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73804d4b | 1 | @comment -*-texinfo-*- |
969fe9b5 RS |
2 | @c This is part of the GNU Emacs Lisp Reference Manual. |
3 | @c Copyright (C) 1992, 1993, 1994, 1998 Free Software Foundation, Inc. | |
4 | @c See the file elisp.texi for copying conditions. | |
73804d4b | 5 | |
969fe9b5 RS |
6 | @c This file can also be used by an independent Edebug User |
7 | @c Manual in which case the Edebug node below should be used | |
73804d4b RS |
8 | @c with the following links to the Bugs section and to the top level: |
9 | ||
10 | @c , Bugs and Todo List, Top, Top | |
11 | ||
1911e6e5 | 12 | @node Edebug, Syntax Errors, Debugger, Debugging |
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13 | @section Edebug |
14 | @cindex Edebug mode | |
15 | ||
16 | @cindex Edebug | |
17 | Edebug is a source-level debugger for Emacs Lisp programs with which | |
18 | you can: | |
19 | ||
20 | @itemize @bullet | |
21 | @item | |
22 | Step through evaluation, stopping before and after each expression. | |
23 | ||
24 | @item | |
25 | Set conditional or unconditional breakpoints. | |
26 | ||
27 | @item | |
28 | Stop when a specified condition is true (the global break event). | |
29 | ||
30 | @item | |
31 | Trace slow or fast, stopping briefly at each stop point, or | |
32 | at each breakpoint. | |
33 | ||
34 | @item | |
35 | Display expression results and evaluate expressions as if outside of | |
36 | Edebug. | |
37 | ||
38 | @item | |
a9f0a989 | 39 | Automatically re-evaluate a list of expressions and |
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40 | display their results each time Edebug updates the display. |
41 | ||
42 | @item | |
43 | Output trace info on function enter and exit. | |
44 | ||
45 | @item | |
46 | Stop when an error occurs. | |
47 | ||
48 | @item | |
49 | Display a backtrace, omitting Edebug's own frames. | |
50 | ||
51 | @item | |
52 | Specify argument evaluation for macros and defining forms. | |
53 | ||
54 | @item | |
55 | Obtain rudimentary coverage testing and frequency counts. | |
56 | @end itemize | |
57 | ||
58 | The first three sections below should tell you enough about Edebug to | |
59 | enable you to use it. | |
60 | ||
61 | @menu | |
62 | * Using Edebug:: Introduction to use of Edebug. | |
63 | * Instrumenting:: You must instrument your code | |
64 | in order to debug it with Edebug. | |
65 | * Modes: Edebug Execution Modes. Execution modes, stopping more or less often. | |
66 | * Jumping:: Commands to jump to a specified place. | |
67 | * Misc: Edebug Misc. Miscellaneous commands. | |
68 | * Breakpoints:: Setting breakpoints to make the program stop. | |
69 | * Trapping Errors:: trapping errors with Edebug. | |
70 | * Views: Edebug Views. Views inside and outside of Edebug. | |
71 | * Eval: Edebug Eval. Evaluating expressions within Edebug. | |
72 | * Eval List:: Expressions whose values are displayed | |
73 | each time you enter Edebug. | |
74 | * Printing in Edebug:: Customization of printing. | |
75 | * Trace Buffer:: How to produce trace output in a buffer. | |
76 | * Coverage Testing:: How to test evaluation coverage. | |
77 | * The Outside Context:: Data that Edebug saves and restores. | |
78 | * Instrumenting Macro Calls:: Specifying how to handle macro calls. | |
79 | * Options: Edebug Options. Option variables for customizing Edebug. | |
80 | @end menu | |
81 | ||
82 | @node Using Edebug | |
83 | @subsection Using Edebug | |
84 | ||
85 | To debug a Lisp program with Edebug, you must first @dfn{instrument} | |
86 | the Lisp code that you want to debug. A simple way to do this is to | |
87 | first move point into the definition of a function or macro and then do | |
88 | @kbd{C-u C-M-x} (@code{eval-defun} with a prefix argument). See | |
89 | @ref{Instrumenting}, for alternative ways to instrument code. | |
90 | ||
91 | Once a function is instrumented, any call to the function activates | |
92 | Edebug. Activating Edebug may stop execution and let you step through | |
93 | the function, or it may update the display and continue execution while | |
94 | checking for debugging commands, depending on which Edebug execution | |
95 | mode you have selected. The default execution mode is step, which does | |
96 | stop execution. @xref{Edebug Execution Modes}. | |
97 | ||
98 | Within Edebug, you normally view an Emacs buffer showing the source of | |
99 | the Lisp code you are debugging. This is referred to as the @dfn{source | |
100 | code buffer}. This buffer is temporarily read-only. | |
101 | ||
102 | An arrow at the left margin indicates the line where the function is | |
103 | executing. Point initially shows where within the line the function is | |
104 | executing, but this ceases to be true if you move point yourself. | |
105 | ||
106 | If you instrument the definition of @code{fac} (shown below) and then | |
107 | execute @code{(fac 3)}, here is what you normally see. Point is at the | |
108 | open-parenthesis before @code{if}. | |
109 | ||
110 | @example | |
111 | (defun fac (n) | |
112 | =>@point{}(if (< 0 n) | |
113 | (* n (fac (1- n))) | |
114 | 1)) | |
115 | @end example | |
116 | ||
117 | @cindex stop points | |
118 | The places within a function where Edebug can stop execution are called | |
119 | @dfn{stop points}. These occur both before and after each subexpression | |
120 | that is a list, and also after each variable reference. | |
121 | Here we show with periods the stop points found in the function | |
122 | @code{fac}: | |
123 | ||
124 | @example | |
125 | (defun fac (n) | |
126 | .(if .(< 0 n.). | |
127 | .(* n. .(fac (1- n.).).). | |
128 | 1).) | |
129 | @end example | |
130 | ||
131 | The special commands of Edebug are available in the source code buffer | |
132 | in addition to the commands of Emacs Lisp mode. For example, you can | |
133 | type the Edebug command @key{SPC} to execute until the next stop point. | |
134 | If you type @key{SPC} once after entry to @code{fac}, here is the | |
135 | display you will see: | |
136 | ||
137 | @example | |
138 | (defun fac (n) | |
139 | =>(if @point{}(< 0 n) | |
140 | (* n (fac (1- n))) | |
141 | 1)) | |
142 | @end example | |
143 | ||
144 | When Edebug stops execution after an expression, it displays the | |
145 | expression's value in the echo area. | |
146 | ||
147 | Other frequently used commands are @kbd{b} to set a breakpoint at a stop | |
148 | point, @kbd{g} to execute until a breakpoint is reached, and @kbd{q} to | |
149 | exit Edebug and return to the top-level command loop. Type @kbd{?} to | |
150 | display a list of all Edebug commands. | |
151 | ||
152 | @node Instrumenting | |
153 | @subsection Instrumenting for Edebug | |
154 | ||
155 | In order to use Edebug to debug Lisp code, you must first | |
156 | @dfn{instrument} the code. Instrumenting code inserts additional code | |
87b2d5ff | 157 | into it, to invoke Edebug at the proper places. |
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158 | |
159 | @kindex C-M-x | |
160 | @findex eval-defun (Edebug) | |
161 | Once you have loaded Edebug, the command @kbd{C-M-x} | |
162 | (@code{eval-defun}) is redefined so that when invoked with a prefix | |
163 | argument on a definition, it instruments the definition before | |
164 | evaluating it. (The source code itself is not modified.) If the | |
165 | variable @code{edebug-all-defs} is non-@code{nil}, that inverts the | |
166 | meaning of the prefix argument: then @kbd{C-M-x} instruments the | |
167 | definition @emph{unless} it has a prefix argument. The default value of | |
168 | @code{edebug-all-defs} is @code{nil}. The command @kbd{M-x | |
169 | edebug-all-defs} toggles the value of the variable | |
170 | @code{edebug-all-defs}. | |
171 | ||
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172 | @findex eval-region @r{(Edebug)} |
173 | @findex eval-current-buffer @r{(Edebug)} | |
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174 | If @code{edebug-all-defs} is non-@code{nil}, then the commands |
175 | @code{eval-region}, @code{eval-current-buffer}, and @code{eval-buffer} | |
176 | also instrument any definitions they evaluate. Similarly, | |
177 | @code{edebug-all-forms} controls whether @code{eval-region} should | |
178 | instrument @emph{any} form, even non-defining forms. This doesn't apply | |
179 | to loading or evaluations in the minibuffer. The command @kbd{M-x | |
180 | edebug-all-forms} toggles this option. | |
181 | ||
182 | @findex edebug-eval-top-level-form | |
969fe9b5 | 183 | Another command, @kbd{M-x edebug-eval-top-level-form}, is available to |
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184 | instrument any top-level form regardless of the values of |
185 | @code{edebug-all-defs} and @code{edebug-all-forms}. | |
73804d4b | 186 | |
969fe9b5 | 187 | While Edebug is active, the command @kbd{I} |
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188 | (@code{edebug-instrument-callee}) instruments the definition of the |
189 | function or macro called by the list form after point, if is not already | |
190 | instrumented. This is possible only if Edebug knows where to find the | |
191 | source for that function; after loading Edebug, @code{eval-region} | |
192 | records the position of every definition it evaluates, even if not | |
193 | instrumenting it. See also the @kbd{i} command (@pxref{Jumping}), which | |
194 | steps into the call after instrumenting the function. | |
195 | ||
196 | @cindex special forms (Edebug) | |
197 | @cindex interactive commands (Edebug) | |
198 | @cindex anonymous lambda expressions (Edebug) | |
199 | @cindex Common Lisp (Edebug) | |
969fe9b5 | 200 | @pindex cl.el @r{(Edebug)} |
73804d4b | 201 | @pindex cl-specs.el |
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202 | Edebug knows how to instrument all the standard special forms, |
203 | @code{interactive} forms with an expression argument, anonymous lambda | |
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204 | expressions, and other defining forms. Edebug cannot know what a |
205 | user-defined macro will do with the arguments of a macro call, so you | |
a9f0a989 | 206 | must tell it; see @ref{Instrumenting Macro Calls}, for details. |
73804d4b | 207 | |
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208 | When Edebug is about to instrument code for the first time in a |
209 | session, it runs the hook @code{edebug-setup-hook}, then sets it to | |
210 | @code{nil}. You can use this to arrange to load Edebug specifications | |
211 | (@pxref{Instrumenting Macro Calls}) associated with a package you are | |
212 | using, but actually load them only if you use Edebug. | |
213 | ||
214 | @findex eval-expression @r{(Edebug)} | |
a9f0a989 | 215 | To remove instrumentation from a definition, simply re-evaluate its |
73804d4b | 216 | definition in a way that does not instrument. There are two ways of |
87b2d5ff | 217 | evaluating forms that never instrument them: from a file with |
73804d4b | 218 | @code{load}, and from the minibuffer with @code{eval-expression} |
bfe721d1 | 219 | (@kbd{M-:}). |
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220 | |
221 | If Edebug detects a syntax error while instrumenting, it leaves point | |
222 | at the erroneous code and signals an @code{invalid-read-syntax} error. | |
223 | ||
224 | @xref{Edebug Eval}, for other evaluation functions available | |
225 | inside of Edebug. | |
226 | ||
227 | @node Edebug Execution Modes | |
228 | @subsection Edebug Execution Modes | |
229 | ||
230 | @cindex Edebug execution modes | |
231 | Edebug supports several execution modes for running the program you are | |
232 | debugging. We call these alternatives @dfn{Edebug execution modes}; do | |
87b2d5ff | 233 | not confuse them with major or minor modes. The current Edebug execution mode |
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234 | determines how far Edebug continues execution before stopping---whether |
235 | it stops at each stop point, or continues to the next breakpoint, for | |
236 | example---and how much Edebug displays the progress of the evaluation | |
237 | before it stops. | |
238 | ||
239 | Normally, you specify the Edebug execution mode by typing a command to | |
240 | continue the program in a certain mode. Here is a table of these | |
241 | commands. All except for @kbd{S} resume execution of the program, at | |
242 | least for a certain distance. | |
243 | ||
244 | @table @kbd | |
245 | @item S | |
246 | Stop: don't execute any more of the program for now, just wait for more | |
247 | Edebug commands (@code{edebug-stop}). | |
248 | ||
249 | @item @key{SPC} | |
250 | Step: stop at the next stop point encountered (@code{edebug-step-mode}). | |
251 | ||
252 | @item n | |
253 | Next: stop at the next stop point encountered after an expression | |
254 | (@code{edebug-next-mode}). Also see @code{edebug-forward-sexp} in | |
255 | @ref{Edebug Misc}. | |
256 | ||
257 | @item t | |
258 | Trace: pause one second at each Edebug stop point (@code{edebug-trace-mode}). | |
259 | ||
260 | @item T | |
261 | Rapid trace: update the display at each stop point, but don't actually | |
262 | pause (@code{edebug-Trace-fast-mode}). | |
263 | ||
264 | @item g | |
265 | Go: run until the next breakpoint (@code{edebug-go-mode}). @xref{Breakpoints}. | |
266 | ||
267 | @item c | |
268 | Continue: pause one second at each breakpoint, and then continue | |
269 | (@code{edebug-continue-mode}). | |
270 | ||
271 | @item C | |
272 | Rapid continue: move point to each breakpoint, but don't pause | |
273 | (@code{edebug-Continue-fast-mode}). | |
274 | ||
275 | @item G | |
276 | Go non-stop: ignore breakpoints (@code{edebug-Go-nonstop-mode}). You | |
277 | can still stop the program by typing @kbd{S}, or any editing command. | |
278 | @end table | |
279 | ||
280 | In general, the execution modes earlier in the above list run the | |
87b2d5ff | 281 | program more slowly or stop sooner than the modes later in the list. |
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282 | |
283 | While executing or tracing, you can interrupt the execution by typing | |
284 | any Edebug command. Edebug stops the program at the next stop point and | |
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285 | then executes the command you typed. For example, typing @kbd{t} during |
286 | execution switches to trace mode at the next stop point. You can use | |
287 | @kbd{S} to stop execution without doing anything else. | |
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288 | |
289 | If your function happens to read input, a character you type intending | |
290 | to interrupt execution may be read by the function instead. You can | |
291 | avoid such unintended results by paying attention to when your program | |
292 | wants input. | |
293 | ||
294 | @cindex keyboard macros (Edebug) | |
295 | Keyboard macros containing the commands in this section do not | |
296 | completely work: exiting from Edebug, to resume the program, loses track | |
297 | of the keyboard macro. This is not easy to fix. Also, defining or | |
298 | executing a keyboard macro outside of Edebug does not affect commands | |
299 | inside Edebug. This is usually an advantage. But see the | |
300 | @code{edebug-continue-kbd-macro} option (@pxref{Edebug Options}). | |
301 | ||
302 | When you enter a new Edebug level, the initial execution mode comes from | |
303 | the value of the variable @code{edebug-initial-mode}. By default, this | |
304 | specifies step mode. Note that you may reenter the same Edebug level | |
305 | several times if, for example, an instrumented function is called | |
306 | several times from one command. | |
307 | ||
308 | ||
309 | @node Jumping | |
310 | @subsection Jumping | |
311 | ||
312 | The commands described in this section execute until they reach a | |
313 | specified location. All except @kbd{i} make a temporary breakpoint to | |
314 | establish the place to stop, then switch to go mode. Any other | |
315 | breakpoint reached before the intended stop point will also stop | |
316 | execution. @xref{Breakpoints}, for the details on breakpoints. | |
317 | ||
318 | These commands may fail to work as expected in case of nonlocal exit, | |
319 | because a nonlocal exit can bypass the temporary breakpoint where you | |
320 | expected the program to stop. | |
321 | ||
322 | @table @kbd | |
323 | @item h | |
324 | Proceed to the stop point near where point is (@code{edebug-goto-here}). | |
325 | ||
326 | @item f | |
327 | Run the program forward over one expression | |
328 | (@code{edebug-forward-sexp}). | |
329 | ||
330 | @item o | |
331 | Run the program until the end of the containing sexp. | |
332 | ||
333 | @item i | |
334 | Step into the function or macro called by the form after point. | |
335 | @end table | |
336 | ||
337 | The @kbd{h} command proceeds to the stop point near the current location | |
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338 | of point, using a temporary breakpoint. See @ref{Breakpoints}, for more |
339 | information about breakpoints. | |
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340 | |
341 | The @kbd{f} command runs the program forward over one expression. More | |
342 | precisely, it sets a temporary breakpoint at the position that | |
343 | @kbd{C-M-f} would reach, then executes in go mode so that the program | |
344 | will stop at breakpoints. | |
345 | ||
346 | With a prefix argument @var{n}, the temporary breakpoint is placed | |
347 | @var{n} sexps beyond point. If the containing list ends before @var{n} | |
348 | more elements, then the place to stop is after the containing | |
349 | expression. | |
350 | ||
351 | Be careful that the position @kbd{C-M-f} finds is a place that the | |
352 | program will really get to; this may not be true in a | |
353 | @code{cond}, for example. | |
354 | ||
355 | The @kbd{f} command does @code{forward-sexp} starting at point, rather | |
356 | than at the stop point, for flexibility. If you want to execute one | |
357 | expression @emph{from the current stop point}, type @kbd{w} first, to | |
358 | move point there, and then type @kbd{f}. | |
359 | ||
360 | The @kbd{o} command continues ``out of'' an expression. It places a | |
361 | temporary breakpoint at the end of the sexp containing point. If the | |
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362 | containing sexp is a function definition itself, @kbd{o} continues until |
363 | just before the last sexp in the definition. If that is where you are | |
364 | now, it returns from the function and then stops. In other words, this | |
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365 | command does not exit the currently executing function unless you are |
366 | positioned after the last sexp. | |
367 | ||
368 | The @kbd{i} command steps into the function or macro called by the list | |
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369 | form after point, and stops at its first stop point. Note that the form |
370 | need not be the one about to be evaluated. But if the form is a | |
371 | function call about to be evaluated, remember to use this command before | |
372 | any of the arguments are evaluated, since otherwise it will be too late. | |
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373 | |
374 | The @kbd{i} command instruments the function or macro it's supposed to | |
375 | step into, if it isn't instrumented already. This is convenient, but keep | |
376 | in mind that the function or macro remains instrumented unless you explicitly | |
377 | arrange to deinstrument it. | |
378 | ||
379 | @node Edebug Misc | |
380 | @subsection Miscellaneous Edebug Commands | |
381 | ||
382 | Some miscellaneous Edebug commands are described here. | |
383 | ||
384 | @table @kbd | |
385 | @item ? | |
386 | Display the help message for Edebug (@code{edebug-help}). | |
387 | ||
388 | @item C-] | |
389 | Abort one level back to the previous command level | |
390 | (@code{abort-recursive-edit}). | |
391 | ||
392 | @item q | |
393 | Return to the top level editor command loop (@code{top-level}). This | |
394 | exits all recursive editing levels, including all levels of Edebug | |
395 | activity. However, instrumented code protected with | |
396 | @code{unwind-protect} or @code{condition-case} forms may resume | |
397 | debugging. | |
398 | ||
399 | @item Q | |
400 | Like @kbd{q} but don't stop even for protected code | |
401 | (@code{top-level-nonstop}). | |
402 | ||
403 | @item r | |
404 | Redisplay the most recently known expression result in the echo area | |
405 | (@code{edebug-previous-result}). | |
406 | ||
407 | @item d | |
408 | Display a backtrace, excluding Edebug's own functions for clarity | |
409 | (@code{edebug-backtrace}). | |
410 | ||
411 | You cannot use debugger commands in the backtrace buffer in Edebug as | |
412 | you would in the standard debugger. | |
413 | ||
414 | The backtrace buffer is killed automatically when you continue | |
415 | execution. | |
416 | @end table | |
417 | ||
87b2d5ff | 418 | From the Edebug recursive edit, you may invoke commands that activate |
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419 | Edebug again recursively. Any time Edebug is active, you can quit to |
420 | the top level with @kbd{q} or abort one recursive edit level with | |
421 | @kbd{C-]}. You can display a backtrace of all the | |
422 | pending evaluations with @kbd{d}. | |
423 | ||
424 | @node Breakpoints | |
425 | @subsection Breakpoints | |
426 | ||
427 | @cindex breakpoints | |
428 | Edebug's step mode stops execution at the next stop point reached. | |
429 | There are three other ways to stop Edebug execution once it has started: | |
430 | breakpoints, the global break condition, and source breakpoints. | |
431 | ||
432 | While using Edebug, you can specify @dfn{breakpoints} in the program you | |
433 | are testing: points where execution should stop. You can set a | |
434 | breakpoint at any stop point, as defined in @ref{Using Edebug}. For | |
435 | setting and unsetting breakpoints, the stop point that is affected is | |
436 | the first one at or after point in the source code buffer. Here are the | |
437 | Edebug commands for breakpoints: | |
438 | ||
439 | @table @kbd | |
440 | @item b | |
441 | Set a breakpoint at the stop point at or after point | |
442 | (@code{edebug-set-breakpoint}). If you use a prefix argument, the | |
443 | breakpoint is temporary (it turns off the first time it stops the | |
444 | program). | |
445 | ||
446 | @item u | |
447 | Unset the breakpoint (if any) at the stop point at or after | |
448 | point (@code{edebug-unset-breakpoint}). | |
449 | ||
450 | @item x @var{condition} @key{RET} | |
451 | Set a conditional breakpoint which stops the program only if | |
452 | @var{condition} evaluates to a non-@code{nil} value | |
453 | (@code{edebug-set-conditional-breakpoint}). With a prefix argument, the | |
454 | breakpoint is temporary. | |
455 | ||
456 | @item B | |
9e2b495b | 457 | Move point to the next breakpoint in the current definition |
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458 | (@code{edebug-next-breakpoint}). |
459 | @end table | |
460 | ||
461 | While in Edebug, you can set a breakpoint with @kbd{b} and unset one | |
462 | with @kbd{u}. First move point to the Edebug stop point of your choice, | |
463 | then type @kbd{b} or @kbd{u} to set or unset a breakpoint there. | |
464 | Unsetting a breakpoint where none has been set has no effect. | |
465 | ||
a9f0a989 | 466 | Re-evaluating or reinstrumenting a definition forgets all its breakpoints. |
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467 | |
468 | A @dfn{conditional breakpoint} tests a condition each time the program | |
469 | gets there. Any errors that occur as a result of evaluating the | |
470 | condition are ignored, as if the result were @code{nil}. To set a | |
471 | conditional breakpoint, use @kbd{x}, and specify the condition | |
472 | expression in the minibuffer. Setting a conditional breakpoint at a | |
473 | stop point that has a previously established conditional breakpoint puts | |
474 | the previous condition expression in the minibuffer so you can edit it. | |
475 | ||
476 | You can make a conditional or unconditional breakpoint | |
969fe9b5 | 477 | @dfn{temporary} by using a prefix argument with the command to set the |
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478 | breakpoint. When a temporary breakpoint stops the program, it is |
479 | automatically unset. | |
480 | ||
481 | Edebug always stops or pauses at a breakpoint except when the Edebug | |
482 | mode is Go-nonstop. In that mode, it ignores breakpoints entirely. | |
483 | ||
484 | To find out where your breakpoints are, use the @kbd{B} command, which | |
87b2d5ff RS |
485 | moves point to the next breakpoint following point, within the same |
486 | function, or to the first breakpoint if there are no following | |
487 | breakpoints. This command does not continue execution---it just moves | |
488 | point in the buffer. | |
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489 | |
490 | @menu | |
491 | * Global Break Condition:: Breaking on an event. | |
492 | * Source Breakpoints:: Embedding breakpoints in source code. | |
493 | @end menu | |
494 | ||
495 | ||
496 | @node Global Break Condition | |
497 | @subsubsection Global Break Condition | |
498 | ||
499 | @cindex stopping on events | |
500 | @cindex global break condition | |
501 | A @dfn{global break condition} stops execution when a specified | |
502 | condition is satisfied, no matter where that may occur. Edebug | |
503 | evaluates the global break condition at every stop point. If it | |
504 | evaluates to a non-@code{nil} value, then execution stops or pauses | |
505 | depending on the execution mode, as if a breakpoint had been hit. If | |
506 | evaluating the condition gets an error, execution does not stop. | |
507 | ||
508 | @findex edebug-set-global-break-condition | |
9e2b495b RS |
509 | The condition expression is stored in |
510 | @code{edebug-global-break-condition}. You can specify a new expression | |
511 | using the @kbd{X} command (@code{edebug-set-global-break-condition}). | |
73804d4b RS |
512 | |
513 | The global break condition is the simplest way to find where in your | |
514 | code some event occurs, but it makes code run much more slowly. So you | |
515 | should reset the condition to @code{nil} when not using it. | |
516 | ||
517 | @node Source Breakpoints | |
518 | @subsubsection Source Breakpoints | |
519 | ||
520 | @findex edebug | |
521 | @cindex source breakpoints | |
522 | All breakpoints in a definition are forgotten each time you | |
523 | reinstrument it. To make a breakpoint that won't be forgotten, you can | |
524 | write a @dfn{source breakpoint}, which is simply a call to the function | |
525 | @code{edebug} in your source code. You can, of course, make such a call | |
526 | conditional. For example, in the @code{fac} function, insert the first | |
527 | line as shown below to stop when the argument reaches zero: | |
528 | ||
529 | @example | |
530 | (defun fac (n) | |
531 | (if (= n 0) (edebug)) | |
532 | (if (< 0 n) | |
533 | (* n (fac (1- n))) | |
534 | 1)) | |
535 | @end example | |
536 | ||
969fe9b5 | 537 | When the @code{fac} definition is instrumented and the function is |
73804d4b RS |
538 | called, the call to @code{edebug} acts as a breakpoint. Depending on |
539 | the execution mode, Edebug stops or pauses there. | |
540 | ||
969fe9b5 | 541 | If no instrumented code is being executed when @code{edebug} is called, |
73804d4b RS |
542 | that function calls @code{debug}. |
543 | @c This may not be a good idea anymore. | |
544 | ||
545 | @node Trapping Errors | |
546 | @subsection Trapping Errors | |
547 | ||
969fe9b5 RS |
548 | Emacs normally displays an error message when an error is signaled and |
549 | not handled with @code{condition-case}. While Edebug is active and | |
550 | executing instrumented code, it normally responds to all unhandled | |
551 | errors. You can customize this with the options @code{edebug-on-error} | |
552 | and @code{edebug-on-quit}; see @ref{Edebug Options}. | |
73804d4b | 553 | |
969fe9b5 | 554 | When Edebug responds to an error, it shows the last stop point |
73804d4b RS |
555 | encountered before the error. This may be the location of a call to a |
556 | function which was not instrumented, within which the error actually | |
557 | occurred. For an unbound variable error, the last known stop point | |
558 | might be quite distant from the offending variable reference. In that | |
559 | case you might want to display a full backtrace (@pxref{Edebug Misc}). | |
560 | ||
87b2d5ff | 561 | @c Edebug should be changed for the following: -- dan |
969fe9b5 | 562 | If you change @code{debug-on-error} or @code{debug-on-quit} while |
73804d4b RS |
563 | Edebug is active, these changes will be forgotten when Edebug becomes |
564 | inactive. Furthermore, during Edebug's recursive edit, these variables | |
565 | are bound to the values they had outside of Edebug. | |
566 | ||
73804d4b RS |
567 | @node Edebug Views |
568 | @subsection Edebug Views | |
569 | ||
969fe9b5 | 570 | These Edebug commands let you view aspects of the buffer and window |
a9f0a989 | 571 | status as they were before entry to Edebug. The outside window |
87b2d5ff RS |
572 | configuration is the collection of windows and contents that were in |
573 | effect outside of Edebug. | |
73804d4b RS |
574 | |
575 | @table @kbd | |
576 | @item v | |
87b2d5ff RS |
577 | Temporarily view the outside window configuration |
578 | (@code{edebug-view-outside}). | |
73804d4b RS |
579 | |
580 | @item p | |
581 | Temporarily display the outside current buffer with point at its outside | |
582 | position (@code{edebug-bounce-point}). With a prefix argument @var{n}, | |
583 | pause for @var{n} seconds instead. | |
584 | ||
585 | @item w | |
1911e6e5 RS |
586 | Move point back to the current stop point in the source code buffer |
587 | (@code{edebug-where}). | |
588 | ||
589 | If you use this command in a different window displaying the same | |
590 | buffer, that window will be used instead to display the current | |
591 | definition in the future. | |
73804d4b RS |
592 | |
593 | @item W | |
87b2d5ff RS |
594 | @c Its function is not simply to forget the saved configuration -- dan |
595 | Toggle whether Edebug saves and restores the outside window | |
596 | configuration (@code{edebug-toggle-save-windows}). | |
597 | ||
598 | With a prefix argument, @code{W} only toggles saving and restoring of | |
599 | the selected window. To specify a window that is not displaying the | |
600 | source code buffer, you must use @kbd{C-x X W} from the global keymap. | |
73804d4b RS |
601 | @end table |
602 | ||
969fe9b5 | 603 | You can view the outside window configuration with @kbd{v} or just |
73804d4b RS |
604 | bounce to the point in the current buffer with @kbd{p}, even if |
605 | it is not normally displayed. After moving point, you may wish to jump | |
606 | back to the stop point with @kbd{w} from a source code buffer. | |
607 | ||
969fe9b5 | 608 | Each time you use @kbd{W} to turn saving @emph{off}, Edebug forgets the |
87b2d5ff RS |
609 | saved outside window configuration---so that even if you turn saving |
610 | back @emph{on}, the current window configuration remains unchanged when | |
611 | you next exit Edebug (by continuing the program). However, the | |
612 | automatic redisplay of @samp{*edebug*} and @samp{*edebug-trace*} may | |
613 | conflict with the buffers you wish to see unless you have enough windows | |
614 | open. | |
73804d4b RS |
615 | |
616 | @node Edebug Eval | |
617 | @subsection Evaluation | |
618 | ||
969fe9b5 | 619 | While within Edebug, you can evaluate expressions ``as if'' Edebug were |
73804d4b RS |
620 | not running. Edebug tries to be invisible to the expression's |
621 | evaluation and printing. Evaluation of expressions that cause side | |
622 | effects will work as expected except for things that Edebug explicitly | |
623 | saves and restores. @xref{The Outside Context}, for details on this | |
624 | process. | |
625 | ||
626 | @table @kbd | |
627 | @item e @var{exp} @key{RET} | |
628 | Evaluate expression @var{exp} in the context outside of Edebug | |
629 | (@code{edebug-eval-expression}). That is, Edebug tries to minimize its | |
630 | interference with the evaluation. | |
631 | ||
bfe721d1 | 632 | @item M-: @var{exp} @key{RET} |
73804d4b RS |
633 | Evaluate expression @var{exp} in the context of Edebug itself. |
634 | ||
635 | @item C-x C-e | |
636 | Evaluate the expression before point, in the context outside of Edebug | |
637 | (@code{edebug-eval-last-sexp}). | |
638 | @end table | |
639 | ||
640 | @cindex lexical binding (Edebug) | |
969fe9b5 | 641 | Edebug supports evaluation of expressions containing references to |
73804d4b RS |
642 | lexically bound symbols created by the following constructs in |
643 | @file{cl.el} (version 2.03 or later): @code{lexical-let}, | |
644 | @code{macrolet}, and @code{symbol-macrolet}. | |
645 | ||
73804d4b RS |
646 | @node Eval List |
647 | @subsection Evaluation List Buffer | |
648 | ||
969fe9b5 | 649 | You can use the @dfn{evaluation list buffer}, called @samp{*edebug*}, to |
73804d4b RS |
650 | evaluate expressions interactively. You can also set up the |
651 | @dfn{evaluation list} of expressions to be evaluated automatically each | |
652 | time Edebug updates the display. | |
653 | ||
654 | @table @kbd | |
655 | @item E | |
656 | Switch to the evaluation list buffer @samp{*edebug*} | |
657 | (@code{edebug-visit-eval-list}). | |
658 | @end table | |
659 | ||
969fe9b5 | 660 | In the @samp{*edebug*} buffer you can use the commands of Lisp |
73804d4b RS |
661 | Interaction mode (@pxref{Lisp Interaction,,, emacs, The GNU Emacs |
662 | Manual}) as well as these special commands: | |
663 | ||
664 | @table @kbd | |
969fe9b5 | 665 | @item C-j |
73804d4b RS |
666 | Evaluate the expression before point, in the outside context, and insert |
667 | the value in the buffer (@code{edebug-eval-print-last-sexp}). | |
668 | ||
669 | @item C-x C-e | |
670 | Evaluate the expression before point, in the context outside of Edebug | |
671 | (@code{edebug-eval-last-sexp}). | |
672 | ||
673 | @item C-c C-u | |
87b2d5ff | 674 | Build a new evaluation list from the contents of the buffer |
73804d4b RS |
675 | (@code{edebug-update-eval-list}). |
676 | ||
677 | @item C-c C-d | |
678 | Delete the evaluation list group that point is in | |
679 | (@code{edebug-delete-eval-item}). | |
680 | ||
681 | @item C-c C-w | |
682 | Switch back to the source code buffer at the current stop point | |
683 | (@code{edebug-where}). | |
684 | @end table | |
685 | ||
969fe9b5 RS |
686 | You can evaluate expressions in the evaluation list window with |
687 | @kbd{C-j} or @kbd{C-x C-e}, just as you would in @samp{*scratch*}; | |
73804d4b RS |
688 | but they are evaluated in the context outside of Edebug. |
689 | ||
969fe9b5 | 690 | The expressions you enter interactively (and their results) are lost |
73804d4b RS |
691 | when you continue execution; but you can set up an @dfn{evaluation list} |
692 | consisting of expressions to be evaluated each time execution stops. | |
693 | ||
694 | @cindex evaluation list group | |
969fe9b5 | 695 | To do this, write one or more @dfn{evaluation list groups} in the |
73804d4b RS |
696 | evaluation list buffer. An evaluation list group consists of one or |
697 | more Lisp expressions. Groups are separated by comment lines. | |
698 | ||
969fe9b5 | 699 | The command @kbd{C-c C-u} (@code{edebug-update-eval-list}) rebuilds the |
73804d4b | 700 | evaluation list, scanning the buffer and using the first expression of |
87b2d5ff RS |
701 | each group. (The idea is that the second expression of the group is the |
702 | value previously computed and displayed.) | |
73804d4b | 703 | |
969fe9b5 | 704 | Each entry to Edebug redisplays the evaluation list by inserting each |
87b2d5ff RS |
705 | expression in the buffer, followed by its current value. It also |
706 | inserts comment lines so that each expression becomes its own group. | |
707 | Thus, if you type @kbd{C-c C-u} again without changing the buffer text, | |
708 | the evaluation list is effectively unchanged. | |
73804d4b | 709 | |
969fe9b5 | 710 | If an error occurs during an evaluation from the evaluation list, the |
73804d4b RS |
711 | error message is displayed in a string as if it were the result. |
712 | Therefore, expressions that use variables not currently valid do not | |
713 | interrupt your debugging. | |
714 | ||
969fe9b5 | 715 | Here is an example of what the evaluation list window looks like after |
73804d4b RS |
716 | several expressions have been added to it: |
717 | ||
718 | @smallexample | |
719 | (current-buffer) | |
720 | #<buffer *scratch*> | |
721 | ;--------------------------------------------------------------- | |
722 | (selected-window) | |
723 | #<window 16 on *scratch*> | |
724 | ;--------------------------------------------------------------- | |
725 | (point) | |
726 | 196 | |
727 | ;--------------------------------------------------------------- | |
728 | bad-var | |
729 | "Symbol's value as variable is void: bad-var" | |
730 | ;--------------------------------------------------------------- | |
731 | (recursion-depth) | |
732 | 0 | |
733 | ;--------------------------------------------------------------- | |
734 | this-command | |
735 | eval-last-sexp | |
736 | ;--------------------------------------------------------------- | |
737 | @end smallexample | |
738 | ||
739 | To delete a group, move point into it and type @kbd{C-c C-d}, or simply | |
740 | delete the text for the group and update the evaluation list with | |
741 | @kbd{C-c C-u}. To add a new expression to the evaluation list, insert | |
742 | the expression at a suitable place, and insert a new comment line. (You | |
743 | need not insert dashes in the comment line---its contents don't matter.) | |
744 | Then type @kbd{C-c C-u}. | |
745 | ||
746 | After selecting @samp{*edebug*}, you can return to the source code | |
747 | buffer with @kbd{C-c C-w}. The @samp{*edebug*} buffer is killed when | |
748 | you continue execution, and recreated next time it is needed. | |
749 | ||
73804d4b RS |
750 | @node Printing in Edebug |
751 | @subsection Printing in Edebug | |
752 | ||
753 | @cindex printing (Edebug) | |
754 | @cindex printing circular structures | |
755 | @pindex cust-print | |
756 | If an expression in your program produces a value containing circular | |
757 | list structure, you may get an error when Edebug attempts to print it. | |
758 | ||
73804d4b RS |
759 | One way to cope with circular structure is to set @code{print-length} |
760 | or @code{print-level} to truncate the printing. Edebug does this for | |
761 | you; it binds @code{print-length} and @code{print-level} to 50 if they | |
762 | were @code{nil}. (Actually, the variables @code{edebug-print-length} | |
763 | and @code{edebug-print-level} specify the values to use within Edebug.) | |
764 | @xref{Output Variables}. | |
765 | ||
969fe9b5 RS |
766 | @defopt edebug-print-length |
767 | If non-@code{nil}, bind @code{print-length} to this while printing | |
768 | results in Edebug. The default value is @code{50}. | |
969fe9b5 RS |
769 | @end defopt |
770 | ||
771 | @defopt edebug-print-level | |
772 | If non-@code{nil}, bind @code{print-level} to this while printing | |
773 | results in Edebug. The default value is @code{50}. | |
774 | @end defopt | |
775 | ||
73804d4b RS |
776 | You can also print circular structures and structures that share |
777 | elements more informatively by using the @file{cust-print} package. | |
778 | ||
779 | To load @file{cust-print} and activate custom printing only for | |
780 | Edebug, simply use the command @kbd{M-x edebug-install-custom-print}. | |
781 | To restore the standard print functions, use @kbd{M-x | |
782 | edebug-uninstall-custom-print}. | |
783 | ||
784 | Here is an example of code that creates a circular structure: | |
785 | ||
786 | @example | |
787 | (setq a '(x y)) | |
a9f0a989 | 788 | (setcar a a) |
73804d4b RS |
789 | @end example |
790 | ||
791 | @noindent | |
792 | Custom printing prints this as @samp{Result: #1=(#1# y)}. The | |
793 | @samp{#1=} notation labels the structure that follows it with the label | |
a9f0a989 | 794 | @samp{1}, and the @samp{#1#} notation references the previously labeled |
73804d4b RS |
795 | structure. This notation is used for any shared elements of lists or |
796 | vectors. | |
797 | ||
969fe9b5 RS |
798 | @defopt edebug-print-circle |
799 | If non-@code{nil}, bind @code{print-circle} to this while printing | |
800 | results in Edebug. The default value is @code{nil}. | |
801 | @end defopt | |
802 | ||
73804d4b RS |
803 | Other programs can also use custom printing; see @file{cust-print.el} |
804 | for details. | |
805 | ||
806 | @node Trace Buffer | |
807 | @subsection Trace Buffer | |
808 | @cindex trace buffer | |
809 | ||
87b2d5ff | 810 | Edebug can record an execution trace, storing it in a buffer named |
73804d4b RS |
811 | @samp{*edebug-trace*}. This is a log of function calls and returns, |
812 | showing the function names and their arguments and values. To enable | |
813 | trace recording, set @code{edebug-trace} to a non-@code{nil} value. | |
814 | ||
815 | Making a trace buffer is not the same thing as using trace execution | |
816 | mode (@pxref{Edebug Execution Modes}). | |
817 | ||
818 | When trace recording is enabled, each function entry and exit adds | |
819 | lines to the trace buffer. A function entry record looks like | |
820 | @samp{::::@{} followed by the function name and argument values. A | |
821 | function exit record looks like @samp{::::@}} followed by the function | |
822 | name and result of the function. | |
823 | ||
824 | The number of @samp{:}s in an entry shows its recursion depth. You | |
825 | can use the braces in the trace buffer to find the matching beginning or | |
826 | end of function calls. | |
827 | ||
828 | @findex edebug-print-trace-before | |
829 | @findex edebug-print-trace-after | |
830 | You can customize trace recording for function entry and exit by | |
831 | redefining the functions @code{edebug-print-trace-before} and | |
832 | @code{edebug-print-trace-after}. | |
833 | ||
834 | @defmac edebug-tracing string body@dots{} | |
835 | This macro requests additional trace information around the execution | |
836 | of the @var{body} forms. The argument @var{string} specifies text | |
837 | to put in the trace buffer. All the arguments are evaluated. | |
838 | @code{edebug-tracing} returns the value of the last form in @var{body}. | |
839 | @end defmac | |
840 | ||
841 | @defun edebug-trace format-string &rest format-args | |
842 | This function inserts text in the trace buffer. It computes the text | |
843 | with @code{(apply 'format @var{format-string} @var{format-args})}. | |
87b2d5ff | 844 | It also appends a newline to separate entries. |
73804d4b RS |
845 | @end defun |
846 | ||
1911e6e5 RS |
847 | @code{edebug-tracing} and @code{edebug-trace} insert lines in the |
848 | trace buffer whenever they are called, even if Edebug is not active. | |
849 | Adding text to the trace buffer also scrolls its window to show the last | |
850 | lines inserted. | |
73804d4b | 851 | |
73804d4b RS |
852 | @node Coverage Testing |
853 | @subsection Coverage Testing | |
854 | ||
855 | @cindex coverage testing | |
856 | @cindex frequency counts | |
857 | @cindex performance analysis | |
858 | Edebug provides rudimentary coverage testing and display of execution | |
1911e6e5 RS |
859 | frequency. |
860 | ||
861 | Coverage testing works by comparing the result of each expression with | |
862 | the previous result; each form in the program is considered ``covered'' | |
863 | if it has returned two different values since you began testing coverage | |
864 | in the current Emacs session. Thus, to do coverage testing on your | |
865 | program, execute it under various conditions and note whether it behaves | |
866 | correctly; Edebug will tell you when you have tried enough different | |
867 | conditions that each form has returned two different values. | |
868 | ||
869 | Coverage testing makes execution slower, so it is only done if | |
ebc6903b RS |
870 | @code{edebug-test-coverage} is non-@code{nil}. Frequency counting is |
871 | performed for all execution of an instrumented function, even if the | |
872 | execution mode is Go-nonstop, and regardless of whether coverage testing | |
873 | is enabled. | |
1911e6e5 RS |
874 | |
875 | Use @kbd{M-x edebug-display-freq-count} to display both the | |
a9f0a989 | 876 | coverage information and the frequency counts for a definition. |
73804d4b RS |
877 | |
878 | @deffn Command edebug-display-freq-count | |
879 | This command displays the frequency count data for each line of the | |
880 | current definition. | |
881 | ||
969fe9b5 RS |
882 | The frequency counts appear as comment lines after each line of code, |
883 | and you can undo all insertions with one @code{undo} command. The | |
884 | counts appear under the @samp{(} before an expression or the @samp{)} | |
a9f0a989 RS |
885 | after an expression, or on the last character of a variable. To |
886 | simplify the display, a count is not shown if it is equal to the | |
887 | count of an earlier expression on the same line. | |
73804d4b RS |
888 | |
889 | The character @samp{=} following the count for an expression says that | |
a9f0a989 | 890 | the expression has returned the same value each time it was evaluated. |
1911e6e5 | 891 | In other words, it is not yet ``covered'' for coverage testing purposes. |
73804d4b RS |
892 | |
893 | To clear the frequency count and coverage data for a definition, | |
a9f0a989 | 894 | simply reinstrument it with @code{eval-defun}. |
73804d4b RS |
895 | @end deffn |
896 | ||
897 | For example, after evaluating @code{(fac 5)} with a source | |
898 | breakpoint, and setting @code{edebug-test-coverage} to @code{t}, when | |
899 | the breakpoint is reached, the frequency data looks like this: | |
900 | ||
901 | @example | |
902 | (defun fac (n) | |
903 | (if (= n 0) (edebug)) | |
904 | ;#6 1 0 =5 | |
905 | (if (< 0 n) | |
906 | ;#5 = | |
907 | (* n (fac (1- n))) | |
908 | ;# 5 0 | |
909 | 1)) | |
910 | ;# 0 | |
911 | @end example | |
912 | ||
87b2d5ff RS |
913 | The comment lines show that @code{fac} was called 6 times. The |
914 | first @code{if} statement returned 5 times with the same result each | |
73804d4b | 915 | time; the same is true of the condition on the second @code{if}. |
87b2d5ff | 916 | The recursive call of @code{fac} did not return at all. |
73804d4b RS |
917 | |
918 | ||
919 | @node The Outside Context | |
920 | @subsection The Outside Context | |
921 | ||
922 | Edebug tries to be transparent to the program you are debugging, but it | |
923 | does not succeed completely. Edebug also tries to be transparent when | |
924 | you evaluate expressions with @kbd{e} or with the evaluation list | |
925 | buffer, by temporarily restoring the outside context. This section | |
926 | explains precisely what context Edebug restores, and how Edebug fails to | |
927 | be completely transparent. | |
928 | ||
73804d4b RS |
929 | @menu |
930 | * Checking Whether to Stop:: When Edebug decides what to do. | |
931 | * Edebug Display Update:: When Edebug updates the display. | |
932 | * Edebug Recursive Edit:: When Edebug stops execution. | |
933 | @end menu | |
934 | ||
935 | @node Checking Whether to Stop | |
936 | @subsubsection Checking Whether to Stop | |
937 | ||
87b2d5ff RS |
938 | Whenever Edebug is entered, it needs to save and restore certain data |
939 | before even deciding whether to make trace information or stop the | |
940 | program. | |
73804d4b RS |
941 | |
942 | @itemize @bullet | |
943 | @item | |
944 | @code{max-lisp-eval-depth} and @code{max-specpdl-size} are both | |
a9f0a989 RS |
945 | incremented once to reduce Edebug's impact on the stack. You could, |
946 | however, still run out of stack space when using Edebug. | |
73804d4b RS |
947 | |
948 | @item | |
949 | The state of keyboard macro execution is saved and restored. While | |
950 | Edebug is active, @code{executing-macro} is bound to | |
951 | @code{edebug-continue-kbd-macro}. | |
952 | ||
953 | @end itemize | |
954 | ||
955 | ||
956 | @node Edebug Display Update | |
957 | @subsubsection Edebug Display Update | |
958 | ||
87b2d5ff RS |
959 | @c This paragraph is not filled, because LaLiberte's conversion script |
960 | @c needs an xref to be on just one line. | |
73804d4b | 961 | When Edebug needs to display something (e.g., in trace mode), it saves |
87b2d5ff RS |
962 | the current window configuration from ``outside'' Edebug |
963 | (@pxref{Window Configurations}). When you exit Edebug (by continuing | |
964 | the program), it restores the previous window configuration. | |
73804d4b RS |
965 | |
966 | Emacs redisplays only when it pauses. Usually, when you continue | |
967 | execution, the program comes back into Edebug at a breakpoint or after | |
968 | stepping without pausing or reading input in between. In such cases, | |
969 | Emacs never gets a chance to redisplay the ``outside'' configuration. | |
970 | What you see is the same window configuration as the last time Edebug | |
971 | was active, with no interruption. | |
972 | ||
973 | Entry to Edebug for displaying something also saves and restores the | |
974 | following data, but some of these are deliberately not restored if an | |
975 | error or quit signal occurs. | |
976 | ||
977 | @itemize @bullet | |
978 | @item | |
979 | @cindex current buffer point and mark (Edebug) | |
980 | Which buffer is current, and the positions of point and the mark in the | |
981 | current buffer, are saved and restored. | |
982 | ||
983 | @item | |
984 | @cindex window configuration (Edebug) | |
985 | The outside window configuration is saved and restored if | |
986 | @code{edebug-save-windows} is non-@code{nil} (@pxref{Edebug Display Update}). | |
987 | ||
988 | The window configuration is not restored on error or quit, but the | |
989 | outside selected window @emph{is} reselected even on error or quit in | |
990 | case a @code{save-excursion} is active. If the value of | |
991 | @code{edebug-save-windows} is a list, only the listed windows are saved | |
992 | and restored. | |
993 | ||
994 | The window start and horizontal scrolling of the source code buffer are | |
995 | not restored, however, so that the display remains coherent within Edebug. | |
996 | ||
997 | @item | |
73804d4b RS |
998 | The value of point in each displayed buffer is saved and restored if |
999 | @code{edebug-save-displayed-buffer-points} is non-@code{nil}. | |
1000 | ||
1001 | @item | |
1002 | The variables @code{overlay-arrow-position} and | |
1003 | @code{overlay-arrow-string} are saved and restored. So you can safely | |
1004 | invoke Edebug from the recursive edit elsewhere in the same buffer. | |
1005 | ||
1006 | @item | |
1007 | @code{cursor-in-echo-area} is locally bound to @code{nil} so that | |
1008 | the cursor shows up in the window. | |
1009 | @end itemize | |
1010 | ||
1011 | @node Edebug Recursive Edit | |
1012 | @subsubsection Edebug Recursive Edit | |
1013 | ||
1014 | When Edebug is entered and actually reads commands from the user, it | |
1015 | saves (and later restores) these additional data: | |
1016 | ||
1017 | @itemize @bullet | |
1018 | @item | |
1019 | The current match data. @xref{Match Data}. | |
1020 | ||
1021 | @item | |
1022 | @code{last-command}, @code{this-command}, @code{last-command-char}, | |
1023 | @code{last-input-char}, @code{last-input-event}, | |
1024 | @code{last-command-event}, @code{last-event-frame}, | |
1025 | @code{last-nonmenu-event}, and @code{track-mouse}. Commands used within | |
1026 | Edebug do not affect these variables outside of Edebug. | |
1027 | ||
1028 | The key sequence returned by @code{this-command-keys} is changed by | |
1029 | executing commands within Edebug and there is no way to reset | |
1030 | the key sequence from Lisp. | |
1031 | ||
87b2d5ff RS |
1032 | Edebug cannot save and restore the value of |
1033 | @code{unread-command-events}. Entering Edebug while this variable has a | |
1034 | nontrivial value can interfere with execution of the program you are | |
1035 | debugging. | |
1036 | ||
73804d4b RS |
1037 | @item |
1038 | Complex commands executed while in Edebug are added to the variable | |
1039 | @code{command-history}. In rare cases this can alter execution. | |
1040 | ||
1041 | @item | |
1042 | Within Edebug, the recursion depth appears one deeper than the recursion | |
1043 | depth outside Edebug. This is not true of the automatically updated | |
1044 | evaluation list window. | |
1045 | ||
1046 | @item | |
1047 | @code{standard-output} and @code{standard-input} are bound to @code{nil} | |
1048 | by the @code{recursive-edit}, but Edebug temporarily restores them during | |
1049 | evaluations. | |
1050 | ||
1051 | @item | |
1052 | The state of keyboard macro definition is saved and restored. While | |
1053 | Edebug is active, @code{defining-kbd-macro} is bound to | |
1054 | @code{edebug-continue-kbd-macro}. | |
1055 | @end itemize | |
1056 | ||
1057 | @node Instrumenting Macro Calls | |
1058 | @subsection Instrumenting Macro Calls | |
1059 | ||
969fe9b5 RS |
1060 | When Edebug instruments an expression that calls a Lisp macro, it needs |
1061 | additional information about the macro to do the job properly. This is | |
1062 | because there is no a-priori way to tell which subexpressions of the | |
1063 | macro call are forms to be evaluated. (Evaluation may occur explicitly | |
1064 | in the macro body, or when the resulting expansion is evaluated, or any | |
1065 | time later.) | |
1066 | ||
1067 | Therefore, you must define an Edebug specification for each macro that | |
1068 | Edebug will encounter, to explain the format of calls to that macro. To | |
1069 | do this, use @code{def-edebug-spec}. | |
73804d4b RS |
1070 | |
1071 | @deffn Macro def-edebug-spec macro specification | |
1072 | Specify which expressions of a call to macro @var{macro} are forms to be | |
1073 | evaluated. For simple macros, the @var{specification} often looks very | |
1074 | similar to the formal argument list of the macro definition, but | |
1075 | specifications are much more general than macro arguments. | |
1076 | ||
969fe9b5 | 1077 | The @var{macro} argument can actually be any symbol, not just a macro |
73804d4b RS |
1078 | name. |
1079 | @end deffn | |
1080 | ||
1081 | Here is a simple example that defines the specification for the | |
1911e6e5 | 1082 | @code{for} example macro (@pxref{Argument Evaluation}), followed by an |
a9f0a989 | 1083 | alternative, equivalent specification. |
73804d4b RS |
1084 | |
1085 | @example | |
1086 | (def-edebug-spec for | |
1087 | (symbolp "from" form "to" form "do" &rest form)) | |
1088 | ||
1089 | (def-edebug-spec for | |
1090 | (symbolp ['from form] ['to form] ['do body])) | |
1091 | @end example | |
1092 | ||
1093 | Here is a table of the possibilities for @var{specification} and how each | |
1094 | directs processing of arguments. | |
1095 | ||
ec221d13 | 1096 | @table @asis |
73804d4b RS |
1097 | @item @code{t} |
1098 | All arguments are instrumented for evaluation. | |
1099 | ||
1100 | @item @code{0} | |
1101 | None of the arguments is instrumented. | |
1102 | ||
1103 | @item a symbol | |
1104 | The symbol must have an Edebug specification which is used instead. | |
1105 | This indirection is repeated until another kind of specification is | |
a9f0a989 | 1106 | found. This allows you to inherit the specification from another macro. |
73804d4b RS |
1107 | |
1108 | @item a list | |
1109 | The elements of the list describe the types of the arguments of a | |
1110 | calling form. The possible elements of a specification list are | |
1111 | described in the following sections. | |
1112 | @end table | |
1113 | ||
1114 | @menu | |
1115 | * Specification List:: How to specify complex patterns of evaluation. | |
1116 | * Backtracking:: What Edebug does when matching fails. | |
73804d4b RS |
1117 | * Specification Examples:: To help understand specifications. |
1118 | @end menu | |
1119 | ||
1120 | ||
1121 | @node Specification List | |
1122 | @subsubsection Specification List | |
1123 | ||
1124 | @cindex Edebug specification list | |
1125 | A @dfn{specification list} is required for an Edebug specification if | |
1126 | some arguments of a macro call are evaluated while others are not. Some | |
1127 | elements in a specification list match one or more arguments, but others | |
1128 | modify the processing of all following elements. The latter, called | |
1129 | @dfn{specification keywords}, are symbols beginning with @samp{&} (such | |
1130 | as @code{&optional}). | |
1131 | ||
1132 | A specification list may contain sublists which match arguments that are | |
1133 | themselves lists, or it may contain vectors used for grouping. Sublists | |
1134 | and groups thus subdivide the specification list into a hierarchy of | |
969fe9b5 | 1135 | levels. Specification keywords apply only to the remainder of the |
73804d4b RS |
1136 | sublist or group they are contained in. |
1137 | ||
1138 | When a specification list involves alternatives or repetition, matching | |
1139 | it against an actual macro call may require backtracking. | |
1140 | @xref{Backtracking}, for more details. | |
1141 | ||
1142 | Edebug specifications provide the power of regular expression matching, | |
1143 | plus some context-free grammar constructs: the matching of sublists with | |
1144 | balanced parentheses, recursive processing of forms, and recursion via | |
1145 | indirect specifications. | |
1146 | ||
1147 | Here's a table of the possible elements of a specification list, with | |
1148 | their meanings: | |
1149 | ||
1150 | @table @code | |
1151 | @item sexp | |
1911e6e5 | 1152 | A single unevaluated Lisp object, which is not instrumented. |
a9f0a989 | 1153 | @c an "expression" is not necessarily intended for evaluation. |
73804d4b RS |
1154 | |
1155 | @item form | |
1156 | A single evaluated expression, which is instrumented. | |
1157 | ||
1158 | @item place | |
1159 | @findex edebug-unwrap | |
1160 | A place to store a value, as in the Common Lisp @code{setf} construct. | |
1161 | ||
1162 | @item body | |
1163 | Short for @code{&rest form}. See @code{&rest} below. | |
1164 | ||
1165 | @item function-form | |
1166 | A function form: either a quoted function symbol, a quoted lambda | |
1167 | expression, or a form (that should evaluate to a function symbol or | |
1168 | lambda expression). This is useful when an argument that's a lambda | |
1169 | expression might be quoted with @code{quote} rather than | |
1170 | @code{function}, since it instruments the body of the lambda expression | |
1171 | either way. | |
1172 | ||
1173 | @item lambda-expr | |
1174 | A lambda expression with no quoting. | |
1175 | ||
1176 | @item &optional | |
1177 | @kindex &optional @r{(Edebug)} | |
1178 | All following elements in the specification list are optional; as soon | |
1179 | as one does not match, Edebug stops matching at this level. | |
1180 | ||
1181 | To make just a few elements optional followed by non-optional elements, | |
1182 | use @code{[&optional @var{specs}@dots{}]}. To specify that several | |
1183 | elements must all match or none, use @code{&optional | |
1184 | [@var{specs}@dots{}]}. See the @code{defun} example below. | |
1185 | ||
1186 | @item &rest | |
1187 | @kindex &rest @r{(Edebug)} | |
1188 | All following elements in the specification list are repeated zero or | |
ebc6903b RS |
1189 | more times. In the last repetition, however, it is not a problem if the |
1190 | expression runs out before matching all of the elements of the | |
1191 | specification list. | |
73804d4b RS |
1192 | |
1193 | To repeat only a few elements, use @code{[&rest @var{specs}@dots{}]}. | |
1194 | To specify several elements that must all match on every repetition, use | |
1195 | @code{&rest [@var{specs}@dots{}]}. | |
1196 | ||
1197 | @item &or | |
1198 | @kindex &or @r{(Edebug)} | |
1199 | Each of the following elements in the specification list is an | |
1200 | alternative. One of the alternatives must match, or the @code{&or} | |
1201 | specification fails. | |
1202 | ||
1203 | Each list element following @code{&or} is a single alternative. To | |
1204 | group two or more list elements as a single alternative, enclose them in | |
1205 | @code{[@dots{}]}. | |
1206 | ||
1207 | @item ¬ | |
1208 | @kindex ¬ @r{(Edebug)} | |
1209 | Each of the following elements is matched as alternatives as if by using | |
1210 | @code{&or}, but if any of them match, the specification fails. If none | |
1211 | of them match, nothing is matched, but the @code{¬} specification | |
1212 | succeeds. | |
1213 | ||
1214 | @item &define | |
1215 | @kindex &define @r{(Edebug)} | |
1216 | Indicates that the specification is for a defining form. The defining | |
a9f0a989 | 1217 | form itself is not instrumented (that is, Edebug does not stop before and |
73804d4b RS |
1218 | after the defining form), but forms inside it typically will be |
1219 | instrumented. The @code{&define} keyword should be the first element in | |
1220 | a list specification. | |
1221 | ||
1222 | @item nil | |
1223 | This is successful when there are no more arguments to match at the | |
1224 | current argument list level; otherwise it fails. See sublist | |
1225 | specifications and the backquote example below. | |
1226 | ||
1227 | @item gate | |
1228 | @cindex preventing backtracking | |
1229 | No argument is matched but backtracking through the gate is disabled | |
1230 | while matching the remainder of the specifications at this level. This | |
1231 | is primarily used to generate more specific syntax error messages. See | |
1232 | @ref{Backtracking}, for more details. Also see the @code{let} example | |
1233 | below. | |
1234 | ||
1235 | @item @var{other-symbol} | |
1236 | @cindex indirect specifications | |
1237 | Any other symbol in a specification list may be a predicate or an | |
1238 | indirect specification. | |
1239 | ||
1240 | If the symbol has an Edebug specification, this @dfn{indirect | |
1241 | specification} should be either a list specification that is used in | |
1242 | place of the symbol, or a function that is called to process the | |
1243 | arguments. The specification may be defined with @code{def-edebug-spec} | |
1244 | just as for macros. See the @code{defun} example below. | |
1245 | ||
1246 | Otherwise, the symbol should be a predicate. The predicate is called | |
1247 | with the argument and the specification fails if the predicate returns | |
1248 | @code{nil}. In either case, that argument is not instrumented. | |
1249 | ||
73804d4b RS |
1250 | Some suitable predicates include @code{symbolp}, @code{integerp}, |
1251 | @code{stringp}, @code{vectorp}, and @code{atom}. | |
73804d4b RS |
1252 | |
1253 | @item [@var{elements}@dots{}] | |
1254 | @cindex [@dots{}] (Edebug) | |
1255 | A vector of elements groups the elements into a single @dfn{group | |
1256 | specification}. Its meaning has nothing to do with vectors. | |
1257 | ||
1258 | @item "@var{string}" | |
1259 | The argument should be a symbol named @var{string}. This specification | |
1260 | is equivalent to the quoted symbol, @code{'@var{symbol}}, where the name | |
1261 | of @var{symbol} is the @var{string}, but the string form is preferred. | |
1262 | ||
73804d4b RS |
1263 | @item (vector @var{elements}@dots{}) |
1264 | The argument should be a vector whose elements must match the | |
1265 | @var{elements} in the specification. See the backquote example below. | |
1266 | ||
1267 | @item (@var{elements}@dots{}) | |
1268 | Any other list is a @dfn{sublist specification} and the argument must be | |
1269 | a list whose elements match the specification @var{elements}. | |
1270 | ||
1271 | @cindex dotted lists (Edebug) | |
1272 | A sublist specification may be a dotted list and the corresponding list | |
1273 | argument may then be a dotted list. Alternatively, the last @sc{cdr} of a | |
1274 | dotted list specification may be another sublist specification (via a | |
a9f0a989 | 1275 | grouping or an indirect specification, e.g., @code{(spec . [(more |
73804d4b RS |
1276 | specs@dots{})])}) whose elements match the non-dotted list arguments. |
1277 | This is useful in recursive specifications such as in the backquote | |
1278 | example below. Also see the description of a @code{nil} specification | |
1279 | above for terminating such recursion. | |
1280 | ||
87b2d5ff RS |
1281 | Note that a sublist specification written as @code{(specs . nil)} |
1282 | is equivalent to @code{(specs)}, and @code{(specs . | |
1283 | (sublist-elements@dots{}))} is equivalent to @code{(specs | |
73804d4b RS |
1284 | sublist-elements@dots{})}. |
1285 | @end table | |
1286 | ||
1287 | @c Need to document extensions with &symbol and :symbol | |
1288 | ||
969fe9b5 | 1289 | Here is a list of additional specifications that may appear only after |
73804d4b RS |
1290 | @code{&define}. See the @code{defun} example below. |
1291 | ||
1292 | @table @code | |
1293 | @item name | |
1294 | The argument, a symbol, is the name of the defining form. | |
1295 | ||
1296 | A defining form is not required to have a name field; and it may have | |
1297 | multiple name fields. | |
1298 | ||
1299 | @item :name | |
1300 | This construct does not actually match an argument. The element | |
1301 | following @code{:name} should be a symbol; it is used as an additional | |
1302 | name component for the definition. You can use this to add a unique, | |
1303 | static component to the name of the definition. It may be used more | |
1304 | than once. | |
1305 | ||
1306 | @item arg | |
1307 | The argument, a symbol, is the name of an argument of the defining form. | |
a9f0a989 | 1308 | However, lambda-list keywords (symbols starting with @samp{&}) |
87b2d5ff | 1309 | are not allowed. |
73804d4b RS |
1310 | |
1311 | @item lambda-list | |
1312 | @cindex lambda-list (Edebug) | |
1313 | This matches a lambda list---the argument list of a lambda expression. | |
73804d4b RS |
1314 | |
1315 | @item def-body | |
1316 | The argument is the body of code in a definition. This is like | |
1317 | @code{body}, described above, but a definition body must be instrumented | |
1318 | with a different Edebug call that looks up information associated with | |
1319 | the definition. Use @code{def-body} for the highest level list of forms | |
1320 | within the definition. | |
1321 | ||
1322 | @item def-form | |
1323 | The argument is a single, highest-level form in a definition. This is | |
1324 | like @code{def-body}, except use this to match a single form rather than | |
1325 | a list of forms. As a special case, @code{def-form} also means that | |
1326 | tracing information is not output when the form is executed. See the | |
1327 | @code{interactive} example below. | |
1328 | @end table | |
1329 | ||
1330 | @node Backtracking | |
969fe9b5 | 1331 | @subsubsection Backtracking in Specifications |
73804d4b RS |
1332 | |
1333 | @cindex backtracking | |
1334 | @cindex syntax error (Edebug) | |
1335 | If a specification fails to match at some point, this does not | |
1336 | necessarily mean a syntax error will be signaled; instead, | |
1337 | @dfn{backtracking} will take place until all alternatives have been | |
1338 | exhausted. Eventually every element of the argument list must be | |
1339 | matched by some element in the specification, and every required element | |
1340 | in the specification must match some argument. | |
a9f0a989 RS |
1341 | |
1342 | When a syntax error is detected, it might not be reported until much | |
1343 | later after higher-level alternatives have been exhausted, and with the | |
1344 | point positioned further from the real error. But if backtracking is | |
1345 | disabled when an error occurs, it can be reported immediately. Note | |
1346 | that backtracking is also reenabled automatically in several situations; | |
1347 | it is reenabled when a new alternative is established by | |
1348 | @code{&optional}, @code{&rest}, or @code{&or}, or at the start of | |
1349 | processing a sublist, group, or indirect specification. The effect of | |
1350 | enabling or disabling backtracking is limited to the remainder of the | |
1351 | level currently being processed and lower levels. | |
1352 | ||
1353 | Backtracking is disabled while matching any of the | |
1354 | form specifications (that is, @code{form}, @code{body}, @code{def-form}, and | |
73804d4b RS |
1355 | @code{def-body}). These specifications will match any form so any error |
1356 | must be in the form itself rather than at a higher level. | |
1357 | ||
a9f0a989 | 1358 | Backtracking is also disabled after successfully matching a quoted |
73804d4b | 1359 | symbol or string specification, since this usually indicates a |
a9f0a989 | 1360 | recognized construct. But if you have a set of alternative constructs that |
73804d4b RS |
1361 | all begin with the same symbol, you can usually work around this |
1362 | constraint by factoring the symbol out of the alternatives, e.g., | |
1363 | @code{["foo" &or [first case] [second case] ...]}. | |
1364 | ||
a9f0a989 RS |
1365 | Most needs are satisfied by these two ways that bactracking is |
1366 | automatically disabled, but occasionally it is useful to explicitly | |
1367 | disable backtracking by using the @code{gate} specification. This is | |
1368 | useful when you know that no higher alternatives could apply. See the | |
1369 | example of the @code{let} specification. | |
73804d4b | 1370 | |
73804d4b RS |
1371 | @node Specification Examples |
1372 | @subsubsection Specification Examples | |
1373 | ||
1374 | It may be easier to understand Edebug specifications by studying | |
1375 | the examples provided here. | |
1376 | ||
1377 | A @code{let} special form has a sequence of bindings and a body. Each | |
1378 | of the bindings is either a symbol or a sublist with a symbol and | |
a9f0a989 | 1379 | optional expression. In the specification below, notice the @code{gate} |
73804d4b RS |
1380 | inside of the sublist to prevent backtracking once a sublist is found. |
1381 | ||
1382 | @example | |
1383 | (def-edebug-spec let | |
1384 | ((&rest | |
1385 | &or symbolp (gate symbolp &optional form)) | |
1386 | body)) | |
1387 | @end example | |
1388 | ||
1389 | Edebug uses the following specifications for @code{defun} and | |
1390 | @code{defmacro} and the associated argument list and @code{interactive} | |
1391 | specifications. It is necessary to handle interactive forms specially | |
1392 | since an expression argument it is actually evaluated outside of the | |
1393 | function body. | |
1394 | ||
87b2d5ff RS |
1395 | @smallexample |
1396 | (def-edebug-spec defmacro defun) ; @r{Indirect ref to @code{defun} spec.} | |
73804d4b RS |
1397 | (def-edebug-spec defun |
1398 | (&define name lambda-list | |
87b2d5ff | 1399 | [&optional stringp] ; @r{Match the doc string, if present.} |
73804d4b RS |
1400 | [&optional ("interactive" interactive)] |
1401 | def-body)) | |
1402 | ||
1403 | (def-edebug-spec lambda-list | |
1404 | (([&rest arg] | |
1405 | [&optional ["&optional" arg &rest arg]] | |
1406 | &optional ["&rest" arg] | |
1407 | ))) | |
1408 | ||
1409 | (def-edebug-spec interactive | |
1410 | (&optional &or stringp def-form)) ; @r{Notice: @code{def-form}} | |
87b2d5ff | 1411 | @end smallexample |
73804d4b RS |
1412 | |
1413 | The specification for backquote below illustrates how to match | |
1414 | dotted lists and use @code{nil} to terminate recursion. It also | |
1415 | illustrates how components of a vector may be matched. (The actual | |
1416 | specification defined by Edebug does not support dotted lists because | |
1417 | doing so causes very deep recursion that could fail.) | |
1418 | ||
87b2d5ff RS |
1419 | @smallexample |
1420 | (def-edebug-spec ` (backquote-form)) ; @r{Alias just for clarity.} | |
73804d4b RS |
1421 | |
1422 | (def-edebug-spec backquote-form | |
1423 | (&or ([&or "," ",@@"] &or ("quote" backquote-form) form) | |
1424 | (backquote-form . [&or nil backquote-form]) | |
1425 | (vector &rest backquote-form) | |
1426 | sexp)) | |
87b2d5ff | 1427 | @end smallexample |
73804d4b RS |
1428 | |
1429 | ||
1430 | @node Edebug Options | |
1431 | @subsection Edebug Options | |
1432 | ||
1433 | These options affect the behavior of Edebug: | |
1434 | ||
1435 | @defopt edebug-setup-hook | |
1436 | Functions to call before Edebug is used. Each time it is set to a new | |
1437 | value, Edebug will call those functions once and then | |
1438 | @code{edebug-setup-hook} is reset to @code{nil}. You could use this to | |
1439 | load up Edebug specifications associated with a package you are using | |
1440 | but only when you also use Edebug. | |
1441 | @xref{Instrumenting}. | |
1442 | @end defopt | |
1443 | ||
1444 | @defopt edebug-all-defs | |
1445 | If this is non-@code{nil}, normal evaluation of defining forms such as | |
1446 | @code{defun} and @code{defmacro} instruments them for Edebug. This | |
87b2d5ff RS |
1447 | applies to @code{eval-defun}, @code{eval-region}, @code{eval-buffer}, |
1448 | and @code{eval-current-buffer}. | |
1449 | ||
1450 | Use the command @kbd{M-x edebug-all-defs} to toggle the value of this | |
1451 | option. @xref{Instrumenting}. | |
73804d4b RS |
1452 | @end defopt |
1453 | ||
1454 | @defopt edebug-all-forms | |
87b2d5ff RS |
1455 | If this is non-@code{nil}, the commands @code{eval-defun}, |
1456 | @code{eval-region}, @code{eval-buffer}, and @code{eval-current-buffer} | |
1457 | instrument all forms, even those that don't define anything. | |
1458 | This doesn't apply to loading or evaluations in the minibuffer. | |
73804d4b RS |
1459 | |
1460 | Use the command @kbd{M-x edebug-all-forms} to toggle the value of this | |
87b2d5ff | 1461 | option. @xref{Instrumenting}. |
73804d4b RS |
1462 | @end defopt |
1463 | ||
1464 | @defopt edebug-save-windows | |
1465 | If this is non-@code{nil}, Edebug saves and restores the window | |
1466 | configuration. That takes some time, so if your program does not care | |
1467 | what happens to the window configurations, it is better to set this | |
1468 | variable to @code{nil}. | |
1469 | ||
1470 | If the value is a list, only the listed windows are saved and | |
1471 | restored. | |
1472 | ||
1473 | You can use the @kbd{W} command in Edebug to change this variable | |
1474 | interactively. @xref{Edebug Display Update}. | |
1475 | @end defopt | |
1476 | ||
1477 | @defopt edebug-save-displayed-buffer-points | |
87b2d5ff RS |
1478 | If this is non-@code{nil}, Edebug saves and restores point in all |
1479 | displayed buffers. | |
73804d4b RS |
1480 | |
1481 | Saving and restoring point in other buffers is necessary if you are | |
1482 | debugging code that changes the point of a buffer which is displayed in | |
1483 | a non-selected window. If Edebug or the user then selects the window, | |
87b2d5ff | 1484 | point in that buffer will move to the window's value of point. |
73804d4b RS |
1485 | |
1486 | Saving and restoring point in all buffers is expensive, since it | |
1487 | requires selecting each window twice, so enable this only if you need | |
1488 | it. @xref{Edebug Display Update}. | |
1489 | @end defopt | |
1490 | ||
1491 | @defopt edebug-initial-mode | |
1492 | If this variable is non-@code{nil}, it specifies the initial execution | |
1493 | mode for Edebug when it is first activated. Possible values are | |
1494 | @code{step}, @code{next}, @code{go}, @code{Go-nonstop}, @code{trace}, | |
1495 | @code{Trace-fast}, @code{continue}, and @code{Continue-fast}. | |
1496 | ||
1497 | The default value is @code{step}. | |
1498 | @xref{Edebug Execution Modes}. | |
1499 | @end defopt | |
1500 | ||
1501 | @defopt edebug-trace | |
73804d4b RS |
1502 | Non-@code{nil} means display a trace of function entry and exit. |
1503 | Tracing output is displayed in a buffer named @samp{*edebug-trace*}, one | |
1504 | function entry or exit per line, indented by the recursion level. | |
1505 | ||
1506 | The default value is @code{nil}. | |
1507 | ||
a9f0a989 | 1508 | Also see @code{edebug-tracing}, in @ref{Trace Buffer}. |
73804d4b RS |
1509 | @end defopt |
1510 | ||
1511 | @defopt edebug-test-coverage | |
1512 | If non-@code{nil}, Edebug tests coverage of all expressions debugged. | |
73804d4b RS |
1513 | @xref{Coverage Testing}. |
1514 | @end defopt | |
1515 | ||
1516 | @defopt edebug-continue-kbd-macro | |
1517 | If non-@code{nil}, continue defining or executing any keyboard macro | |
1518 | that is executing outside of Edebug. Use this with caution since it is not | |
1519 | debugged. | |
1520 | @xref{Edebug Execution Modes}. | |
1521 | @end defopt | |
1522 | ||
73804d4b RS |
1523 | @defopt edebug-on-error |
1524 | Edebug binds @code{debug-on-error} to this value, if | |
1525 | @code{debug-on-error} was previously @code{nil}. @xref{Trapping | |
1526 | Errors}. | |
1527 | @end defopt | |
1528 | ||
1529 | @defopt edebug-on-quit | |
1530 | Edebug binds @code{debug-on-quit} to this value, if | |
1531 | @code{debug-on-quit} was previously @code{nil}. @xref{Trapping | |
1532 | Errors}. | |
1533 | @end defopt | |
1534 | ||
1535 | If you change the values of @code{edebug-on-error} or | |
1536 | @code{edebug-on-quit} while Edebug is active, their values won't be used | |
87b2d5ff RS |
1537 | until the @emph{next} time Edebug is invoked via a new command. |
1538 | @c Not necessarily a deeper command level. | |
1539 | @c A new command is not precisely true, but that is close enough -- dan | |
73804d4b RS |
1540 | |
1541 | @defopt edebug-global-break-condition | |
1542 | If non-@code{nil}, an expression to test for at every stop point. | |
1543 | If the result is non-nil, then break. Errors are ignored. | |
1544 | @xref{Global Break Condition}. | |
1545 | @end defopt |