Fix Bug#24962
[emacs.git] / lisp / eshell / esh-cmd.el
blobd3613d31405840dd2fc788c308931832991c3bbb
1 ;;; esh-cmd.el --- command invocation -*- lexical-binding:t -*-
3 ;; Copyright (C) 1999-2016 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 (defvar eshell-post-rewrite-command-function #'identity
209 "Function run after command rewriting is finished.
210 Takes the (rewritten) command, modifies it as it sees fit and returns
211 the new result to use instead.")
212 (defvar eshell-post-rewrite-command-hook nil
213 "A hook run after command rewriting is finished.
214 Each function is passed the symbol containing the rewritten command,
215 which may be modified directly. Any return value is ignored.")
216 (make-obsolete-variable 'eshell-post-rewrite-command-hook
217 'eshell-post-rewrite-command-function "24.4")
219 (defcustom eshell-complex-commands '("ls")
220 "A list of commands names or functions, that determine complexity.
221 That is, if a command is defined by a function named eshell/NAME,
222 and NAME is part of this list, it is invoked as a complex command.
223 Complex commands are always correct, but run much slower. If a
224 command works fine without being part of this list, then it doesn't
225 need to be.
227 If an entry is a function, it will be called with the name, and should
228 return non-nil if the command is complex."
229 :type '(repeat :tag "Commands"
230 (choice (string :tag "Name")
231 (function :tag "Predicate")))
232 :group 'eshell-cmd)
234 ;;; User Variables:
236 (defcustom eshell-cmd-load-hook nil
237 "A hook that gets run when `eshell-cmd' is loaded."
238 :version "24.1" ; removed eshell-cmd-initialize
239 :type 'hook
240 :group 'eshell-cmd)
242 (defcustom eshell-debug-command nil
243 "If non-nil, enable Eshell debugging code.
244 This is slow, and only useful for debugging problems with Eshell.
245 If you change this without using customize after Eshell has loaded,
246 you must re-load `esh-cmd.el'."
247 :initialize 'custom-initialize-default
248 :set (lambda (symbol value)
249 (set symbol value)
250 (load-library "esh-cmd"))
251 :type 'boolean
252 :group 'eshell-cmd)
254 (defcustom eshell-deferrable-commands
255 '(eshell-named-command
256 eshell-lisp-command
257 eshell-process-identity)
258 "A list of functions which might return an asynchronous process.
259 If they return a process object, execution of the calling Eshell
260 command will wait for completion (in the background) before finishing
261 the command."
262 :type '(repeat function)
263 :group 'eshell-cmd)
265 (defcustom eshell-subcommand-bindings
266 '((eshell-in-subcommand-p t)
267 (default-directory default-directory)
268 (process-environment (eshell-copy-environment)))
269 "A list of `let' bindings for subcommand environments."
270 :type 'sexp
271 :group 'eshell-cmd)
273 (put 'risky-local-variable 'eshell-subcommand-bindings t)
275 (defvar eshell-ensure-newline-p nil
276 "If non-nil, ensure that a newline is emitted after a Lisp form.
277 This can be changed by Lisp forms that are evaluated from the Eshell
278 command line.")
280 ;;; Internal Variables:
282 (defvar eshell-current-command nil)
283 (defvar eshell-command-name nil)
284 (defvar eshell-command-arguments nil)
285 (defvar eshell-in-pipeline-p nil
286 "Internal Eshell variable, non-nil inside a pipeline.
287 Has the value `first', `last' for the first/last commands in the pipeline,
288 otherwise t.")
289 (defvar eshell-in-subcommand-p nil)
290 (defvar eshell-last-arguments nil)
291 (defvar eshell-last-command-name nil)
292 (defvar eshell-last-async-proc nil
293 "When this foreground process completes, resume command evaluation.")
295 ;;; Functions:
297 (defsubst eshell-interactive-process ()
298 "Return currently running command process, if non-Lisp."
299 eshell-last-async-proc)
301 (defun eshell-cmd-initialize ()
302 "Initialize the Eshell command processing module."
303 (set (make-local-variable 'eshell-current-command) nil)
304 (set (make-local-variable 'eshell-command-name) nil)
305 (set (make-local-variable 'eshell-command-arguments) nil)
306 (set (make-local-variable 'eshell-last-arguments) nil)
307 (set (make-local-variable 'eshell-last-command-name) nil)
308 (set (make-local-variable 'eshell-last-async-proc) nil)
310 (add-hook 'eshell-kill-hook 'eshell-resume-command nil t)
312 ;; make sure that if a command is over, and no process is being
313 ;; waited for, that `eshell-current-command' is set to nil. This
314 ;; situation can occur, for example, if a Lisp function results in
315 ;; `debug' being called, and the user then types \\[top-level]
316 (add-hook 'eshell-post-command-hook
317 (function
318 (lambda ()
319 (setq eshell-current-command nil
320 eshell-last-async-proc nil))) nil t)
322 (add-hook 'eshell-parse-argument-hook
323 'eshell-parse-subcommand-argument nil t)
324 (add-hook 'eshell-parse-argument-hook
325 'eshell-parse-lisp-argument nil t)
327 (when (eshell-using-module 'eshell-cmpl)
328 (add-hook 'pcomplete-try-first-hook
329 'eshell-complete-lisp-symbols nil t)))
331 (defun eshell-complete-lisp-symbols ()
332 "If there is a user reference, complete it."
333 (let ((arg (pcomplete-actual-arg)))
334 (when (string-match (concat "\\`" eshell-lisp-regexp) arg)
335 (setq pcomplete-stub (substring arg (match-end 0))
336 pcomplete-last-completion-raw t)
337 (throw 'pcomplete-completions
338 (all-completions pcomplete-stub obarray 'boundp)))))
340 ;; Command parsing
342 (defvar eshell--sep-terms)
344 (defun eshell-parse-command (command &optional args toplevel)
345 "Parse the COMMAND, adding ARGS if given.
346 COMMAND can either be a string, or a cons cell demarcating a buffer
347 region. TOPLEVEL, if non-nil, means that the outermost command (the
348 user's input command) is being parsed, and that pre and post command
349 hooks should be run before and after the command."
350 (let* (eshell--sep-terms
351 (terms
352 (append
353 (if (consp command)
354 (eshell-parse-arguments (car command) (cdr command))
355 (let ((here (point))
356 (inhibit-point-motion-hooks t))
357 (with-silent-modifications
358 ;; FIXME: Why not use a temporary buffer and avoid this
359 ;; "insert&delete" business? --Stef
360 (insert command)
361 (prog1
362 (eshell-parse-arguments here (point))
363 (delete-region here (point))))))
364 args))
365 (commands
366 (mapcar
367 (function
368 (lambda (cmd)
369 (setq cmd
370 (if (or (not (car eshell--sep-terms))
371 (string= (car eshell--sep-terms) ";"))
372 (eshell-parse-pipeline cmd)
373 `(eshell-do-subjob
374 (list ,(eshell-parse-pipeline cmd)))))
375 (setq eshell--sep-terms (cdr eshell--sep-terms))
376 (if eshell-in-pipeline-p
378 `(eshell-trap-errors ,cmd))))
379 (eshell-separate-commands terms "[&;]" nil 'eshell--sep-terms))))
380 (let ((cmd commands))
381 (while cmd
382 (if (cdr cmd)
383 (setcar cmd `(eshell-commands ,(car cmd))))
384 (setq cmd (cdr cmd))))
385 (if toplevel
386 `(eshell-commands (progn
387 (run-hooks 'eshell-pre-command-hook)
388 (catch 'top-level (progn ,@commands))
389 (run-hooks 'eshell-post-command-hook)))
390 (macroexp-progn commands))))
392 (defun eshell-debug-command (tag subform)
393 "Output a debugging message to `*eshell last cmd*'."
394 (let ((buf (get-buffer-create "*eshell last cmd*"))
395 (text (eshell-stringify eshell-current-command)))
396 (with-current-buffer buf
397 (if (not tag)
398 (erase-buffer)
399 (insert "\n\C-l\n" tag "\n\n" text
400 (if subform
401 (concat "\n\n" (eshell-stringify subform)) ""))))))
403 (defun eshell-debug-show-parsed-args (terms)
404 "Display parsed arguments in the debug buffer."
405 (ignore
406 (if eshell-debug-command
407 (eshell-debug-command "parsed arguments" terms))))
409 (defun eshell-no-command-conversion (terms)
410 "Don't convert the command argument."
411 (ignore
412 (if (and (listp (car terms))
413 (eq (caar terms) 'eshell-convert))
414 (setcar terms (cadr (car terms))))))
416 (defun eshell-subcommand-arg-values (terms)
417 "Convert subcommand arguments {x} to ${x}, in order to take their values."
418 (setq terms (cdr terms)) ; skip command argument
419 (while terms
420 (if (and (listp (car terms))
421 (eq (caar terms) 'eshell-as-subcommand))
422 (setcar terms `(eshell-convert
423 (eshell-command-to-value ,(car terms)))))
424 (setq terms (cdr terms))))
426 (defun eshell-rewrite-sexp-command (terms)
427 "Rewrite a sexp in initial position, such as `(+ 1 2)'."
428 ;; this occurs when a Lisp expression is in first position
429 (if (and (listp (car terms))
430 (eq (caar terms) 'eshell-command-to-value))
431 (car (cdar terms))))
433 (defun eshell-rewrite-initial-subcommand (terms)
434 "Rewrite a subcommand in initial position, such as `{+ 1 2}'."
435 (if (and (listp (car terms))
436 (eq (caar terms) 'eshell-as-subcommand))
437 (car terms)))
439 (defun eshell-rewrite-named-command (terms)
440 "If no other rewriting rule transforms TERMS, assume a named command."
441 (let ((sym (if eshell-in-pipeline-p
442 'eshell-named-command*
443 'eshell-named-command))
444 (cmd (car terms))
445 (args (cdr terms)))
446 (if args
447 (list sym cmd `(list ,@(cdr terms)))
448 (list sym cmd))))
450 (defvar eshell-command-body)
451 (defvar eshell-test-body)
453 (defsubst eshell-invokify-arg (arg &optional share-output silent)
454 "Change ARG so it can be invoked from a structured command.
456 SHARE-OUTPUT, if non-nil, means this invocation should share the
457 current output stream, which is separately redirectable. SILENT
458 means the user and/or any redirections shouldn't see any output
459 from this command. If both SHARE-OUTPUT and SILENT are non-nil,
460 the second is ignored."
461 ;; something that begins with `eshell-convert' means that it
462 ;; intends to return a Lisp value. We want to get past this,
463 ;; but if it's not _actually_ a value interpolation -- in which
464 ;; we leave it alone. In fact, the only time we muck with it
465 ;; is in the case of a {subcommand} that has been turned into
466 ;; the interpolation, ${subcommand}, by the parser because it
467 ;; didn't know better.
468 (if (and (listp arg)
469 (eq (car arg) 'eshell-convert)
470 (eq (car (cadr arg)) 'eshell-command-to-value))
471 (if share-output
472 (cadr (cadr arg))
473 `(eshell-commands ,(cadr (cadr arg)) ,silent))
474 arg))
476 (defvar eshell-last-command-status) ;Define in esh-io.el.
477 (defvar eshell--local-vars nil
478 "List of locally bound vars that should take precedence over env-vars.")
480 (defun eshell-rewrite-for-command (terms)
481 "Rewrite a `for' command into its equivalent Eshell command form.
482 Because the implementation of `for' relies upon conditional evaluation
483 of its argument (i.e., use of a Lisp special form), it must be
484 implemented via rewriting, rather than as a function."
485 (if (and (equal (car terms) "for")
486 (equal (nth 2 terms) "in"))
487 (let ((body (car (last terms))))
488 (setcdr (last terms 2) nil)
489 `(let ((for-items
490 (copy-tree
491 (append
492 ,@(mapcar
493 (lambda (elem)
494 (if (listp elem)
495 elem
496 `(list ,elem)))
497 (cdr (cddr terms))))))
498 (eshell-command-body '(nil))
499 (eshell-test-body '(nil)))
500 (while (car for-items)
501 (let ((,(intern (cadr terms)) (car for-items))
502 (eshell--local-vars (cons ',(intern (cadr terms))
503 eshell--local-vars)))
504 (eshell-protect
505 ,(eshell-invokify-arg body t)))
506 (setcar for-items (cadr for-items))
507 (setcdr for-items (cddr for-items)))
508 (eshell-close-handles
509 eshell-last-command-status
510 (list 'quote eshell-last-command-result))))))
512 (defun eshell-structure-basic-command (func names keyword test body
513 &optional else)
514 "With TERMS, KEYWORD, and two NAMES, structure a basic command.
515 The first of NAMES should be the positive form, and the second the
516 negative. It's not likely that users should ever need to call this
517 function."
518 ;; If the test form begins with `eshell-convert', it means
519 ;; something data-wise will be returned, and we should let
520 ;; that determine the truth of the statement.
521 (unless (eq (car test) 'eshell-convert)
522 (setq test
523 `(progn ,test
524 (eshell-exit-success-p))))
526 ;; should we reverse the sense of the test? This depends
527 ;; on the `names' parameter. If it's the symbol nil, yes.
528 ;; Otherwise, it can be a pair of strings; if the keyword
529 ;; we're using matches the second member of that pair (a
530 ;; list), we should reverse it.
531 (if (or (eq names nil)
532 (and (listp names)
533 (string= keyword (cadr names))))
534 (setq test `(not ,test)))
536 ;; finally, create the form that represents this structured
537 ;; command
538 `(let ((eshell-command-body '(nil))
539 (eshell-test-body '(nil)))
540 (,func ,test ,body ,else)
541 (eshell-close-handles
542 eshell-last-command-status
543 (list 'quote eshell-last-command-result))))
545 (defun eshell-rewrite-while-command (terms)
546 "Rewrite a `while' command into its equivalent Eshell command form.
547 Because the implementation of `while' relies upon conditional
548 evaluation of its argument (i.e., use of a Lisp special form), it
549 must be implemented via rewriting, rather than as a function."
550 (if (and (stringp (car terms))
551 (member (car terms) '("while" "until")))
552 (eshell-structure-basic-command
553 'while '("while" "until") (car terms)
554 (eshell-invokify-arg (cadr terms) nil t)
555 `(eshell-protect
556 ,(eshell-invokify-arg (car (last terms)) t)))))
558 (defun eshell-rewrite-if-command (terms)
559 "Rewrite an `if' command into its equivalent Eshell command form.
560 Because the implementation of `if' relies upon conditional
561 evaluation of its argument (i.e., use of a Lisp special form), it
562 must be implemented via rewriting, rather than as a function."
563 (if (and (stringp (car terms))
564 (member (car terms) '("if" "unless")))
565 (eshell-structure-basic-command
566 'if '("if" "unless") (car terms)
567 (eshell-invokify-arg (cadr terms) nil t)
568 `(eshell-protect
569 ,(eshell-invokify-arg (car (last terms (if (= (length terms) 4) 2)))
571 (if (= (length terms) 4)
572 `(eshell-protect
573 ,(eshell-invokify-arg (car (last terms)))) t))))
575 (defvar eshell-last-command-result) ;Defined in esh-io.el.
577 (defun eshell-exit-success-p ()
578 "Return non-nil if the last command was \"successful\".
579 For a bit of Lisp code, this means a return value of non-nil.
580 For an external command, it means an exit code of 0."
581 (if (save-match-data
582 (string-match "#<\\(Lisp object\\|function .*\\)>"
583 eshell-last-command-name))
584 eshell-last-command-result
585 (= eshell-last-command-status 0)))
587 (defvar eshell--cmd)
589 (defun eshell-parse-pipeline (terms)
590 "Parse a pipeline from TERMS, return the appropriate Lisp forms."
591 (let* (eshell--sep-terms
592 (bigpieces (eshell-separate-commands terms "\\(&&\\|||\\)"
593 nil 'eshell--sep-terms))
594 (bp bigpieces)
595 (results (list t))
596 final)
597 (while bp
598 (let ((subterms (car bp)))
599 (let* ((pieces (eshell-separate-commands subterms "|"))
600 (p pieces))
601 (while p
602 (let ((cmd (car p)))
603 (run-hook-with-args 'eshell-pre-rewrite-command-hook cmd)
604 (setq cmd (run-hook-with-args-until-success
605 'eshell-rewrite-command-hook cmd))
606 (let ((eshell--cmd cmd))
607 (run-hook-with-args 'eshell-post-rewrite-command-hook
608 'eshell--cmd)
609 (setq cmd eshell--cmd))
610 (setcar p (funcall eshell-post-rewrite-command-function cmd)))
611 (setq p (cdr p)))
612 (nconc results
613 (list
614 (if (<= (length pieces) 1)
615 (car pieces)
616 (cl-assert (not eshell-in-pipeline-p))
617 `(eshell-execute-pipeline (quote ,pieces))))))
618 (setq bp (cdr bp))))
619 ;; `results' might be empty; this happens in the case of
620 ;; multi-line input
621 (setq results (cdr results)
622 results (nreverse results)
623 final (car results)
624 results (cdr results)
625 eshell--sep-terms (nreverse eshell--sep-terms))
626 (while results
627 (cl-assert (car eshell--sep-terms))
628 (setq final (eshell-structure-basic-command
629 'if (string= (car eshell--sep-terms) "&&") "if"
630 `(eshell-protect ,(car results))
631 `(eshell-protect ,final))
632 results (cdr results)
633 eshell--sep-terms (cdr eshell--sep-terms)))
634 final))
636 (defun eshell-parse-subcommand-argument ()
637 "Parse a subcommand argument of the form `{command}'."
638 (if (and (not eshell-current-argument)
639 (not eshell-current-quoted)
640 (eq (char-after) ?\{)
641 (or (= (point-max) (1+ (point)))
642 (not (eq (char-after (1+ (point))) ?\}))))
643 (let ((end (eshell-find-delimiter ?\{ ?\})))
644 (if (not end)
645 (throw 'eshell-incomplete ?\{)
646 (when (eshell-arg-delimiter (1+ end))
647 (prog1
648 `(eshell-as-subcommand
649 ,(eshell-parse-command (cons (1+ (point)) end)))
650 (goto-char (1+ end))))))))
652 (defun eshell-parse-lisp-argument ()
653 "Parse a Lisp expression which is specified as an argument."
654 (if (and (not eshell-current-argument)
655 (not eshell-current-quoted)
656 (looking-at eshell-lisp-regexp))
657 (let* ((here (point))
658 (obj
659 (condition-case nil
660 (read (current-buffer))
661 (end-of-file
662 (throw 'eshell-incomplete ?\()))))
663 (if (eshell-arg-delimiter)
664 `(eshell-command-to-value
665 (eshell-lisp-command (quote ,obj)))
666 (ignore (goto-char here))))))
668 (defun eshell-separate-commands (terms separator &optional
669 reversed last-terms-sym)
670 "Separate TERMS using SEPARATOR.
671 If REVERSED is non-nil, the list of separated term groups will be
672 returned in reverse order. If LAST-TERMS-SYM is a symbol, its value
673 will be set to a list of all the separator operators found (or (nil)
674 if none)."
675 (let ((sub-terms (list t))
676 (eshell-sep-terms (list t))
677 subchains)
678 (while terms
679 (if (and (consp (car terms))
680 (eq (caar terms) 'eshell-operator)
681 (string-match (concat "^" separator "$")
682 (nth 1 (car terms))))
683 (progn
684 (nconc eshell-sep-terms (list (nth 1 (car terms))))
685 (setq subchains (cons (cdr sub-terms) subchains)
686 sub-terms (list t)))
687 (nconc sub-terms (list (car terms))))
688 (setq terms (cdr terms)))
689 (if (> (length sub-terms) 1)
690 (setq subchains (cons (cdr sub-terms) subchains)))
691 (if reversed
692 (progn
693 (if last-terms-sym
694 (set last-terms-sym (reverse (cdr eshell-sep-terms))))
695 subchains) ; already reversed
696 (if last-terms-sym
697 (set last-terms-sym (cdr eshell-sep-terms)))
698 (nreverse subchains))))
700 ;;_* Command evaluation macros
702 ;; The structure of the following macros is very important to
703 ;; `eshell-do-eval' [Iterative evaluation]:
705 ;; @ Don't use forms that conditionally evaluate their arguments, such
706 ;; as `setq', `if', `while', `let*', etc. The only special forms
707 ;; that can be used are `let', `condition-case' and
708 ;; `unwind-protect'.
710 ;; @ The main body of a `let' can contain only one form. Use `progn'
711 ;; if necessary.
713 ;; @ The two `special' variables are `eshell-current-handles' and
714 ;; `eshell-current-subjob-p'. Bind them locally with a `let' if you
715 ;; need to change them. Change them directly only if your intention
716 ;; is to change the calling environment.
718 (defmacro eshell-do-subjob (object)
719 "Evaluate a command OBJECT as a subjob.
720 We indicate that the process was run in the background by returning it
721 ensconced in a list."
722 `(let ((eshell-current-subjob-p t))
723 ,object))
725 (defmacro eshell-commands (object &optional silent)
726 "Place a valid set of handles, and context, around command OBJECT."
727 `(let ((eshell-current-handles
728 (eshell-create-handles ,(not silent) 'append))
729 eshell-current-subjob-p)
730 ,object))
732 (defmacro eshell-trap-errors (object)
733 "Trap any errors that occur, so they are not entirely fatal.
734 Also, the variable `eshell-this-command-hook' is available for the
735 duration of OBJECT's evaluation. Note that functions should be added
736 to this hook using `nconc', and *not* `add-hook'.
738 Someday, when Scheme will become the dominant Emacs language, all of
739 this grossness will be made to disappear by using `call/cc'..."
740 `(let ((eshell-this-command-hook '(ignore)))
741 (eshell-condition-case err
742 (prog1
743 ,object
744 (run-hooks 'eshell-this-command-hook))
745 (error
746 (run-hooks 'eshell-this-command-hook)
747 (eshell-errorn (error-message-string err))
748 (eshell-close-handles 1)))))
750 (defvar eshell-output-handle) ;Defined in esh-io.el.
751 (defvar eshell-error-handle) ;Defined in esh-io.el.
753 (defmacro eshell-copy-handles (object)
754 "Duplicate current I/O handles, so OBJECT works with its own copy."
755 `(let ((eshell-current-handles
756 (eshell-create-handles
757 (car (aref eshell-current-handles
758 eshell-output-handle)) nil
759 (car (aref eshell-current-handles
760 eshell-error-handle)) nil)))
761 ,object))
763 (defmacro eshell-protect (object)
764 "Protect I/O handles, so they aren't get closed after eval'ing OBJECT."
765 `(progn
766 (eshell-protect-handles eshell-current-handles)
767 ,object))
769 (defmacro eshell-do-pipelines (pipeline &optional notfirst)
770 "Execute the commands in PIPELINE, connecting each to one another.
771 This macro calls itself recursively, with NOTFIRST non-nil."
772 (when (setq pipeline (cadr pipeline))
773 `(eshell-copy-handles
774 (progn
775 ,(when (cdr pipeline)
776 `(let ((nextproc
777 (eshell-do-pipelines (quote ,(cdr pipeline)) t)))
778 (eshell-set-output-handle ,eshell-output-handle
779 'append nextproc)
780 (eshell-set-output-handle ,eshell-error-handle
781 'append nextproc)
782 (setq tailproc (or tailproc nextproc))))
783 ,(let ((head (car pipeline)))
784 (if (memq (car head) '(let progn))
785 (setq head (car (last head))))
786 (when (memq (car head) eshell-deferrable-commands)
787 (ignore
788 (setcar head
789 (intern-soft
790 (concat (symbol-name (car head)) "*"))))))
791 ;; First and last elements in a pipeline may need special treatment.
792 ;; (Currently only eshell-ls-files uses 'last.)
793 ;; Affects process-connection-type in eshell-gather-process-output.
794 (let ((eshell-in-pipeline-p
795 ,(cond ((not notfirst) (quote 'first))
796 ((cdr pipeline) t)
797 (t (quote 'last)))))
798 ,(car pipeline))))))
800 (defmacro eshell-do-pipelines-synchronously (pipeline)
801 "Execute the commands in PIPELINE in sequence synchronously.
802 Output of each command is passed as input to the next one in the pipeline.
803 This is used on systems where async subprocesses are not supported."
804 (when (setq pipeline (cadr pipeline))
805 `(progn
806 ,(when (cdr pipeline)
807 `(let ((output-marker ,(point-marker)))
808 (eshell-set-output-handle ,eshell-output-handle
809 'append output-marker)
810 (eshell-set-output-handle ,eshell-error-handle
811 'append output-marker)))
812 ,(let ((head (car pipeline)))
813 (if (memq (car head) '(let progn))
814 (setq head (car (last head))))
815 ;; FIXME: is deferrable significant here?
816 (when (memq (car head) eshell-deferrable-commands)
817 (ignore
818 (setcar head
819 (intern-soft
820 (concat (symbol-name (car head)) "*"))))))
821 ;; The last process in the pipe should get its handles
822 ;; redirected as we found them before running the pipe.
823 ,(if (null (cdr pipeline))
824 `(progn
825 (setq eshell-current-handles tail-handles)
826 (setq eshell-in-pipeline-p nil)))
827 (let ((result ,(car pipeline)))
828 ;; tailproc gets the result of the last successful process in
829 ;; the pipeline.
830 (setq tailproc (or result tailproc))
831 ,(if (cdr pipeline)
832 `(eshell-do-pipelines-synchronously (quote ,(cdr pipeline))))
833 result))))
835 (defalias 'eshell-process-identity 'identity)
837 (defmacro eshell-execute-pipeline (pipeline)
838 "Execute the commands in PIPELINE, connecting each to one another."
839 `(let ((eshell-in-pipeline-p t) tailproc)
840 (progn
841 ,(if (fboundp 'make-process)
842 `(eshell-do-pipelines ,pipeline)
843 `(let ((tail-handles (eshell-create-handles
844 (car (aref eshell-current-handles
845 ,eshell-output-handle)) nil
846 (car (aref eshell-current-handles
847 ,eshell-error-handle)) nil)))
848 (eshell-do-pipelines-synchronously ,pipeline)))
849 (eshell-process-identity tailproc))))
851 (defmacro eshell-as-subcommand (command)
852 "Execute COMMAND using a temp buffer.
853 This is used so that certain Lisp commands, such as `cd', when
854 executed in a subshell, do not disturb the environment of the main
855 Eshell buffer."
856 `(let ,eshell-subcommand-bindings
857 ,command))
859 (defmacro eshell-do-command-to-value (object)
860 "Run a subcommand prepared by `eshell-command-to-value'.
861 This avoids the need to use `let*'."
862 `(let ((eshell-current-handles
863 (eshell-create-handles value 'overwrite)))
864 (progn
865 ,object
866 (symbol-value value))))
868 (defmacro eshell-command-to-value (object)
869 "Run OBJECT synchronously, returning its result as a string.
870 Returns a string comprising the output from the command."
871 `(let ((value (make-symbol "eshell-temp")))
872 (eshell-do-command-to-value ,object)))
874 ;;;_* Iterative evaluation
876 ;; Eshell runs all of its external commands asynchronously, so that
877 ;; Emacs is not blocked while the operation is being performed.
878 ;; However, this introduces certain synchronization difficulties,
879 ;; since the Lisp code, once it returns, will not "go back" to finish
880 ;; executing the commands which haven't yet been started.
882 ;; What Eshell does to work around this problem (basically, the lack
883 ;; of threads in Lisp), is that it evaluates the command sequence
884 ;; iteratively. Whenever an asynchronous process is begun, evaluation
885 ;; terminates and control is given back to Emacs. When that process
886 ;; finishes, it will resume the evaluation using the remainder of the
887 ;; command tree.
889 (defun eshell/eshell-debug (&rest args)
890 "A command for toggling certain debug variables."
891 (ignore
892 (cond
893 ((not args)
894 (if eshell-handle-errors
895 (eshell-print "errors\n"))
896 (if eshell-debug-command
897 (eshell-print "commands\n")))
898 ((member (car args) '("-h" "--help"))
899 (eshell-print "usage: eshell-debug [kinds]
901 This command is used to aid in debugging problems related to Eshell
902 itself. It is not useful for anything else. The recognized `kinds'
903 at the moment are:
905 errors stops Eshell from trapping errors
906 commands shows command execution progress in `*eshell last cmd*'
909 (while args
910 (cond
911 ((string= (car args) "errors")
912 (setq eshell-handle-errors (not eshell-handle-errors)))
913 ((string= (car args) "commands")
914 (setq eshell-debug-command (not eshell-debug-command))))
915 (setq args (cdr args)))))))
917 (defun pcomplete/eshell-mode/eshell-debug ()
918 "Completion for the `debug' command."
919 (while (pcomplete-here '("errors" "commands"))))
921 (defun eshell-invoke-directly (command)
922 (let ((base (cadr (nth 2 (nth 2 (cadr command))))) name)
923 (if (and (eq (car base) 'eshell-trap-errors)
924 (eq (car (cadr base)) 'eshell-named-command))
925 (setq name (cadr (cadr base))))
926 (and name (stringp name)
927 (not (member name eshell-complex-commands))
928 (catch 'simple
929 (progn
930 (dolist (pred eshell-complex-commands)
931 (if (and (functionp pred)
932 (funcall pred name))
933 (throw 'simple nil)))
935 (fboundp (intern-soft (concat "eshell/" name))))))
937 (defun eshell-eval-command (command &optional input)
938 "Evaluate the given COMMAND iteratively."
939 (if eshell-current-command
940 ;; we can just stick the new command at the end of the current
941 ;; one, and everything will happen as it should
942 (setcdr (last (cdr eshell-current-command))
943 (list `(let ((here (and (eobp) (point))))
944 ,(and input
945 `(insert-and-inherit ,(concat input "\n")))
946 (if here
947 (eshell-update-markers here))
948 (eshell-do-eval ',command))))
949 (and eshell-debug-command
950 (with-current-buffer (get-buffer-create "*eshell last cmd*")
951 (erase-buffer)
952 (insert "command: \"" input "\"\n")))
953 (setq eshell-current-command command)
954 (let ((delim (catch 'eshell-incomplete
955 (eshell-resume-eval))))
956 ;; On systems that don't support async subprocesses, eshell-resume
957 ;; can return t. Don't treat that as an error.
958 (if (listp delim)
959 (setq delim (car delim)))
960 (if (and delim (not (eq delim t)))
961 (error "Unmatched delimiter: %c" delim)))))
963 (defun eshell-resume-command (proc status)
964 "Resume the current command when a process ends."
965 (when proc
966 (unless (or (not (stringp status))
967 (string= "stopped" status)
968 (string-match eshell-reset-signals status))
969 (if (eq proc (eshell-interactive-process))
970 (eshell-resume-eval)))))
972 (defun eshell-resume-eval ()
973 "Destructively evaluate a form which may need to be deferred."
974 (eshell-condition-case err
975 (progn
976 (setq eshell-last-async-proc nil)
977 (when eshell-current-command
978 (let* (retval
979 (proc (catch 'eshell-defer
980 (ignore
981 (setq retval
982 (eshell-do-eval
983 eshell-current-command))))))
984 (if (eshell-processp proc)
985 (ignore (setq eshell-last-async-proc proc))
986 (cadr retval)))))
987 (error
988 (error (error-message-string err)))))
990 (defmacro eshell-manipulate (tag &rest commands)
991 "Manipulate a COMMAND form, with TAG as a debug identifier."
992 (declare (indent 1))
993 ;; Check `bound'ness since at compile time the code until here has not
994 ;; executed yet.
995 (if (not (and (boundp 'eshell-debug-command) eshell-debug-command))
996 `(progn ,@commands)
997 `(progn
998 (eshell-debug-command ,(eval tag) form)
999 ,@commands
1000 (eshell-debug-command ,(concat "done " (eval tag)) form))))
1002 (defun eshell-do-eval (form &optional synchronous-p)
1003 "Evaluate form, simplifying it as we go.
1004 Unless SYNCHRONOUS-P is non-nil, throws `eshell-defer' if it needs to
1005 be finished later after the completion of an asynchronous subprocess."
1006 (cond
1007 ((not (listp form))
1008 (list 'quote (eval form)))
1009 ((memq (car form) '(quote function))
1010 form)
1012 ;; skip past the call to `eshell-do-eval'
1013 (when (eq (car form) 'eshell-do-eval)
1014 (setq form (cadr (cadr form))))
1015 ;; expand any macros directly into the form. This is done so that
1016 ;; we can modify any `let' forms to evaluate only once.
1017 (if (macrop (car form))
1018 (let ((exp (eshell-copy-tree (macroexpand form))))
1019 (eshell-manipulate (format-message "expanding macro `%s'"
1020 (symbol-name (car form)))
1021 (setcar form (car exp))
1022 (setcdr form (cdr exp)))))
1023 (let ((args (cdr form)))
1024 (cond
1025 ((eq (car form) 'while)
1026 ;; `eshell-copy-tree' is needed here so that the test argument
1027 ;; doesn't get modified and thus always yield the same result.
1028 (when (car eshell-command-body)
1029 (cl-assert (not synchronous-p))
1030 (eshell-do-eval (car eshell-command-body))
1031 (setcar eshell-command-body nil)
1032 (setcar eshell-test-body nil))
1033 (unless (car eshell-test-body)
1034 (setcar eshell-test-body (eshell-copy-tree (car args))))
1035 (while (cadr (eshell-do-eval (car eshell-test-body)))
1036 (setcar eshell-command-body
1037 (if (cddr args)
1038 `(progn ,@(eshell-copy-tree (cdr args)))
1039 (eshell-copy-tree (cadr args))))
1040 (eshell-do-eval (car eshell-command-body) synchronous-p)
1041 (setcar eshell-command-body nil)
1042 (setcar eshell-test-body (eshell-copy-tree (car args))))
1043 (setcar eshell-command-body nil))
1044 ((eq (car form) 'if)
1045 ;; `eshell-copy-tree' is needed here so that the test argument
1046 ;; doesn't get modified and thus always yield the same result.
1047 (if (car eshell-command-body)
1048 (progn
1049 (cl-assert (not synchronous-p))
1050 (eshell-do-eval (car eshell-command-body)))
1051 (unless (car eshell-test-body)
1052 (setcar eshell-test-body (eshell-copy-tree (car args))))
1053 (setcar eshell-command-body
1054 (eshell-copy-tree
1055 (if (cadr (eshell-do-eval (car eshell-test-body)))
1056 (cadr args)
1057 (car (cddr args)))))
1058 (eshell-do-eval (car eshell-command-body) synchronous-p))
1059 (setcar eshell-command-body nil)
1060 (setcar eshell-test-body nil))
1061 ((eq (car form) 'setcar)
1062 (setcar (cdr args) (eshell-do-eval (cadr args) synchronous-p))
1063 (eval form))
1064 ((eq (car form) 'setcdr)
1065 (setcar (cdr args) (eshell-do-eval (cadr args) synchronous-p))
1066 (eval form))
1067 ((memq (car form) '(let catch condition-case unwind-protect))
1068 ;; `let', `condition-case' and `unwind-protect' have to be
1069 ;; handled specially, because we only want to call
1070 ;; `eshell-do-eval' on their first form.
1072 ;; NOTE: This requires obedience by all forms which this
1073 ;; function might encounter, that they do not contain
1074 ;; other special forms.
1075 (if (and (eq (car form) 'let)
1076 (not (eq (car (cadr args)) 'eshell-do-eval)))
1077 (eshell-manipulate "evaluating let args"
1078 (dolist (letarg (car args))
1079 (if (and (listp letarg)
1080 (not (eq (cadr letarg) 'quote)))
1081 (setcdr letarg
1082 (list (eshell-do-eval
1083 (cadr letarg) synchronous-p)))))))
1084 (unless (eq (car form) 'unwind-protect)
1085 (setq args (cdr args)))
1086 (unless (eq (caar args) 'eshell-do-eval)
1087 (eshell-manipulate "handling special form"
1088 (setcar args `(eshell-do-eval ',(car args) ,synchronous-p))))
1089 (eval form))
1090 ((eq (car form) 'setq)
1091 (if (cddr args) (error "Unsupported form (setq X1 E1 X2 E2..)"))
1092 (eshell-manipulate "evaluating arguments to setq"
1093 (setcar (cdr args) (eshell-do-eval (cadr args) synchronous-p)))
1094 (list 'quote (eval form)))
1096 (if (and args (not (memq (car form) '(run-hooks))))
1097 (eshell-manipulate
1098 (format-message "evaluating arguments to `%s'"
1099 (symbol-name (car form)))
1100 (while args
1101 (setcar args (eshell-do-eval (car args) synchronous-p))
1102 (setq args (cdr args)))))
1103 (cond
1104 ((eq (car form) 'progn)
1105 (car (last form)))
1106 ((eq (car form) 'prog1)
1107 (cadr form))
1109 ;; If a command desire to replace its execution form with
1110 ;; another command form, all it needs to do is throw the new
1111 ;; form using the exception tag `eshell-replace-command'.
1112 ;; For example, let's say that the form currently being
1113 ;; eval'd is:
1115 ;; (eshell-named-command "hello")
1117 ;; Now, let's assume the 'hello' command is an Eshell alias,
1118 ;; the definition of which yields the command:
1120 ;; (eshell-named-command "echo" (list "Hello" "world"))
1122 ;; What the alias code would like to do is simply substitute
1123 ;; the alias form for the original form. To accomplish
1124 ;; this, all it needs to do is to throw the substitution
1125 ;; form with the `eshell-replace-command' tag, and the form
1126 ;; will be replaced within the current command, and
1127 ;; execution will then resume (iteratively) as before.
1128 ;; Thus, aliases can even contain references to asynchronous
1129 ;; sub-commands, and things will still work out as they
1130 ;; should.
1131 (let* (result
1132 (new-form
1133 (catch 'eshell-replace-command
1134 (ignore
1135 (setq result (eval form))))))
1136 (if new-form
1137 (progn
1138 (eshell-manipulate "substituting replacement form"
1139 (setcar form (car new-form))
1140 (setcdr form (cdr new-form)))
1141 (eshell-do-eval form synchronous-p))
1142 (if (and (memq (car form) eshell-deferrable-commands)
1143 (not eshell-current-subjob-p)
1144 result
1145 (eshell-processp result))
1146 (if synchronous-p
1147 (eshell/wait result)
1148 (eshell-manipulate "inserting ignore form"
1149 (setcar form 'ignore)
1150 (setcdr form nil))
1151 (throw 'eshell-defer result))
1152 (list 'quote result))))))))))))
1154 ;; command invocation
1156 (defun eshell/which (command &rest names)
1157 "Identify the COMMAND, and where it is located."
1158 (dolist (name (cons command names))
1159 (let (program alias direct)
1160 (if (eq (aref name 0) eshell-explicit-command-char)
1161 (setq name (substring name 1)
1162 direct t))
1163 (if (and (not direct)
1164 (eshell-using-module 'eshell-alias)
1165 (setq alias
1166 (funcall (symbol-function 'eshell-lookup-alias)
1167 name)))
1168 (setq program
1169 (concat name " is an alias, defined as \""
1170 (cadr alias) "\"")))
1171 (unless program
1172 (setq program (eshell-search-path name))
1173 (let* ((esym (eshell-find-alias-function name))
1174 (sym (or esym (intern-soft name))))
1175 (if (and (or esym (and sym (fboundp sym)))
1176 (or eshell-prefer-lisp-functions (not direct)))
1177 (let ((desc (let ((inhibit-redisplay t))
1178 (save-window-excursion
1179 (prog1
1180 (describe-function sym)
1181 (message nil))))))
1182 (setq desc (if desc (substring desc 0
1183 (1- (or (string-match "\n" desc)
1184 (length desc))))
1185 ;; This should not happen.
1186 (format "%s is defined, \
1187 but no documentation was found" name)))
1188 (if (buffer-live-p (get-buffer "*Help*"))
1189 (kill-buffer "*Help*"))
1190 (setq program (or desc name))))))
1191 (if (not program)
1192 (eshell-error (format "which: no %s in (%s)\n"
1193 name (getenv "PATH")))
1194 (eshell-printn program)))))
1196 (put 'eshell/which 'eshell-no-numeric-conversions t)
1198 (defun eshell-named-command (command &optional args)
1199 "Insert output from a plain COMMAND, using ARGS.
1200 COMMAND may result in an alias being executed, or a plain command."
1201 (setq eshell-last-arguments args
1202 eshell-last-command-name (eshell-stringify command))
1203 (run-hook-with-args 'eshell-prepare-command-hook)
1204 (cl-assert (stringp eshell-last-command-name))
1205 (if eshell-last-command-name
1206 (or (run-hook-with-args-until-success
1207 'eshell-named-command-hook eshell-last-command-name
1208 eshell-last-arguments)
1209 (eshell-plain-command eshell-last-command-name
1210 eshell-last-arguments))))
1212 (defalias 'eshell-named-command* 'eshell-named-command)
1214 (defun eshell-find-alias-function (name)
1215 "Check whether a function called `eshell/NAME' exists."
1216 (let* ((sym (intern-soft (concat "eshell/" name)))
1217 (file (symbol-file sym 'defun)))
1218 ;; If the function exists, but is defined in an eshell module
1219 ;; that's not currently enabled, don't report it as found.
1220 (if (and file
1221 (setq file (file-name-base file))
1222 (string-match "\\`\\(em\\|esh\\)-\\([[:alnum:]]+\\)\\'" file))
1223 (let ((module-sym
1224 (intern (concat "eshell-" (match-string 2 file)))))
1225 (if (and (functionp sym)
1226 (or (null module-sym)
1227 (eshell-using-module module-sym)
1228 (memq module-sym (eshell-subgroups 'eshell))))
1229 sym))
1230 ;; Otherwise, if it's bound, return it.
1231 (if (functionp sym)
1232 sym))))
1234 (defun eshell-plain-command (command args)
1235 "Insert output from a plain COMMAND, using ARGS.
1236 COMMAND may result in either a Lisp function being executed by name,
1237 or an external command."
1238 (let* ((esym (eshell-find-alias-function command))
1239 (sym (or esym (intern-soft command))))
1240 (if (and sym (fboundp sym)
1241 (or esym eshell-prefer-lisp-functions
1242 (not (eshell-search-path command))))
1243 (eshell-lisp-command sym args)
1244 (eshell-external-command command args))))
1246 (defun eshell-exec-lisp (printer errprint func-or-form args form-p)
1247 "Execute a lisp FUNC-OR-FORM, maybe passing ARGS.
1248 PRINTER and ERRPRINT are functions to use for printing regular
1249 messages, and errors. FORM-P should be non-nil if FUNC-OR-FORM
1250 represent a lisp form; ARGS will be ignored in that case."
1251 (eshell-condition-case err
1252 (let ((result
1253 (save-current-buffer
1254 (if form-p
1255 (eval func-or-form)
1256 (apply func-or-form args)))))
1257 (and result (funcall printer result))
1258 result)
1259 (error
1260 (let ((msg (error-message-string err)))
1261 (if (and (not form-p)
1262 (string-match "^Wrong number of arguments" msg)
1263 (fboundp 'eldoc-get-fnsym-args-string))
1264 (let ((func-doc (eldoc-get-fnsym-args-string func-or-form)))
1265 (setq msg (format "usage: %s" func-doc))))
1266 (funcall errprint msg))
1267 nil)))
1269 (defsubst eshell-apply* (printer errprint func args)
1270 "Call FUNC, with ARGS, trapping errors and return them as output.
1271 PRINTER and ERRPRINT are functions to use for printing regular
1272 messages, and errors."
1273 (eshell-exec-lisp printer errprint func args nil))
1275 (defsubst eshell-funcall* (printer errprint func &rest args)
1276 "Call FUNC, with ARGS, trapping errors and return them as output."
1277 (eshell-apply* printer errprint func args))
1279 (defsubst eshell-eval* (printer errprint form)
1280 "Evaluate FORM, trapping errors and returning them."
1281 (eshell-exec-lisp printer errprint form nil t))
1283 (defsubst eshell-apply (func args)
1284 "Call FUNC, with ARGS, trapping errors and return them as output.
1285 PRINTER and ERRPRINT are functions to use for printing regular
1286 messages, and errors."
1287 (eshell-apply* 'eshell-print 'eshell-error func args))
1289 (defsubst eshell-funcall (func &rest args)
1290 "Call FUNC, with ARGS, trapping errors and return them as output."
1291 (eshell-apply func args))
1293 (defsubst eshell-eval (form)
1294 "Evaluate FORM, trapping errors and returning them."
1295 (eshell-eval* 'eshell-print 'eshell-error form))
1297 (defsubst eshell-applyn (func args)
1298 "Call FUNC, with ARGS, trapping errors and return them as output.
1299 PRINTER and ERRPRINT are functions to use for printing regular
1300 messages, and errors."
1301 (eshell-apply* 'eshell-printn 'eshell-errorn func args))
1303 (defsubst eshell-funcalln (func &rest args)
1304 "Call FUNC, with ARGS, trapping errors and return them as output."
1305 (eshell-applyn func args))
1307 (defsubst eshell-evaln (form)
1308 "Evaluate FORM, trapping errors and returning them."
1309 (eshell-eval* 'eshell-printn 'eshell-errorn form))
1311 (defvar eshell-last-output-end) ;Defined in esh-mode.el.
1313 (defun eshell-lisp-command (object &optional args)
1314 "Insert Lisp OBJECT, using ARGS if a function."
1315 (catch 'eshell-external ; deferred to an external command
1316 (let* ((eshell-ensure-newline-p (eshell-interactive-output-p))
1317 (result
1318 (if (functionp object)
1319 (progn
1320 (setq eshell-last-arguments args
1321 eshell-last-command-name
1322 (concat "#<function " (symbol-name object) ">"))
1323 ;; if any of the arguments are flagged as numbers
1324 ;; waiting for conversion, convert them now
1325 (unless (get object 'eshell-no-numeric-conversions)
1326 (while args
1327 (let ((arg (car args)))
1328 (if (and (stringp arg)
1329 (> (length arg) 0)
1330 (not (text-property-not-all
1331 0 (length arg) 'number t arg)))
1332 (setcar args (string-to-number arg))))
1333 (setq args (cdr args))))
1334 (eshell-apply object eshell-last-arguments))
1335 (setq eshell-last-arguments args
1336 eshell-last-command-name "#<Lisp object>")
1337 (eshell-eval object))))
1338 (if (and eshell-ensure-newline-p
1339 (save-excursion
1340 (goto-char eshell-last-output-end)
1341 (not (bolp))))
1342 (eshell-print "\n"))
1343 (eshell-close-handles 0 (list 'quote result)))))
1345 (defalias 'eshell-lisp-command* 'eshell-lisp-command)
1347 (provide 'esh-cmd)
1349 ;;; esh-cmd.el ends here