Misc custom group fixes
[bpt/emacs.git] / lisp / eshell / esh-cmd.el
CommitLineData
60370d40 1;;; esh-cmd.el --- command invocation
25fffb31 2
ab422c4d 3;; Copyright (C) 1999-2013 Free Software Foundation, Inc.
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5;; Author: John Wiegley <johnw@gnu.org>
6
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7;; This file is part of GNU Emacs.
8
4ee57b2a 9;; GNU Emacs is free software: you can redistribute it and/or modify
25fffb31 10;; it under the terms of the GNU General Public License as published by
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11;; the Free Software Foundation, either version 3 of the License, or
12;; (at your option) any later version.
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13
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.
18
19;; You should have received a copy of the GNU General Public License
4ee57b2a 20;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
25fffb31 21
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22;;; Commentary:
23
24;;;_* Invoking external commands
25;;
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].
29;;
30;;;_* Invoking Lisp functions
31;;
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:
34;;
35;; /tmp $ (dired ".")
36;;
37;; Or:
38;;
39;; /tmp $ dired .
40;;
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.
45;;
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.
51
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52;;;_* Alias functions
53;;
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).
59;;
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.
64;;
65;;;_* Lisp arguments
66;;
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:
70;;
71;; echo (+ 1 2)
72;;
73;; Or
74;;
75;; echo $(+ 1 2)
76;;
77;; The two forms are equivalent. The second is required only if the
78;; form being interpolated is within a string, or is a subexpression
79;; of a larger argument:
80;;
81;; echo x$(+ 1 2) "String $(+ 1 2)"
82;;
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:
86;;
87;; echo #'lisp-symbol
88;;
89;; Backquote can also be used:
90;;
91;; echo `(list ,lisp-symbol)
92;;
93;; Lisp arguments are identified using the following regexp:
94
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95;;;_* Command hooks
96;;
97;; There are several hooks involved with command execution, which can
98;; be used either to change or augment Eshell's behavior.
99
100
101;;; Code:
102
103(require 'esh-util)
104(unless (featurep 'xemacs)
105 (require 'eldoc))
106(require 'esh-arg)
107(require 'esh-proc)
108(require 'esh-ext)
109
110(eval-when-compile
a464a6c7 111 (require 'cl-lib)
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112 (require 'pcomplete))
113
114
115(defgroup eshell-cmd nil
116 "Executing an Eshell command is as simple as typing it in and
117pressing <RET>. There are several different kinds of commands,
118however."
119 :tag "Command invocation"
120 ;; :link '(info-link "(eshell)Command invocation")
121 :group 'eshell)
122
123(defcustom eshell-prefer-lisp-functions nil
ec60da52 124 "If non-nil, prefer Lisp functions to external commands."
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125 :type 'boolean
126 :group 'eshell-cmd)
127
25fffb31 128(defcustom eshell-lisp-regexp "\\([(`]\\|#'\\)"
ec60da52 129 "A regexp which, if matched at beginning of an argument, means Lisp.
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130Such arguments will be passed to `read', and then evaluated."
131 :type 'regexp
132 :group 'eshell-cmd)
133
25fffb31 134(defcustom eshell-pre-command-hook nil
ec60da52 135 "A hook run before each interactive command is invoked."
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136 :type 'hook
137 :group 'eshell-cmd)
138
139(defcustom eshell-post-command-hook nil
ec60da52 140 "A hook run after each interactive command is invoked."
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141 :type 'hook
142 :group 'eshell-cmd)
143
144(defcustom eshell-prepare-command-hook nil
ec60da52 145 "A set of functions called to prepare a named command.
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146The command name and its argument are in `eshell-last-command-name'
147and `eshell-last-arguments'. The functions on this hook can change
148the value of these symbols if necessary.
149
150To prevent a command from executing at all, set
151`eshell-last-command-name' to nil."
152 :type 'hook
153 :group 'eshell-cmd)
154
155(defcustom eshell-named-command-hook nil
ec60da52 156 "A set of functions called before a named command is invoked.
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157Each function will be passed the command name and arguments that were
158passed to `eshell-named-command'.
159
160If any of the functions returns a non-nil value, the named command
161will not be invoked, and that value will be returned from
162`eshell-named-command'.
163
164In order to substitute an alternate command form for execution, the
165hook function should throw it using the tag `eshell-replace-command'.
166For example:
167
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)))
172
173Although useless, the above code will cause any non-glob, non-Lisp
174command (i.e., 'ls' as opposed to '*ls' or '(ls)') to be replaced by a
175call to `cd' using the arguments that were passed to the function."
176 :type 'hook
177 :group 'eshell-cmd)
178
179(defcustom eshell-pre-rewrite-command-hook
180 '(eshell-no-command-conversion
181 eshell-subcommand-arg-values)
ec60da52 182 "A hook run before command rewriting begins.
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183The terms of the command to be rewritten is passed as arguments, and
184may be modified in place. Any return value is ignored."
185 :type 'hook
186 :group 'eshell-cmd)
187
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)
ec60da52 195 "A set of functions used to rewrite the command argument.
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196Once parsing of a command line is completed, the next step is to
197rewrite the initial argument into something runnable.
198
199A module may wish to associate special behavior with certain argument
200syntaxes at the beginning of a command line. They are welcome to do
201so by adding a function to this hook. The first function to return a
202substitute command form is the one used. Each function is passed the
203command's full argument list, which is a list of sexps (typically
204forms or strings)."
205 :type 'hook
206 :group 'eshell-cmd)
207
208(defcustom eshell-post-rewrite-command-hook nil
ec60da52 209 "A hook run after command rewriting is finished.
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210Each function is passed the symbol containing the rewritten command,
211which may be modified directly. Any return value is ignored."
212 :type 'hook
213 :group 'eshell-cmd)
214
820b9143 215(defcustom eshell-complex-commands '("ls")
ec60da52 216 "A list of commands names or functions, that determine complexity.
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217That is, if a command is defined by a function named eshell/NAME,
218and NAME is part of this list, it is invoked as a complex command.
219Complex commands are always correct, but run much slower. If a
220command works fine without being part of this list, then it doesn't
221need to be.
222
223If an entry is a function, it will be called with the name, and should
224return 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)
229
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230;;; User Variables:
231
d783d303 232(defcustom eshell-cmd-load-hook nil
ec60da52 233 "A hook that gets run when `eshell-cmd' is loaded."
d783d303 234 :version "24.1" ; removed eshell-cmd-initialize
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235 :type 'hook
236 :group 'eshell-cmd)
237
238(defcustom eshell-debug-command nil
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239 "If non-nil, enable Eshell debugging code.
240This is slow, and only useful for debugging problems with Eshell.
241If you change this without using customize after Eshell has loaded,
aac7ba08 242you must re-load 'esh-cmd.el'."
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243 :initialize 'custom-initialize-default
244 :set (lambda (symbol value)
b499d8d0 245 (set symbol value)
beb83b5a 246 (load-library "esh-cmd"))
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247 :type 'boolean
248 :group 'eshell-cmd)
249
250(defcustom eshell-deferrable-commands
251 '(eshell-named-command
252 eshell-lisp-command
253 eshell-process-identity)
91af3942 254 "A list of functions which might return an asynchronous process.
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255If they return a process object, execution of the calling Eshell
256command will wait for completion (in the background) before finishing
257the command."
258 :type '(repeat function)
259 :group 'eshell-cmd)
260
261(defcustom eshell-subcommand-bindings
262 '((eshell-in-subcommand-p t)
263 (default-directory default-directory)
264 (process-environment (eshell-copy-environment)))
ec60da52 265 "A list of `let' bindings for subcommand environments."
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266 :type 'sexp
267 :group 'eshell-cmd)
268
269(put 'risky-local-variable 'eshell-subcommand-bindings t)
270
271(defvar eshell-ensure-newline-p nil
272 "If non-nil, ensure that a newline is emitted after a Lisp form.
273This can be changed by Lisp forms that are evaluated from the Eshell
274command line.")
275
276;;; Internal Variables:
277
278(defvar eshell-current-command nil)
279(defvar eshell-command-name nil)
280(defvar eshell-command-arguments nil)
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281(defvar eshell-in-pipeline-p nil
282 "Internal Eshell variable, non-nil inside a pipeline.
283Has the value 'first, 'last for the first/last commands in the pipeline,
284otherwise t.")
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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.")
290
291;;; Functions:
292
293(defsubst eshell-interactive-process ()
294 "Return currently running command process, if non-Lisp."
295 eshell-last-async-proc)
296
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)
305
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306 (add-hook 'eshell-kill-hook 'eshell-resume-command nil t)
307
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]
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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)
317
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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)
322
323 (when (eshell-using-module 'eshell-cmpl)
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324 (add-hook 'pcomplete-try-first-hook
325 'eshell-complete-lisp-symbols nil t)))
326
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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)))))
335
336;; Command parsing
337
338(defun eshell-parse-command (command &optional args top-level)
339 "Parse the COMMAND, adding ARGS if given.
340COMMAND can either be a string, or a cons cell demarcating a buffer
341region. TOP-LEVEL, if non-nil, means that the outermost command (the
342user's input command) is being parsed, and that pre and post command
343hooks 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))
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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))))))
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358 args))
359 (commands
360 (mapcar
361 (function
362 (lambda (cmd)
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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)))))
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369 (setq sep-terms (cdr sep-terms))
370 (if eshell-in-pipeline-p
371 cmd
1bc4c3ae 372 `(eshell-trap-errors ,cmd))))
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373 (eshell-separate-commands terms "[&;]" nil 'sep-terms))))
374 (let ((cmd commands))
375 (while cmd
376 (if (cdr cmd)
1bc4c3ae 377 (setcar cmd `(eshell-commands ,(car cmd))))
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378 (setq cmd (cdr cmd))))
379 (setq commands
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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)))))
25fffb31 387 (if top-level
1bc4c3ae 388 `(eshell-commands ,commands)
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389 commands)))
390
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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)))
ee5b7365 395 (with-current-buffer buf
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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)) ""))))))
401
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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))))
407
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))))))
414
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))
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421 (setcar terms `(eshell-convert
422 (eshell-command-to-value ,(car terms)))))
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423 (setq terms (cdr terms))))
424
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))))
431
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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)))
437
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438(defun eshell-rewrite-named-command (terms)
439 "If no other rewriting rule transforms TERMS, assume a named command."
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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
1bc4c3ae 446 (list sym cmd `(list ,@(cdr terms)))
f4dd1361 447 (list sym cmd))))
25fffb31 448
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449(defvar eshell-command-body)
450(defvar eshell-test-body)
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451
452(defsubst eshell-invokify-arg (arg &optional share-output silent)
453 "Change ARG so it can be invoked from a structured command.
454
455SHARE-OUTPUT, if non-nil, means this invocation should share the
456current output stream, which is separately redirectable. SILENT
457means the user and/or any redirections shouldn't see any output
458from this command. If both SHARE-OUTPUT and SILENT are non-nil,
459the 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))
1bc4c3ae 472 `(eshell-commands ,(cadr (cadr arg)) ,silent))
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473 arg))
474
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475(defvar eshell-last-command-status) ;Define in esh-io.el.
476
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477(defun eshell-rewrite-for-command (terms)
478 "Rewrite a `for' command into its equivalent Eshell command form.
479Because the implementation of `for' relies upon conditional evaluation
31096fe8 480of its argument (i.e., use of a Lisp special form), it must be
25fffb31 481implemented via rewriting, rather than as a function."
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482 (if (and (equal (car terms) "for")
483 (equal (nth 2 terms) "in"))
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484 (let ((body (car (last terms))))
485 (setcdr (last terms 2) nil)
1bc4c3ae 486 `(let ((for-items
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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))
1bc4c3ae 496 (eshell-test-body '(nil)))
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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)))
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503 (eshell-close-handles
504 eshell-last-command-status
505 (list 'quote eshell-last-command-result))))))
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506
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.
510The first of NAMES should be the positive form, and the second the
511negative. It's not likely that users should ever need to call this
512function.
513
514If VOCAL-TEST is non-nil, it means output from the test should be
515shown, 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
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521 `(progn ,test
522 (eshell-exit-success-p))))
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523
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))))
1bc4c3ae 532 (setq test `(not ,test)))
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533
534 ;; finally, create the form that represents this structured
535 ;; command
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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))))
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542
543(defun eshell-rewrite-while-command (terms)
544 "Rewrite a `while' command into its equivalent Eshell command form.
545Because the implementation of `while' relies upon conditional
546evaluation of its argument (i.e., use of a Lisp special form), it
547must 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)
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553 `(eshell-protect
554 ,(eshell-invokify-arg (car (last terms)) t)))))
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555
556(defun eshell-rewrite-if-command (terms)
557 "Rewrite an `if' command into its equivalent Eshell command form.
558Because the implementation of `if' relies upon conditional
559evaluation of its argument (i.e., use of a Lisp special form), it
560must 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)
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566 `(eshell-protect
567 ,(eshell-invokify-arg (car (last terms (if (= (length terms) 4) 2)))
568 t))
05a68572 569 (if (= (length terms) 4)
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570 `(eshell-protect
571 ,(eshell-invokify-arg (car (last terms)))) t))))
572
573(defvar eshell-last-command-result) ;Defined in esh-io.el.
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574
575(defun eshell-exit-success-p ()
576 "Return non-nil if the last command was \"successful\".
577For a bit of Lisp code, this means a return value of non-nil.
578For an external command, it means an exit code of 0."
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579 (if (save-match-data
580 (string-match "#<\\(Lisp object\\|function .*\\)>"
581 eshell-last-command-name))
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582 eshell-last-command-result
583 (= eshell-last-command-status 0)))
584
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)
a464a6c7 609 (cl-assert (not eshell-in-pipeline-p))
1bc4c3ae 610 `(eshell-execute-pipeline (quote ,pieces))))))
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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
a464a6c7 620 (cl-assert (car sep-terms))
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621 (setq final (eshell-structure-basic-command
622 'if (string= (car sep-terms) "&&") "if"
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623 `(eshell-protect ,(car results))
624 `(eshell-protect ,final)
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625 nil t)
626 results (cdr results)
627 sep-terms (cdr sep-terms)))
628 final))
629
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
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642 `(eshell-as-subcommand
643 ,(eshell-parse-command (cons (1+ (point)) end)))
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644 (goto-char (1+ end))))))))
645
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)
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658 `(eshell-command-to-value
659 (eshell-lisp-command (quote ,obj)))
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660 (ignore (goto-char here))))))
661
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662(defun eshell-separate-commands (terms separator &optional
663 reversed last-terms-sym)
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664 "Separate TERMS using SEPARATOR.
665If REVERSED is non-nil, the list of separated term groups will be
d4469517 666returned in reverse order. If LAST-TERMS-SYM is a symbol, its value
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667will be set to a list of all the separator operators found (or '(list
668nil)' 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))))
693
694;;_* Command evaluation macros
695;;
696;; The structure of the following macros is very important to
697;; `eshell-do-eval' [Iterative evaluation]:
698;;
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'.
703;;
704;; @ The main body of a `let' can contain only one form. Use `progn'
705;; if necessary.
706;;
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.
711
712(defmacro eshell-do-subjob (object)
713 "Evaluate a command OBJECT as a subjob.
6b6f91b3 714We indicate that the process was run in the background by returning it
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715ensconced in a list."
716 `(let ((eshell-current-subjob-p t))
717 ,object))
718
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))
725
726(defmacro eshell-trap-errors (object)
727 "Trap any errors that occur, so they are not entirely fatal.
728Also, the variable `eshell-this-command-hook' is available for the
729duration of OBJECT's evaluation. Note that functions should be added
730to this hook using `nconc', and *not* `add-hook'.
731
732Someday, when Scheme will become the dominant Emacs language, all of
733this grossness will be made to disappear by using `call/cc'..."
1bc4c3ae 734 `(let ((eshell-this-command-hook '(ignore)))
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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)))))
743
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744(defvar eshell-output-handle) ;Defined in esh-io.el.
745(defvar eshell-error-handle) ;Defined in esh-io.el.
746
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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))
756
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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))
762
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763(defmacro eshell-do-pipelines (pipeline &optional notfirst)
764 "Execute the commands in PIPELINE, connecting each to one another.
765This macro calls itself recursively, with NOTFIRST non-nil."
25fffb31 766 (when (setq pipeline (cadr pipeline))
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767 `(eshell-copy-handles
768 (progn
769 ,(when (cdr pipeline)
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770 `(let ((nextproc
771 (eshell-do-pipelines (quote ,(cdr pipeline)) t)))
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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))))
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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)) "*"))))))
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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)))))
3fe3fd2c 792 ,(car pipeline))))))
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793
794(defmacro eshell-do-pipelines-synchronously (pipeline)
795 "Execute the commands in PIPELINE in sequence synchronously.
796Output of each command is passed as input to the next one in the pipeline.
797This is used on systems where `start-process' is not supported."
798 (when (setq pipeline (cadr pipeline))
6dbe3e96 799 `(progn
1bc4c3ae 800 ,(when (cdr pipeline)
6dbe3e96 801 `(let ((output-marker ,(point-marker)))
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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
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813 (intern-soft
814 (concat (symbol-name (car head)) "*"))))))
815 ;; The last process in the pipe should get its handles
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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)))
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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))))
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828
829(defalias 'eshell-process-identity 'identity)
830
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
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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)))
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843 (eshell-process-identity tailproc))))
844
845(defmacro eshell-as-subcommand (command)
846 "Execute COMMAND using a temp buffer.
847This is used so that certain Lisp commands, such as `cd', when
848executed in a subshell, do not disturb the environment of the main
849Eshell buffer."
850 `(let ,eshell-subcommand-bindings
851 ,command))
852
853(defmacro eshell-do-command-to-value (object)
854 "Run a subcommand prepared by `eshell-command-to-value'.
855This 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))))
861
862(defmacro eshell-command-to-value (object)
863 "Run OBJECT synchronously, returning its result as a string.
864Returns a string comprising the output from the command."
865 `(let ((value (make-symbol "eshell-temp")))
866 (eshell-do-command-to-value ,object)))
867
868;;;_* Iterative evaluation
869;;
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.
875;;
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.
882
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")))
6dbe3e96 892 ((member (car args) '("-h" "--help"))
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893 (eshell-print "usage: eshell-debug [kinds]
894
895This command is used to aid in debugging problems related to Eshell
896itself. It is not useful for anything else. The recognized `kinds'
897at the moment are:
898
899 errors stops Eshell from trapping errors
900 commands shows command execution progress in `*eshell last cmd*'
901"))
902 (t
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)))))))
910
911(defun pcomplete/eshell-mode/eshell-debug ()
912 "Completion for the `debug' command."
913 (while (pcomplete-here '("errors" "commands"))))
914
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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
a9eeff78 924 (dolist (pred eshell-complex-commands)
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925 (if (and (functionp pred)
926 (funcall pred name))
927 (throw 'simple nil)))
928 t))
929 (fboundp (intern-soft (concat "eshell/" name))))))
930
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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))
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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))))
25fffb31 943 (and eshell-debug-command
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944 (with-current-buffer (get-buffer-create "*eshell last cmd*")
945 (erase-buffer)
946 (insert "command: \"" input "\"\n")))
25fffb31 947 (setq eshell-current-command command)
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948 (let ((delim (catch 'eshell-incomplete
949 (eshell-resume-eval))))
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950 ;; On systems that don't support async subprocesses, eshell-resume
951 ;; can return t. Don't treat that as an error.
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952 (if (listp delim)
953 (setq delim (car delim)))
4c334f5b 954 (if (and delim (not (eq delim t)))
6b6f91b3 955 (error "Unmatched delimiter: %c" delim)))))
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956
957(defun eshell-resume-command (proc status)
958 "Resume the current command when a process ends."
959 (when proc
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960 (unless (or (not (stringp status))
961 (string= "stopped" status)
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962 (string-match eshell-reset-signals status))
963 (if (eq proc (eshell-interactive-process))
964 (eshell-resume-eval)))))
965
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))))))
ca7aae91 978 (if (eshell-processp proc)
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979 (ignore (setq eshell-last-async-proc proc))
980 (cadr retval)))))
981 (error
982 (error (error-message-string err)))))
983
984(defmacro eshell-manipulate (tag &rest commands)
985 "Manipulate a COMMAND form, with TAG as a debug identifier."
1bc4c3ae 986 (declare (indent 1))
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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))
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990 `(progn ,@commands)
991 `(progn
992 (eshell-debug-command ,(eval tag) form)
993 ,@commands
994 (eshell-debug-command ,(concat "done " (eval tag)) form))))
995
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996(defsubst eshell-macrop (object)
997 "Return t if OBJECT is a macro or nil otherwise."
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998 (and (symbolp object) (fboundp object)
999 (setq object (indirect-function object))
1000 (listp object)
1001 (eq 'macro (car object))
1002 (functionp (cdr object))))
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1003
1004(defun eshell-do-eval (form &optional synchronous-p)
1005 "Evaluate form, simplifying it as we go.
1006Unless SYNCHRONOUS-P is non-nil, throws `eshell-defer' if it needs to
1007be 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)
1013 (t
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)
a464a6c7 1031 (cl-assert (not synchronous-p))
25fffb31 1032 (eshell-do-eval (car eshell-command-body))
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1033 (setcar eshell-command-body nil)
1034 (setcar eshell-test-body nil))
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1035 (unless (car eshell-test-body)
1036 (setcar eshell-test-body (eshell-copy-tree (car args))))
ca7aae91 1037 (while (cadr (eshell-do-eval (car eshell-test-body)))
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1038 (setcar eshell-command-body
1039 (if (cddr args)
1040 `(progn ,@(eshell-copy-tree (cdr args)))
1041 (eshell-copy-tree (cadr args))))
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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))))
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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.
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1049 (if (car eshell-command-body)
1050 (progn
a464a6c7 1051 (cl-assert (not synchronous-p))
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1052 (eshell-do-eval (car eshell-command-body)))
1053 (unless (car eshell-test-body)
1054 (setcar eshell-test-body (eshell-copy-tree (car args))))
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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)))))
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1060 (eshell-do-eval (car eshell-command-body) synchronous-p))
1061 (setcar eshell-command-body nil)
1062 (setcar eshell-test-body nil))
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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.
1073 ;;
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"
a9eeff78 1080 (dolist (letarg (car args))
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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"
1bc4c3ae 1090 (setcar args `(eshell-do-eval ',(car args) ,synchronous-p))))
25fffb31 1091 (eval form))
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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)))
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1097 (t
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))
1110 (t
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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:
1116 ;;
1117 ;; (eshell-named-command "hello")
1118 ;;
1119 ;; Now, let's assume the 'hello' command is an Eshell alias,
1120 ;; the definition of which yields the command:
1121 ;;
1122 ;; (eshell-named-command "echo" (list "Hello" "world"))
1123 ;;
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.
6dbe3e96
SM
1133 (let* (result
1134 (new-form
1135 (catch 'eshell-replace-command
1136 (ignore
1137 (setq result (eval form))))))
1138 (if new-form
25fffb31
GM
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
ca7aae91 1147 (eshell-processp result))
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GM
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))))))))))))
1155
1156;; command invocation
1157
1158(defun eshell/which (command &rest names)
1159 "Identify the COMMAND, and where it is located."
a9eeff78 1160 (dolist (name (cons command names))
25fffb31 1161 (let (program alias direct)
94d13633 1162 (if (eq (aref name 0) eshell-explicit-command-char)
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GM
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))))
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1177 (if (and (or esym (and sym (fboundp sym)))
1178 (or eshell-prefer-lisp-functions (not direct)))
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GM
1179 (let ((desc (let ((inhibit-redisplay t))
1180 (save-window-excursion
1181 (prog1
1182 (describe-function sym)
1183 (message nil))))))
c1043701
GM
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, \
1189but no documentation was found" name)))
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JW
1190 (if (buffer-live-p (get-buffer "*Help*"))
1191 (kill-buffer "*Help*"))
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GM
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)))))
1197
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1198(put 'eshell/which 'eshell-no-numeric-conversions t)
1199
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1200(defun eshell-named-command (command &optional args)
1201 "Insert output from a plain COMMAND, using ARGS.
1202COMMAND 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)
a464a6c7 1206 (cl-assert (stringp eshell-last-command-name))
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GM
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))))
1213
1214(defalias 'eshell-named-command* 'eshell-named-command)
1215
1216(defun eshell-find-alias-function (name)
1217 "Check whether a function called `eshell/NAME' exists."
1218 (let* ((sym (intern-soft (concat "eshell/" name)))
5cb345c1 1219 (file (symbol-file sym 'defun)))
c7b1b508 1220 ;; If the function exists, but is defined in an eshell module
9a48e168 1221 ;; that's not currently enabled, don't report it as found.
25fffb31 1222 (if (and file
9a48e168
GM
1223 (setq file (file-name-base file))
1224 (string-match "\\`\\(em\\|esh\\)-\\([[:alnum:]]+\\)\\'" file))
c7b1b508 1225 (let ((module-sym
9a48e168 1226 (intern (concat "eshell-" (match-string 2 file)))))
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JW
1227 (if (and (functionp sym)
1228 (or (null module-sym)
1229 (eshell-using-module module-sym)
1230 (memq module-sym (eshell-subgroups 'eshell))))
c7b1b508
JW
1231 sym))
1232 ;; Otherwise, if it's bound, return it.
1233 (if (functionp sym)
1234 sym))))
25fffb31
GM
1235
1236(defun eshell-plain-command (command args)
1237 "Insert output from a plain COMMAND, using ARGS.
1238COMMAND may result in either a Lisp function being executed by name,
1239or 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))))
1247
1248(defun eshell-exec-lisp (printer errprint func-or-form args form-p)
1249 "Execute a lisp FUNC-OR-FORM, maybe passing ARGS.
1250PRINTER and ERRPRINT are functions to use for printing regular
1251messages, and errors. FORM-P should be non-nil if FUNC-OR-FORM
1252represent a lisp form; ARGS will be ignored in that case."
6dbe3e96
SM
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)))
25fffb31
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1270
1271(defsubst eshell-apply* (printer errprint func args)
1272 "Call FUNC, with ARGS, trapping errors and return them as output.
1273PRINTER and ERRPRINT are functions to use for printing regular
1274messages, and errors."
1275 (eshell-exec-lisp printer errprint func args nil))
1276
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))
1280
1281(defsubst eshell-eval* (printer errprint form)
1282 "Evaluate FORM, trapping errors and returning them."
1283 (eshell-exec-lisp printer errprint form nil t))
1284
1285(defsubst eshell-apply (func args)
1286 "Call FUNC, with ARGS, trapping errors and return them as output.
1287PRINTER and ERRPRINT are functions to use for printing regular
1288messages, and errors."
1289 (eshell-apply* 'eshell-print 'eshell-error func args))
1290
1291(defsubst eshell-funcall (func &rest args)
1292 "Call FUNC, with ARGS, trapping errors and return them as output."
1293 (eshell-apply func args))
1294
1295(defsubst eshell-eval (form)
1296 "Evaluate FORM, trapping errors and returning them."
1297 (eshell-eval* 'eshell-print 'eshell-error form))
1298
1299(defsubst eshell-applyn (func args)
1300 "Call FUNC, with ARGS, trapping errors and return them as output.
1301PRINTER and ERRPRINT are functions to use for printing regular
1302messages, and errors."
1303 (eshell-apply* 'eshell-printn 'eshell-errorn func args))
1304
1305(defsubst eshell-funcalln (func &rest args)
1306 "Call FUNC, with ARGS, trapping errors and return them as output."
1307 (eshell-applyn func args))
1308
1309(defsubst eshell-evaln (form)
1310 "Evaluate FORM, trapping errors and returning them."
1311 (eshell-eval* 'eshell-printn 'eshell-errorn form))
1312
1bc4c3ae
SM
1313(defvar eshell-last-output-end) ;Defined in esh-mode.el.
1314
25fffb31
GM
1315(defun eshell-lisp-command (object &optional args)
1316 "Insert Lisp OBJECT, using ARGS if a function."
25fffb31
GM
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)
3cb27fd7
JW
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)
175acc2d
JW
1332 (not (text-property-not-all
1333 0 (length arg) 'number t arg)))
ea7974a6 1334 (setcar args (string-to-number arg))))
3cb27fd7
JW
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>")
25fffb31
GM
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)))))
1346
1347(defalias 'eshell-lisp-command* 'eshell-lisp-command)
1348
56590d2f
GM
1349(provide 'esh-cmd)
1350
25fffb31 1351;;; esh-cmd.el ends here