800 ,(when (cdr pipeline)
801 `(let ((output-marker ,(point-marker)))
802 (eshell-set-output-handle ,eshell-output-handle
803 'append output-marker)
804 (eshell-set-output-handle ,eshell-error-handle
805 'append output-marker)))
806 ,(let ((head (car pipeline)))
807 (if (memq (car head) '(let progn))
808 (setq head (car (last head))))
809 ;; FIXME: is deferrable significant here?
810 (when (memq (car head) eshell-deferrable-commands)
811 (ignore
812 (setcar head
813 (intern-soft
814 (concat (symbol-name (car head)) "*"))))))
815 ;; The last process in the pipe should get its handles
816 ;; redirected as we found them before running the pipe.
817 ,(if (null (cdr pipeline))
818 `(progn
819 (setq eshell-current-handles tail-handles)
820 (setq eshell-in-pipeline-p nil)))
821 (let ((result ,(car pipeline)))
822 ;; tailproc gets the result of the last successful process in
823 ;; the pipeline.
824 (setq tailproc (or result tailproc))
825 ,(if (cdr pipeline)
826 `(eshell-do-pipelines-synchronously (quote ,(cdr pipeline))))
827 result))))
829 (defalias 'eshell-process-identity 'identity)
831 (defmacro eshell-execute-pipeline (pipeline)
832 "Execute the commands in PIPELINE, connecting each to one another."
833 `(let ((eshell-in-pipeline-p t) tailproc)
834 (progn
835 ,(if (fboundp 'start-process)
836 `(eshell-do-pipelines ,pipeline)
837 `(let ((tail-handles (eshell-create-handles
838 (car (aref eshell-current-handles
839 ,eshell-output-handle)) nil
840 (car (aref eshell-current-handles
841 ,eshell-error-handle)) nil)))
842 (eshell-do-pipelines-synchronously ,pipeline)))
843 (eshell-process-identity tailproc))))
845 (defmacro eshell-as-subcommand (command)
846 "Execute COMMAND using a temp buffer.
847 This is used so that certain Lisp commands, such as `cd', when
848 executed in a subshell, do not disturb the environment of the main
849 Eshell buffer."
850 `(let ,eshell-subcommand-bindings
851 ,command))
853 (defmacro eshell-do-command-to-value (object)
854 "Run a subcommand prepared by `eshell-command-to-value'.
855 This avoids the need to use `let*'."
856 `(let ((eshell-current-handles
857 (eshell-create-handles value 'overwrite)))
858 (progn
859 ,object
860 (symbol-value value))))
862 (defmacro eshell-command-to-value (object)
863 "Run OBJECT synchronously, returning its result as a string.
864 Returns a string comprising the output from the command."
865 `(let ((value (make-symbol "eshell-temp")))
866 (eshell-do-command-to-value ,object)))
868 ;;;_* Iterative evaluation
870 ;; Eshell runs all of its external commands asynchronously, so that
871 ;; Emacs is not blocked while the operation is being performed.
872 ;; However, this introduces certain synchronization difficulties,
873 ;; since the Lisp code, once it returns, will not "go back" to finish
874 ;; executing the commands which haven't yet been started.
876 ;; What Eshell does to work around this problem (basically, the lack
877 ;; of threads in Lisp), is that it evaluates the command sequence
878 ;; iteratively. Whenever an asynchronous process is begun, evaluation
879 ;; terminates and control is given back to Emacs. When that process
880 ;; finishes, it will resume the evaluation using the remainder of the
881 ;; command tree.
883 (defun eshell/eshell-debug (&rest args)
884 "A command for toggling certain debug variables."
885 (ignore
886 (cond
887 ((not args)
888 (if eshell-handle-errors
889 (eshell-print "errors\n"))
890 (if eshell-debug-command
891 (eshell-print "commands\n")))
892 ((member (car args) '("-h" "--help"))
893 (eshell-print "usage: eshell-debug [kinds]
895 This command is used to aid in debugging problems related to Eshell
896 itself. It is not useful for anything else. The recognized `kinds'
897 at the moment are:
899 errors stops Eshell from trapping errors
900 commands shows command execution progress in `*eshell last cmd*'
903 (while args
904 (cond
905 ((string= (car args) "errors")
906 (setq eshell-handle-errors (not eshell-handle-errors)))
907 ((string= (car args) "commands")
908 (setq eshell-debug-command (not eshell-debug-command))))
909 (setq args (cdr args)))))))
911 (defun pcomplete/eshell-mode/eshell-debug ()
912 "Completion for the `debug' command."
913 (while (pcomplete-here '("errors" "commands"))))
915 (defun eshell-invoke-directly (command input)
916 (let ((base (cadr (nth 2 (nth 2 (cadr command))))) name)
917 (if (and (eq (car base) 'eshell-trap-errors)
918 (eq (car (cadr base)) 'eshell-named-command))
919 (setq name (cadr (cadr base))))
920 (and name (stringp name)
921 (not (member name eshell-complex-commands))
922 (catch 'simple
923 (progn
924 (dolist (pred eshell-complex-commands)
925 (if (and (functionp pred)
926 (funcall pred name))
927 (throw 'simple nil)))
929 (fboundp (intern-soft (concat "eshell/" name))))))
931 (defun eshell-eval-command (command &optional input)
932 "Evaluate the given COMMAND iteratively."
933 (if eshell-current-command
934 ;; we can just stick the new command at the end of the current
935 ;; one, and everything will happen as it should
936 (setcdr (last (cdr eshell-current-command))
937 (list `(let ((here (and (eobp) (point))))
938 ,(and input
939 `(insert-and-inherit ,(concat input "\n")))
940 (if here
941 (eshell-update-markers here))
942 (eshell-do-eval ',command))))
943 (and eshell-debug-command
944 (with-current-buffer (get-buffer-create "*eshell last cmd*")
945 (erase-buffer)
946 (insert "command: \"" input "\"\n")))
947 (setq eshell-current-command command)
948 (let ((delim (catch 'eshell-incomplete
949 (eshell-resume-eval))))
950 ;; On systems that don't support async subprocesses, eshell-resume
951 ;; can return t. Don't treat that as an error.
952 (if (listp delim)
953 (setq delim (car delim)))
954 (if (and delim (not (eq delim t)))
955 (error "Unmatched delimiter: %c" delim)))))
957 (defun eshell-resume-command (proc status)
958 "Resume the current command when a process ends."
959 (when proc
960 (unless (or (not (stringp status))
961 (string= "stopped" status)
962 (string-match eshell-reset-signals status))
963 (if (eq proc (eshell-interactive-process))
964 (eshell-resume-eval)))))
966 (defun eshell-resume-eval ()
967 "Destructively evaluate a form which may need to be deferred."
968 (eshell-condition-case err
969 (progn
970 (setq eshell-last-async-proc nil)
971 (when eshell-current-command
972 (let* (retval
973 (proc (catch 'eshell-defer
974 (ignore
975 (setq retval
976 (eshell-do-eval
977 eshell-current-command))))))
978 (if (eshell-processp proc)
979 (ignore (setq eshell-last-async-proc proc))
980 (cadr retval)))))
981 (error
982 (error (error-message-string err)))))
984 (defmacro eshell-manipulate (tag &rest commands)
985 "Manipulate a COMMAND form, with TAG as a debug identifier."
986 (declare (indent 1))
987 ;; Check `bound'ness since at compile time the code until here has not
988 ;; executed yet.
989 (if (not (and (boundp 'eshell-debug-command) eshell-debug-command))
990 `(progn ,@commands)
991 `(progn
992 (eshell-debug-command ,(eval tag) form)
993 ,@commands
994 (eshell-debug-command ,(concat "done " (eval tag)) form))))
996 (defsubst eshell-macrop (object)
997 "Return t if OBJECT is a macro or nil otherwise."
998 (and (symbolp object) (fboundp object)
999 (setq object (indirect-function object))
1000 (listp object)
1001 (eq 'macro (car object))
1002 (functionp (cdr object))))
1004 (defun eshell-do-eval (form &optional synchronous-p)
1005 "Evaluate form, simplifying it as we go.
1006 Unless SYNCHRONOUS-P is non-nil, throws `eshell-defer' if it needs to
1007 be finished later after the completion of an asynchronous subprocess."
1008 (cond
1009 ((not (listp form))
1010 (list 'quote (eval form)))
1011 ((memq (car form) '(quote function))
1012 form)
1014 ;; skip past the call to `eshell-do-eval'
1015 (when (eq (car form) 'eshell-do-eval)
1016 (setq form (cadr (cadr form))))
1017 ;; expand any macros directly into the form. This is done so that
1018 ;; we can modify any `let' forms to evaluate only once.
1019 (if (eshell-macrop (car form))
1020 (let ((exp (eshell-copy-tree (macroexpand form))))
1021 (eshell-manipulate (format "expanding macro `%s'"
1022 (symbol-name (car form)))
1023 (setcar form (car exp))
1024 (setcdr form (cdr exp)))))
1025 (let ((args (cdr form)))
1026 (cond
1027 ((eq (car form) 'while)
1028 ;; `eshell-copy-tree' is needed here so that the test argument
1029 ;; doesn't get modified and thus always yield the same result.
1030 (when (car eshell-command-body)
1031 (cl-assert (not synchronous-p))
1032 (eshell-do-eval (car eshell-command-body))
1033 (setcar eshell-command-body nil)
1034 (setcar eshell-test-body nil))
1035 (unless (car eshell-test-body)
1036 (setcar eshell-test-body (eshell-copy-tree (car args))))
1037 (while (cadr (eshell-do-eval (car eshell-test-body)))
1038 (setcar eshell-command-body
1039 (if (cddr args)
1040 `(progn ,@(eshell-copy-tree (cdr args)))
1041 (eshell-copy-tree (cadr args))))
1042 (eshell-do-eval (car eshell-command-body) synchronous-p)
1043 (setcar eshell-command-body nil)
1044 (setcar eshell-test-body (eshell-copy-tree (car args))))
1045 (setcar eshell-command-body nil))
1046 ((eq (car form) 'if)
1047 ;; `eshell-copy-tree' is needed here so that the test argument
1048 ;; doesn't get modified and thus always yield the same result.
1049 (if (car eshell-command-body)
1050 (progn
1051 (cl-assert (not synchronous-p))
1052 (eshell-do-eval (car eshell-command-body)))
1053 (unless (car eshell-test-body)
1054 (setcar eshell-test-body (eshell-copy-tree (car args))))
1055 (setcar eshell-command-body
1056 (eshell-copy-tree
1057 (if (cadr (eshell-do-eval (car eshell-test-body)))
1058 (cadr args)
1059 (car (cddr args)))))
1060 (eshell-do-eval (car eshell-command-body) synchronous-p))
1061 (setcar eshell-command-body nil)
1062 (setcar eshell-test-body nil))
1063 ((eq (car form) 'setcar)
1064 (setcar (cdr args) (eshell-do-eval (cadr args) synchronous-p))
1065 (eval form))
1066 ((eq (car form) 'setcdr)
1067 (setcar (cdr args) (eshell-do-eval (cadr args) synchronous-p))
1068 (eval form))
1069 ((memq (car form) '(let catch condition-case unwind-protect))
1070 ;; `let', `condition-case' and `unwind-protect' have to be
1071 ;; handled specially, because we only want to call
1072 ;; `eshell-do-eval' on their first form.
1074 ;; NOTE: This requires obedience by all forms which this
1075 ;; function might encounter, that they do not contain
1076 ;; other special forms.
1077 (if (and (eq (car form) 'let)
1078 (not (eq (car (cadr args)) 'eshell-do-eval)))
1079 (eshell-manipulate "evaluating let args"
1080 (dolist (letarg (car args))
1081 (if (and (listp letarg)
1082 (not (eq (cadr letarg) 'quote)))
1083 (setcdr letarg
1084 (list (eshell-do-eval
1085 (cadr letarg) synchronous-p)))))))
1086 (unless (eq (car form) 'unwind-protect)
1087 (setq args (cdr args)))
1088 (unless (eq (caar args) 'eshell-do-eval)
1089 (eshell-manipulate "handling special form"
1090 (setcar args `(eshell-do-eval ',(car args) ,synchronous-p))))
1091 (eval form))
1092 ((eq (car form) 'setq)
1093 (if (cddr args) (error "Unsupported form (setq X1 E1 X2 E2..)"))
1094 (eshell-manipulate "evaluating arguments to setq"
1095 (setcar (cdr args) (eshell-do-eval (cadr args) synchronous-p)))
1096 (list 'quote (eval form)))
1098 (if (and args (not (memq (car form) '(run-hooks))))
1099 (eshell-manipulate
1100 (format "evaluating arguments to `%s'"
1101 (symbol-name (car form)))
1102 (while args
1103 (setcar args (eshell-do-eval (car args) synchronous-p))
1104 (setq args (cdr args)))))
1105 (cond
1106 ((eq (car form) 'progn)
1107 (car (last form)))
1108 ((eq (car form) 'prog1)
1109 (cadr form))
1111 ;; If a command desire to replace its execution form with
1112 ;; another command form, all it needs to do is throw the new
1113 ;; form using the exception tag `eshell-replace-command'.
1114 ;; For example, let's say that the form currently being
1115 ;; eval'd is:
1117 ;; (eshell-named-command "hello")
1119 ;; Now, let's assume the 'hello' command is an Eshell alias,
1120 ;; the definition of which yields the command:
1122 ;; (eshell-named-command "echo" (list "Hello" "world"))
1124 ;; What the alias code would like to do is simply substitute
1125 ;; the alias form for the original form. To accomplish
1126 ;; this, all it needs to do is to throw the substitution
1127 ;; form with the `eshell-replace-command' tag, and the form
1128 ;; will be replaced within the current command, and
1129 ;; execution will then resume (iteratively) as before.
1130 ;; Thus, aliases can even contain references to asynchronous
1131 ;; sub-commands, and things will still work out as they
1132 ;; should.
1133 (let* (result
1134 (new-form
1135 (catch 'eshell-replace-command
1136 (ignore
1137 (setq result (eval form))))))
1138 (if new-form
1139 (progn
1140 (eshell-manipulate "substituting replacement form"
1141 (setcar form (car new-form))
1142 (setcdr form (cdr new-form)))
1143 (eshell-do-eval form synchronous-p))
1144 (if (and (memq (car form) eshell-deferrable-commands)
1145 (not eshell-current-subjob-p)
1146 result
1147 (eshell-processp result))
1148 (if synchronous-p
1149 (eshell/wait result)
1150 (eshell-manipulate "inserting ignore form"
1151 (setcar form 'ignore)
1152 (setcdr form nil))
1153 (throw 'eshell-defer result))
1154 (list 'quote result))))))))))))
1156 ;; command invocation
1158 (defun eshell/which (command &rest names)
1159 "Identify the COMMAND, and where it is located."
1160 (dolist (name (cons command names))
1161 (let (program alias direct)
1162 (if (eq (aref name 0) eshell-explicit-command-char)
1163 (setq name (substring name 1)
1164 direct t))
1165 (if (and (not direct)
1166 (eshell-using-module 'eshell-alias)
1167 (setq alias
1168 (funcall (symbol-function 'eshell-lookup-alias)
1169 name)))
1170 (setq program
1171 (concat name " is an alias, defined as \""
1172 (cadr alias) "\"")))
1173 (unless program
1174 (setq program (eshell-search-path name))
1175 (let* ((esym (eshell-find-alias-function name))
1176 (sym (or esym (intern-soft name))))
1177 (if (and (or esym (and sym (fboundp sym)))
1178 (or eshell-prefer-lisp-functions (not direct)))
1179 (let ((desc (let ((inhibit-redisplay t))
1180 (save-window-excursion
1181 (prog1
1182 (describe-function sym)
1183 (message nil))))))
1184 (setq desc (if desc (substring desc 0
1185 (1- (or (string-match "\n" desc)
1186 (length desc))))
1187 ;; This should not happen.
1188 (format "%s is defined, \
1189 but no documentation was found" name)))
1190 (if (buffer-live-p (get-buffer "*Help*"))
1191 (kill-buffer "*Help*"))
1192 (setq program (or desc name))))))
1193 (if (not program)
1194 (eshell-error (format "which: no %s in (%s)\n"
1195 name (getenv "PATH")))
1196 (eshell-printn program)))))
1198 (put 'eshell/which 'eshell-no-numeric-conversions t)
1200 (defun eshell-named-command (command &optional args)
1201 "Insert output from a plain COMMAND, using ARGS.
1202 COMMAND may result in an alias being executed, or a plain command."
1203 (setq eshell-last-arguments args
1204 eshell-last-command-name (eshell-stringify command))
1205 (run-hook-with-args 'eshell-prepare-command-hook)
1206 (cl-assert (stringp eshell-last-command-name))
1207 (if eshell-last-command-name
1208 (or (run-hook-with-args-until-success
1209 'eshell-named-command-hook eshell-last-command-name
1210 eshell-last-arguments)
1211 (eshell-plain-command eshell-last-command-name
1212 eshell-last-arguments))))
1214 (defalias 'eshell-named-command* 'eshell-named-command)
1216 (defun eshell-find-alias-function (name)
1217 "Check whether a function called `eshell/NAME' exists."
1218 (let* ((sym (intern-soft (concat "eshell/" name)))
1219 (file (symbol-file sym 'defun)))
1220 ;; If the function exists, but is defined in an eshell module
1221 ;; that's not currently enabled, don't report it as found.
1222 (if (and file
1223 (setq file (file-name-base file))
1224 (string-match "\\`\\(em\\|esh\\)-\\([[:alnum:]]+\\)\\'" file))
1225 (let ((module-sym
1226 (intern (concat "eshell-" (match-string 2 file)))))
1227 (if (and (functionp sym)
1228 (or (null module-sym)
1229 (eshell-using-module module-sym)
1230 (memq module-sym (eshell-subgroups 'eshell))))
1231 sym))
1232 ;; Otherwise, if it's bound, return it.
1233 (if (functionp sym)
1234 sym))))
1236 (defun eshell-plain-command (command args)
1237 "Insert output from a plain COMMAND, using ARGS.
1238 COMMAND may result in either a Lisp function being executed by name,
1239 or an external command."
1240 (let* ((esym (eshell-find-alias-function command))
1241 (sym (or esym (intern-soft command))))
1242 (if (and sym (fboundp sym)
1243 (or esym eshell-prefer-lisp-functions
1244 (not (eshell-search-path command))))
1245 (eshell-lisp-command sym args)
1246 (eshell-external-command command args))))
1248 (defun eshell-exec-lisp (printer errprint func-or-form args form-p)
1249 "Execute a lisp FUNC-OR-FORM, maybe passing ARGS.
1250 PRINTER and ERRPRINT are functions to use for printing regular
1251 messages, and errors. FORM-P should be non-nil if FUNC-OR-FORM
1252 represent a lisp form; ARGS will be ignored in that case."
1253 (eshell-condition-case err
1254 (let ((result
1255 (save-current-buffer
1256 (if form-p
1257 (eval func-or-form)
1258 (apply func-or-form args)))))
1259 (and result (funcall printer result))
1260 result)
1261 (error
1262 (let ((msg (error-message-string err)))
1263 (if (and (not form-p)
1264 (string-match "^Wrong number of arguments" msg)
1265 (fboundp 'eldoc-get-fnsym-args-string))
1266 (let ((func-doc (eldoc-get-fnsym-args-string func-or-form)))
1267 (setq msg (format "usage: %s" func-doc))))
1268 (funcall errprint msg))
1269 nil)))
1271 (defsubst eshell-apply* (printer errprint func args)
1272 "Call FUNC, with ARGS, trapping errors and return them as output.
1273 PRINTER and ERRPRINT are functions to use for printing regular
1274 messages, and errors."
1275 (eshell-exec-lisp printer errprint func args nil))
1277 (defsubst eshell-funcall* (printer errprint func &rest args)
1278 "Call FUNC, with ARGS, trapping errors and return them as output."
1279 (eshell-apply* printer errprint func args))
1281 (defsubst eshell-eval* (printer errprint form)
1282 "Evaluate FORM, trapping errors and returning them."
1283 (eshell-exec-lisp printer errprint form nil t))
1285 (defsubst eshell-apply (func args)
1286 "Call FUNC, with ARGS, trapping errors and return them as output.
1287 PRINTER and ERRPRINT are functions to use for printing regular
1288 messages, and errors."
1289 (eshell-apply* 'eshell-print 'eshell-error func args))
1291 (defsubst eshell-funcall (func &rest args)
1292 "Call FUNC, with ARGS, trapping errors and return them as output."
1293 (eshell-apply func args))
1295 (defsubst eshell-eval (form)
1296 "Evaluate FORM, trapping errors and returning them."
1297 (eshell-eval* 'eshell-print 'eshell-error form))
1299 (defsubst eshell-applyn (func args)
1300 "Call FUNC, with ARGS, trapping errors and return them as output.
1301 PRINTER and ERRPRINT are functions to use for printing regular
1302 messages, and errors."
1303 (eshell-apply* 'eshell-printn 'eshell-errorn func args))
1305 (defsubst eshell-funcalln (func &rest args)
1306 "Call FUNC, with ARGS, trapping errors and return them as output."
1307 (eshell-applyn func args))
1309 (defsubst eshell-evaln (form)
1310 "Evaluate FORM, trapping errors and returning them."
1311 (eshell-eval* 'eshell-printn 'eshell-errorn form))
1313 (defvar eshell-last-output-end) ;Defined in esh-mode.el.
1315 (defun eshell-lisp-command (object &optional args)
1316 "Insert Lisp OBJECT, using ARGS if a function."
1317 (catch 'eshell-external ; deferred to an external command
1318 (let* ((eshell-ensure-newline-p (eshell-interactive-output-p))
1319 (result
1320 (if (functionp object)
1321 (progn
1322 (setq eshell-last-arguments args
1323 eshell-last-command-name
1324 (concat "#<function " (symbol-name object) ">"))
1325 ;; if any of the arguments are flagged as numbers
1326 ;; waiting for conversion, convert them now
1327 (unless (get object 'eshell-no-numeric-conversions)
1328 (while args
1329 (let ((arg (car args)))
1330 (if (and (stringp arg)
1331 (> (length arg) 0)
1332 (not (text-property-not-all
1333 0 (length arg) 'number t arg)))
1334 (setcar args (string-to-number arg))))
1335 (setq args (cdr args))))
1336 (eshell-apply object eshell-last-arguments))
1337 (setq eshell-last-arguments args
1338 eshell-last-command-name "#<Lisp object>")
1339 (eshell-eval object))))
1340 (if (and eshell-ensure-newline-p
1341 (save-excursion
1342 (goto-char eshell-last-output-end)
1343 (not (bolp))))
1344 (eshell-print "\n"))
1345 (eshell-close-handles 0 (list 'quote result)))))
1347 (defalias 'eshell-lisp-command* 'eshell-lisp-command)
1349 (provide 'esh-cmd)
1351 ;;; esh-cmd.el ends here