-
Notifications
You must be signed in to change notification settings - Fork 0
/
expeditor.html
828 lines (598 loc) · 29 KB
/
expeditor.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd"><!-- DO NOT EDIT THIS FILE-->
<!-- Edit the .tex version instead-->
<html>
<head>
<title>Expression Editor</title>
<link href="csug.css" rel="stylesheet" type="text/css">
</head>
<body>
<a name="g128"></a>
<a name="./expeditor:h0"></a>
<h1>Chapter 14. Expression Editor<a name="CHPTEXPEDITOR"></a></h1>
<p>
When the expression editor (expeditor) is enabled as described in
Section <a href="./use.html#g7">2.2</a>, it allows the user to edit expressions
entered into the system and move backwards and forwards through
a history of entered expressions.
This chapter describes a set of parameters that may be used to
control various aspects of the expression editor's behavior
(Section <a href="./expeditor.html#g129">14.1</a>),
a procedure for binding key sequences to editing commands
(Section <a href="./expeditor.html#g130">14.2</a>),
the built-in editing commands
(Section <a href="./expeditor.html#g131">14.3</a>), and mechanisms for creating new
editing commands (Section <a href="./expeditor.html#g132">14.4</a>).
<p>
These mechanisms are available through the <tt>expression-editor</tt> module.
<p>
<a name="./expeditor:s0"></a><span class=formdef><b>module</b>: <tt>expression-editor</tt></span>
<br>
<b>libraries: </b><tt>(chezscheme)</tt>
<p>The <tt>expression-editor</tt> module exports a set of bindings for
parameters and other procedures that can be used to modify how the
expression editor interacts with the user, including the particular keys
used to invoke the various editing commands.
<p>
<p>Basic use of the expression editor is described in Section <a href="./use.html#g7">2.2</a>.
<p>
<h3><a name="g129"></a><a name="./expeditor:h1"></a>Section 14.1. Expression Editor Parameters<a name="SECTEXPEDITORPARAMS"></a></h3>
<p>
<a name="./expeditor:s1"></a><span class=formdef><b>global parameter</b>: <tt>ee-auto-indent</tt></span>
<p>
<p>The value of <tt>ee-auto-indent</tt> is a boolean value that determines
whether the expression editor indents expressions as they are entered.
Its default value is <tt>#t</tt>.
<p>
<a name="./expeditor:s2"></a><span class=formdef><b>global parameter</b>: <tt>ee-standard-indent</tt></span>
<p>
<p>The value of <tt>ee-standard-indent</tt> is a nonnegative fixnum
value that determines the amount (in single spaces) by which each
expression is indented relative to the enclosing expression, if
not aligned otherwise by one of the indenter's other heuristics,
when <tt>ee-auto-indent</tt> is true or when one of the indentation
commands is invoked explicitly.
It's default value is <tt>2</tt>.
<p>
<a name="./expeditor:s3"></a><span class=formdef><b>global parameter</b>: <tt>ee-auto-paren-balance</tt></span>
<p>
<p>The value of <tt>ee-auto-paren-balance</tt> is a boolean value that determines
whether the expression editor automatically corrects a close
parenthesis or bracket, when typed, to match the corresponding open
parenthesis or bracket, if any.
Its default value is <tt>#t</tt>.
<p>
<a name="./expeditor:s4"></a><span class=formdef><b>global parameter</b>: <tt>ee-flash-parens</tt></span>
<p>
<p>The value of <tt>ee-flash-parens</tt> is a boolean value that determines
whether the expression editor briefly moves the cursor when an open
or close parenthesis or bracket is typed to the
matching close or open parenthesis or bracket (if any).
Its default value is <tt>#t</tt>.
<p>
<a name="./expeditor:s5"></a><span class=formdef><b>global parameter</b>: <tt>ee-paren-flash-delay</tt></span>
<p>
<p>The value of <tt>ee-paren-flash-delay</tt> is a nonnegative fixnum
value that determines the amount of time (in milliseconds) that the
expression editor pauses when the cursor is moved to the matching
parenthesis or bracket, if any, when a parenthesis or bracket is
entered.
The value is ignored if the <tt>ee-flash-parens</tt> is false.
Its default value is <tt>100</tt>.
<p>
<a name="./expeditor:s6"></a><span class=formdef><b>global parameter</b>: <tt>ee-default-repeat</tt></span>
<p>
<p>The value of <tt>ee-default-repeat</tt> is a nonnegative fixnum
value that determines the number of of times the next command is
repeated after the <tt>ee-command-repeat</tt> editing command
(bound to <tt>Esc-^U</tt> by default) is used and <i>not</i>
followed by a sequence of digits.
It's default value is <tt>4</tt>.
<p>
<a name="./expeditor:s7"></a><span class=formdef><b>global parameter</b>: <tt>ee-noisy</tt></span>
<p>
<p>The value of <tt>ee-noisy</tt> is a boolean value that determines
whether the expression editor emits a beep (bell) when an error
occurs, such as an attempt to find the matching delimiter for a
non-delimiter character.
Its default value is <tt>#f</tt>.
<p>
<a name="./expeditor:s8"></a><span class=formdef><b>global parameter</b>: <tt>ee-history-limit</tt></span>
<p>
<p>The value of <tt>ee-history-limit</tt> is a nonnegative fixnum value
that determines the number of history entries retained by the
expression editor during and across sessions.
Only the last <tt>(ee-history-limit)</tt> entries are retained.
<p>
<a name="./expeditor:s9"></a><span class=formdef><b>global parameter</b>: <tt>ee-common-identifiers</tt></span>
<p>
<p>The value of <tt>ee-common-identifiers</tt> is list of symbols that
are considered common enough that they should appear early when
one of the incremental identifier-completion editing commands is
invoked.
Its default value contains a few dozen entries.
They are all more than a few characters long (under the theory that
users will most likely type short ones out fully) and all would
appear later than they likely should when incremental
identifier-completion is used.
<p>
<h3><a name="g130"></a><a name="./expeditor:h2"></a>Section 14.2. Key Binding<a name="SECTEXPEDITORKEYBINDING"></a></h3>
<p>
Key bindings are established via <tt>ee-bind-key</tt>.
The default key bindings are described in Section <a href="./expeditor.html#g131">14.3</a>.
<p>
<a name="./expeditor:s10"></a><span class=formdef><b>procedure</b>: <tt>(ee-bind-key <i>key</i> <i>procedure</i>)</tt></span>
<p>
<br>
<b>returns: </b>unspecified
<p>The <tt>ee-bind-key</tt> procedure is used to add to or change the
set of key bindings recognized by the expression editor.
<p>
The <tt><i>key</i></tt> must be a character or string; if it is a string, it
must have the following form.
<p>
<table><tr><td nowrap>
<key-string></td><td align=center><img src="math/csug/2.gif" alt="<graphic>"></td><td nowrap><tt>"</tt><key-char><sup>+</sup><tt>"</tt>
</td></tr></table>
<p>
where
<p>
<table><tr><td nowrap>
<key-char></td><td align=center><img src="math/csug/2.gif" alt="<graphic>"></td><td nowrap><tt>\\e</tt> (specifying an escape character)</td></tr><tr><td nowrap>
</td><td align=center>|</td><td nowrap><tt>^<i>x</i></tt> (specifying control-<tt><i>x</i></tt>)</td></tr><tr><td nowrap>
</td><td align=center>|</td><td nowrap><tt>\\^</tt> (specifying caret)</td></tr><tr><td nowrap>
</td><td align=center>|</td><td nowrap><tt>\\\\</tt> (specifying back slash)</td></tr><tr><td nowrap>
</td><td align=center>|</td><td nowrap><tt>plain char</tt> (any character other than <tt>\</tt> or <tt>^</tt>)
</td></tr></table>
<p>
Note that each double-backslash in the syntax actually denotes just
one backslash in the string.
<p>
For example, the <tt><i>key</i></tt> <tt>"\\eX"</tt> represents the two-character
sequence Escape-x, i.e., the "escape" key followed by the (capital)
"X" key.
Similarly, they <tt><i>key</i></tt> <tt>"\\e^X"</tt> represents the two-character
sequence Escape-Control-x, i.e., the "escape" key followed by
Control-X.
<p>
Character keys and string keys consisting of a single plain character
always represent a single keystroke.
<p>
The <tt><i>procedure</i></tt> argument should normally be one of the built-in editing
commands described below.
It is also possible to define new editing commands with
<a name="./expeditor:s11"></a><tt>ee-string-macro</tt>
and <a name="./expeditor:s12"></a><tt>ee-compose</tt>.
<p>
<h3><a name="g131"></a><a name="./expeditor:h3"></a>Section 14.3. Editing Commands<a name="SECTEXPEDITOREDITCMDS"></a></h3>
<p>
<p>
The editing commands are grouped into sections according to usage.
Each is listed along with the default character sequence or sequences by
which it may be invoked.
<p>
<p><b>Insertion commands</b>
<p><p><b>command:</b> <a name="./expeditor:s13"></a><tt>ee-insert-self</tt><br>
<b>key(s):</b> most printing characters
<p>
Inserts the entered character into the entry.
<p><p><b>command:</b> <a name="./expeditor:s14"></a><tt>ee-insert-paren</tt><br>
<b>key(s):</b> <tt>(</tt>, <tt>)</tt>, <tt>[</tt>, <tt>]</tt>
<p>
Inserts the entered parenthesis or bracket into the entry.
<p>
If the parameter
<a name="./expeditor:s15"></a><tt>ee-auto-paren-balance</tt> is
true, the editor corrects close delimiters if necessary to balance
existing open delimiters, when a matching open delimiter can be found.
<p>
If the parameter <a name="./expeditor:s16"></a><tt>ee-flash-parens</tt>
is true, the editor briefly moves the cursor to the matching delimiter, if
one can be found, pausing for an amount of time controlled by the
parameter <a name="./expeditor:s17"></a><tt>ee-paren-flash-delay</tt>.
If the matching delimiter is not presently displayed, the cursor is flashed
to the upper-left or lower-left corner of the displayed portion of the
entry, as appropriate.
<p>
The behavior of this command is undefined if used for something other
than a parenthesis or bracket.
parentheses and brackets.
<p><p><b>command:</b> <a name="./expeditor:s18"></a><tt>ee-newline</tt><br>
<b>key(s):</b> none
<p>
Inserts a newline at the cursor position, moves to the next line, and
indents that line if the parameter
<a name="./expeditor:s19"></a><tt>ee-auto-indent</tt> is true.
Does nothing if the entry is empty.
See also <tt>ee-newline/accept</tt>.
<p><p><b>command:</b> <a name="./expeditor:s20"></a><tt>ee-open-line</tt><br>
<b>key(s):</b> <tt>^O</tt>
<p>
Inserts a newline at the cursor position and indents the next line,
but does not move to the next line.
<p><p><b>command:</b> <a name="./expeditor:s21"></a><tt>ee-yank-kill-buffer</tt><br>
<b>key(s):</b> <tt>^Y</tt>
<p>
Inserts the contents of the kill buffer, which is set by the deletion
commands described below.
<p><p><b>command:</b> <a name="./expeditor:s22"></a><tt>ee-yank-selection</tt><br>
<b>key(s):</b> <tt>^V</tt>
<p>
Inserts the contents of the window system's current selection or paste
buffer.
When running in a shell window under X Windows, this command requires that
the DISPLAY environment variable be set to the appropriate display.
<p>
<p><b>Cursor movement commands</b>
<p><p><b>command:</b> <a name="./expeditor:s23"></a><tt>ee-backward-char</tt><br>
<b>key(s):</b> leftarrow, <tt>^B</tt>
<p>
Moves the cursor left one character.
<p><p><b>command:</b> <a name="./expeditor:s24"></a><tt>ee-forward-char</tt><br>
<b>key(s):</b> rightarrow, <tt>^F</tt>
<p>
Moves the cursor right one character.
<p><p><b>command:</b> <a name="./expeditor:s25"></a><tt>ee-next-line</tt><br>
<b>key(s):</b> downarrow, <tt>^N</tt>
<p>
Moves the cursor down one line (and to the left if necessary so that
the cursor does not sit beyond the last possible position).
If the cursor is at the end of the current entry, and the current
entry has not been modified, this command behaves like
<a name="./expeditor:s26"></a><tt>ee-history-fwd</tt>.
<p><p><b>command:</b> <a name="./expeditor:s27"></a><tt>ee-previous-line</tt><br>
<b>key(s):</b> uparrow, <tt>^P</tt>
<p>
Moves the cursor up one line (and to the left if necessary so that
the cursor does not sit beyond the last possible position).
If the cursor is at the top of the current entry, and the current
entry has not been modified, this command behaves like
<a name="./expeditor:s28"></a><tt>ee-history-bwd</tt>.
<p><p><b>command:</b> <a name="./expeditor:s29"></a><tt>ee-beginning-of-line</tt><br>
<b>key(s):</b> home, <tt>^A</tt>
<p>
Moves the cursor to the first character of the current line.
<p><p><b>command:</b> <a name="./expeditor:s30"></a><tt>ee-end-of-line</tt><br>
<b>key(s):</b> end, <tt>^E</tt>
<p>
Moves the cursor to the right of the last character of the current line.
<p><p><b>command:</b> <a name="./expeditor:s31"></a><tt>ee-beginning-of-entry</tt><br>
<b>key(s):</b> escape-<tt><</tt>
<p>
Moves the cursor to the first character of the entry.
<p><p><b>command:</b> <a name="./expeditor:s32"></a><tt>ee-end-of-entry</tt><br>
<b>key(s):</b> escape-<tt>></tt>
<p>
Moves the cursor to the right of the last character of the entry.
<p><p><b>command:</b> <a name="./expeditor:s33"></a><tt>ee-goto-matching-delimiter</tt><br>
<b>key(s):</b> escape-<tt>]</tt>
<p>
Moves the cursor to the matching delimiter.
Has no effect if the character under the cursor is not a parenthesis
or bracket or if no matching delimiter can be found.
<p><p><b>command:</b> <a name="./expeditor:s34"></a><tt>ee-flash-matching-delimiter</tt><br>
<b>key(s):</b> <tt>^]</tt>
<p>
Moves the cursor briefly to the matching delimiter, if
one can be found, pausing for an amount of time controlled by the
parameter <a name="./expeditor:s35"></a><tt>ee-paren-flash-delay</tt>.
If the matching delimiter is not presently displayed, the cursor is flashed
to the upper-left or lower-left corner of the displayed portion of the
entry, as appropriate.
<p><p><b>command:</b> <a name="./expeditor:s36"></a><tt>ee-exchange-point-and-mark</tt><br>
<b>key(s):</b> <tt>^X</tt>-<tt>^X</tt>
<p>
Moves the cursor to the mark and leaves the mark at the old cursor
position.
(The mark can be set with <tt>ee-set-mark</tt>.)
<p><p><b>command:</b> <a name="./expeditor:s37"></a><tt>ee-forward-sexp</tt><br>
<b>key(s):</b> escape-<tt>^F</tt>
<p>
Moves the cursor to the start of the next expression.
<p><p><b>command:</b> <a name="./expeditor:s38"></a><tt>ee-backward-sexp</tt><br>
<b>key(s):</b> escape-<tt>^B</tt>
<p>
Moves the cursor to the start of the preceding expression.
<p><p><b>command:</b> <a name="./expeditor:s39"></a><tt>ee-forward-word</tt><br>
<b>key(s):</b> escape-f, escape-<tt>F</tt>
<p>
Moves the cursor to the end of the next word.
<p><p><b>command:</b> <a name="./expeditor:s40"></a><tt>ee-backward-word</tt><br>
<b>key(s):</b> escape-b, escape-<tt>B</tt>
<p>
Moves the cursor to the start of the preceding word.
<p><p><b>command:</b> <a name="./expeditor:s41"></a><tt>ee-forward-page</tt><br>
<b>key(s):</b> pagedown, <tt>^X</tt>-<tt>]</tt>
<p>
Moves the cursor down one screen page.
<p><p><b>command:</b> <a name="./expeditor:s42"></a><tt>ee-backward-page</tt><br>
<b>key(s):</b> pageup, <tt>^X</tt>-<tt>[</tt>
<p>
Moves the cursor up one screen page.
<p><p><b>Deletion commands</b>
<p><p><b>command:</b> <a name="./expeditor:s43"></a><tt>ee-delete-char</tt><br>
<b>key(s):</b> delete
<p>
Deletes the character under the cursor.
<p>
See also <tt>ee-eof/delete-char</tt>.
<p><p><b>command:</b> <a name="./expeditor:s44"></a><tt>ee-backward-delete-char</tt><br>
<b>key(s):</b> backspace (rubout), <tt>^H</tt>
<p>
Deletes the character to the left of the cursor.
<p><p><b>command:</b> <a name="./expeditor:s45"></a><tt>ee-delete-line</tt><br>
<b>key(s):</b> <tt>^U</tt>
<p>
Deletes the contents of the current line, leaving behind an empty line.
When used on the first line of a multiline entry of which only the first line
is displayed, i.e., immediately after history movement, <tt>ee-delete-line</tt>
deletes the contents of the entire entry, like <tt>ee-delete-entry</tt>
(described below).
<p><p><b>command:</b> <a name="./expeditor:s46"></a><tt>ee-delete-to-eol</tt><br>
<b>key(s):</b> <tt>^K</tt>, escape-<tt>K</tt>
<p>
If the cursor is at the end of a line, joins the line with the next
line, otherwise deletes from the cursor position to the end of the line.
<p><p><b>command:</b> <a name="./expeditor:s47"></a><tt>ee-delete-between-point-and-mark</tt><br>
<b>key(s):</b> <tt>^W</tt>
<p>
Deletes text between the current cursor position and the mark.
(The mark can be set with <tt>ee-set-mark</tt>.)
<p><p><b>command:</b> <a name="./expeditor:s48"></a><tt>ee-delete-entry</tt><br>
<b>key(s):</b> <tt>^G</tt>
<p>
Deletes the contents of the current entry.
<p><p><b>command:</b> <a name="./expeditor:s49"></a><tt>ee-reset-entry</tt><br>
<b>key(s):</b> <tt>^C</tt>
<p>
Deletes the contents of the current entry and moves to the end of the
history.
<p><p><b>command:</b> <a name="./expeditor:s50"></a><tt>ee-delete-sexp</tt><br>
<b>key(s):</b> escape-<tt>^K</tt>, escape-delete
<p>
Deletes the expression that starts under the cursor, or if
no expression starts under the cursor, deletes up to the next
expression.
<p><p><b>command:</b> <a name="./expeditor:s51"></a><tt>ee-backward-delete-sexp</tt><br>
<b>key(s):</b> escape-backspace (escape-rubout), escape-<tt>^H</tt>
<p>
Deletes the expression to the left of the cursor.
<p><p><b>Identifier/filename completion commands</b>
<p>These commands perform either identifier or filename completion.
Identifier completion is performed outside of a string constant, and filename
completion is performed within a string constant.
(In determining whether the cursor is within a string constant, the
expression editor looks only at the current line and so can be fooled
by string constants that span multiple lines.)
<p>
<p><b>command:</b> <a name="./expeditor:s52"></a><tt>ee-id-completion</tt><br>
<b>key(s):</b> none
<p>
Inserts the common prefix of possible completions of the identifier or
filename immediately to the left of the cursor.
Identifier completion is based on the identifiers
defined in the interaction environment.
When there is exactly one possible completion, the common prefix is the
completion.
This command has no effect if no filename or identifier prefix is
immediately the left of the cursor or if the possible completions have
no common prefix.
If run twice in succession, a list of possible completions is displayed.
<p>
See also
<a name="./expeditor:s53"></a><tt>ee-id-completion/indent</tt>.
<p><p><b>command:</b> <a name="./expeditor:s54"></a><tt>ee-next-id-completion</tt><br>
<b>key(s):</b> <tt>^R</tt>
<p>
Inserts one of the possible completions of the identifier or filename
immediately to the left of the cursor.
Identifier completion is based on the identifiers
defined in the interaction environment.
If run twice or more in succession, this command cycles through all of
the possible completions.
The order is determined by the following heuristics: appearing first
are identifiers whose names appear in the list value of the parameter
<a name="./expeditor:s55"></a><tt>ee-common-identifiers</tt>;
appearing second are identifiers bound in the interaction environment
but not bound in the scheme-environment (i.e., identifiers defined by
the user), and appearing last are those in the scheme environment.
Within the set of matches appearing in the <tt>ee-common-identifiers</tt>
list, those listed earliest are shown first; the order is alphabetical
within the other two sets.
<p>
See also
<a name="./expeditor:s56"></a><tt>ee-next-id-completion/indent</tt>.
<p><p><b>History movement commands</b>
<p><a name="./expeditor:s57"></a>The expression editor maintains a history of entries during each session.
It also saves the history across sessions unless this behavior is
disabled via the command-line argument "<tt>--eehistory off</tt>."
<p>
When moving from one history entry to another, only the first line of each
multi-line entry is displayed.
The redisplay command (which <tt>^L</tt> is bound to by default) can be used
to display the entire entry.
It is also possible to move down one line at a time to expose just part of
the rest of the entry.
<p>
<p><b>command:</b> <a name="./expeditor:s58"></a><tt>ee-history-bwd</tt><br>
<b>key(s):</b> escape-uparrow, escape-<tt>^P</tt>
<p>
Moves to the preceding history entry
if the current entry is empty or has not been modified;
otherwise, has no effect.
<p>
See also <tt>ee-previous-line</tt>.
<p><p><b>command:</b> <a name="./expeditor:s59"></a><tt>ee-history-fwd</tt><br>
<b>key(s):</b> escape-downarrow, escape-<tt>^N</tt>
<p>
Moves to the next history entry
if the current entry is empty or has not been modified;
otherwise, has no effect.
<p>
See also <tt>ee-next-line</tt>.
<p><p><b>command:</b> <a name="./expeditor:s60"></a><tt>ee-history-bwd-prefix</tt><br>
<b>key(s):</b> escape-<tt>p</tt>
<p>
Moves to the closest previous history entry, if any, that starts with
the sequence of characters that makes up the current entry.
May be used multiple times to search for same prefix.
<p><p><b>command:</b> <a name="./expeditor:s61"></a><tt>ee-history-fwd-prefix</tt><br>
<b>key(s):</b> escape-<tt>n</tt>
<p>
Moves to the closest following history entry, if any, that starts with
the sequence of characters that makes up the current entry.
May be used multiple times to search for same prefix.
<p><p><b>command:</b> <a name="./expeditor:s62"></a><tt>ee-history-bwd-contains</tt><br>
<b>key(s):</b> escape-<tt>P</tt>
<p>
Moves to the closest previous history entry, if any, that contains within
it the sequence of characters that makes up the current entry.
May be used multiple times to search for same content.
<p><p><b>command:</b> <a name="./expeditor:s63"></a><tt>ee-history-fwd-contains</tt><br>
<b>key(s):</b> escape-<tt>N</tt>
<p>
Moves to the closest following history entry, if any, that contains within
it the sequence of characters that makes up the current entry.
May be used multiple times to search for same content.
<p><p><b>Indentation commands</b>
<p><p><b>command:</b> <a name="./expeditor:s64"></a><tt>ee-indent</tt><br>
<b>key(s):</b> escape-tab
<p>
Re-indents the current line.
<p>
See also <tt>ee-next-id-completion/indent</tt>.
<p><p><b>command:</b> <a name="./expeditor:s65"></a><tt>ee-indent-all</tt><br>
<b>key(s):</b> escape-<tt>q</tt>, escape-<tt>Q</tt>, escape-<tt>^Q</tt>
<p>
Re-indents each line of the entire entry.
<p><p><b>Miscellaneous commands</b>
<p><p><b>command:</b> <a name="./expeditor:s66"></a><tt>ee-accept</tt><br>
<b>key(s):</b> <tt>^J</tt>
<p>
Causes the expression editor to invoke the Scheme reader on the contents
of the entry.
If the read is successful, the expression is returned to the waiter;
otherwise, an error message is printed, the entry redisplayed, and the
cursor left (if possible) at the start of the invalid subform.
<p>
See also <tt>ee-newline/accept</tt>.
<p><p><b>command:</b> <a name="./expeditor:s67"></a><tt>ee-eof</tt><br>
<b>key(s):</b> none
<p>
Causes end-of-file to be returned from the expression editor,
which in turn causes the waiter to exit.
Ignored unless entry is empty.
<p>
See also <tt>ee-eof/delete-char</tt>.
<p><p><b>command:</b> <a name="./expeditor:s68"></a><tt>ee-redisplay</tt><br>
<b>key(s):</b> <tt>^L</tt>
<p>
Redisplays the current expression.
If run twice in succession, clears the screen and redisplays the
expression at the top of the screen.
<p><p><b>command:</b> <a name="./expeditor:s69"></a><tt>ee-suspend-process</tt><br>
<b>key(s):</b> <tt>^Z</tt>
<p>
Suspends the current process in shells that support job control.
<p><p><b>command:</b> <a name="./expeditor:s70"></a><tt>ee-set-mark</tt><br>
<b>key(s):</b> <tt>^@</tt>, <tt>^</tt>space
<p>
Sets the mark to the current cursor position.
<p><p><b>command:</b> <a name="./expeditor:s71"></a><tt>ee-command-repeat</tt><br>
<b>key(s):</b> escape-<tt>^U</tt>
<p>
Repeats the next command <i>n</i> times.
If the next character typed is a digit, <i>n</i> is determined by reading
up the sequence of the digits typed and treating it as a decimal
number.
Otherwise, <i>n</i> is the value of the parameter
<a name="./expeditor:s72"></a><tt>ee-default-repeat</tt>.
<p><p><b>Combination commands</b>
<p><p><b>command:</b> <a name="./expeditor:s73"></a><tt>ee-newline/accept</tt><br>
<b>key(s):</b> enter, <tt>^M</tt>
<p>
Behaves like <tt>ee-accept</tt> if run at the end (not including
whitespace) of an entry that starts with a balanced expression;
otherwise, behaves like <tt>ee-newline</tt>.
<p><p><b>command:</b> <a name="./expeditor:s74"></a><tt>ee-id-completion/indent</tt><br>
<b>key(s):</b> tab
<p>
Behaves like <tt>ee-id-completion</tt> if an identifier (outside
a string constant) or filename (within a string constant) appears
just to the left of the cursor and the last character of that
identifier or filename was just entered;
otherwise, behaves like <tt>ee-indent</tt>.
<p>
If an existing identifier or filename, i.e., not one just typed, appears to the left
of the cursor, the first use of this command behaves like
<tt>ee-newline</tt>, the second consecutive use behaves like
<tt>ee-id-completion</tt>, and the third behaves like a second consecutive
use of <tt>ee-id-completion</tt>.
<p><p><b>command:</b> <a name="./expeditor:s75"></a><tt>ee-next-id-completion/indent</tt><br>
<b>key(s):</b> none
<p>
Behaves like <tt>ee-next-id-completion</tt> if an identifier (outside
a string constant) or filename (within a string constant)
appears just to the left of the cursor and the last character of that
identifier or identifier was just entered;
otherwise, behaves like <tt>ee-indent</tt>.
<p><p><b>command:</b> <a name="./expeditor:s76"></a><tt>ee-eof/delete-char</tt><br>
<b>key(s):</b> <tt>^D</tt>
<p>
Behaves like <tt>ee-delete-char</tt> if the entry is nonempty;
otherwise, behaves like <tt>ee-eof</tt>.
If the entry is nonempty and this command is run twice or more in
succession, it does nothing once the entry becomes empty.
This is to prevent accidental exit from the waiter in cases where
the command is run repeatedly (perhaps with the help of a keyboard's
auto-repeat feature) to delete all of the characters in an entry.
<p>
<h3><a name="g132"></a><a name="./expeditor:h4"></a>Section 14.4. Creating New Editing Commands<a name="SECTEXPEDITORNEWCMDS"></a></h3>
<p>
<a name="./expeditor:s77"></a><span class=formdef><b>procedure</b>: <tt>(ee-string-macro <i>string</i>)</tt></span>
<p>
<br>
<b>returns: </b>a new editing command
<p>The new editing command produced inserts <tt><i>string</i></tt> before the current
cursor position.
<p>
Two string macros are predefined:
<p>
<TABLE><TR><TD nowrap align="left">
<tt>(ee-string-macro "(define ")</tt> </TD><TD nowrap align="left"> escape-d</TD></TR><TR><TD nowrap align="left">
<tt>(ee-string-macro "(lambda ")</tt> </TD><TD nowrap align="left"> escape-l
</TD></TR></TABLE>
<p>
<a name="./expeditor:s78"></a><span class=formdef><b>procedure</b>: <tt>(ee-compose <i>ecmd</i> ...)</tt></span>
<p>
<br>
<b>returns: </b>a new editing command
<p>Each <tt><i>ecmd</i></tt> must be an editing command.
<p>
The new editing command runs each of the editing commands
<tt><i>ecmd</i> ...</tt> in sequence.
<p>
For example, the following expression binds <tt>^X</tt>-p to an editing
command that behaves like <tt>ee-history-bwd-prefix</tt> but leaves the
cursor at the end of the expression rather than at the end of the first
line, causing the entire entry to be displayed.
<p>
<p><tt>(let ()<br>
(import expression-editor)<br>
(ee-bind-key "^Xp"<br>
(ee-compose ee-history-bwd ee-end-of-entry)))</tt>
<p>A command such as <tt>ee-id-completion</tt> that performs a different
action when run twice in succession will not recognize that it has been
run twice in succession if run as part of a composite command.
<p>
<hr class=copyright align=left>
<p>
<a class=plain href="index.html">Chez Scheme Version 9 User's Guide</a><br>
Copyright © 2016 Cisco Systems, Inc.<br>
Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License Version 2.0</a>
(<a class=plain href="canned/copyright.html">full copyright notice.</a>).</br>
Revised June 2016 for Chez Scheme Version 9.4<br>
<a class=plain href="canned/about.html">about this book</a>
</tr></table>
</body>
</html>