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
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
|
<?xml version="1.0" encoding="iso-8859-1"?>
<!--
This file is part of groff, the GNU roff type-setting system.
Copyright (C) 2004, 2005, 2006, 2009 Free Software Foundation, Inc.
Written by Peter Schaffter.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3 or
any later version published by the Free Software Foundation; with the
Invariant Sections being this comment section, with no Front-Cover
Texts, and with no Back-Cover Texts.
A copy of the Free Documentation License is included as a file called
FDL in the main directory of the groff source package.
-->
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="content-type" content="text/html;charset=iso-8859-1"/>
<title>Mom -- Definitions and Terms</title>
</head>
<body bgcolor="#dfdfdf">
<!-- ==================================================================== -->
<a name="TOP"></a>
<p>
<a href="using.html#TOP">Next</a>
<a href="intro.html#TOP">Prev</a>
<a href="toc.html">Back to Table of Contents</a>
</p>
<a name="TERMS"><h1 align="center"><u>Definitions of terms used in this manual</u></h1></a>
<p>
<a href="#TERMS_TYPESETTING">Typesetting Terms</a>
<br/>
<a href="#TERMS_GROFF">Groff Terms</a>
<br/>
<a href="#TERMS_MOM">Mom Document Processing Terms</a>
</p>
<p>
I use a number of typesetting-specific and groff-specific terms
throughout this documentation, as well as a few terms that apply
to <strong>mom</strong> herself. To make life easier, I'll explain
them here. Refer back to this section should you encounter a word
or concept you're not familiar with.
</p>
<hr/>
<a name="TERMS_TYPESETTING"><h2><u>Typesetting terms</u></h2></a>
<ul>
<li><a href="#TERMS_ASCENDER">Ascender</a></li>
<li><a href="#TERMS_BASELINE">Baseline</a></li>
<li><a href="#TERMS_BALLOTBOX">Ballot box</a></li>
<li><a href="#TERMS_BULLET">Bullet</a></li>
<li><a href="#TERMS_CAPHEIGHT">Cap-height</a></li>
<li><a href="#TERMS_DESCENDER">Descender</a></li>
<li><a href="#TERMS_DISCRETIONARYHYPHEN">Discretionary hyphen</a></li>
<li><a href="#TERMS_DROPCAP">Drop cap</a></li>
<li><a href="#TERMS_EM">Em/en</a></li>
<li><a href="#TERMS_FAMILY">Family</a></li>
<li><a href="#TERMS_FIGURESPACE">Figure space/Digit space</a></li>
<li><a href="#TERMS_FIXEDWIDTHFONT">Fixed width font</a></li>
<li><a href="#TERMS_FIXEDWIDTHSPACE">Fixed width space</a></li>
<li><a href="#TERMS_FONT">Font</a></li>
<li><a href="#TERMS_FORCE">Force justify</a></li>
<li><a href="#TERMS_JUST">Justify/justification</a></li>
<li><a href="#TERMS_GUTTER">Gutter</a></li>
<li><a href="#TERMS_KERN">Kerning</a></li>
<li><a href="#TERMS_KERNUNIT">Kern Units</a></li>
<li><a href="#TERMS_LEADING">Lead/leading</a></li>
<li><a href="#TERMS_LEADER">Leaders</a></li>
<li><a href="#TERMS_LIGATURES">Ligature</a></li>
<li><a href="#TERMS_PICASPOINTS">Picas/Points</a></li>
<li><a href="#TERMS_PS">Point Size</a></li>
<li><a href="#TERMS_QUAD">Quad</a></li>
<li><a href="#TERMS_RAG">Rag</a></li>
<li><a href="#TERMS_SHAPE">Shape</a></li>
<li><a href="#TERMS_SOLID">Solid/set solid</a></li>
<li><a href="#TERMS_TRACKKERNING">Track kerning/Line kerning</a></li>
<li><a href="#TERMS_UNBREAKABLESPACE">Unbreakable space</a></li>
<li><a href="#TERMS_WEIGHT">Weight</a></li>
<li><a href="#TERMS_WORDSPACE">Word space</a></li>
<li><a href="#TERMS_XHEIGHT">x-height</a></li>
</ul>
<dl>
<dt><a name="TERMS_ASCENDER"><em>Ascender</em></a></dt>
<dd>
The portion of a letter that extends above the bowl. For
example, the letters a, c, and e have no ascenders. The letters
b, d, and h do.
</dd>
<dt><a name="TERMS_BASELINE"><em>Baseline</em></a></dt>
<dd>
The imaginary line on which the bottoms of capital letters and
the bowls of lower case letters rest.
</dd>
<dt><a name="TERMS_BALLOTBOX"><em>Ballot box</em></a></dt>
<dd>
An unfilled square, usually
<a href="#TERMS_CAPHEIGHT">cap-height</a>
in size, typically placed beside items in a checklist.
</dd>
<dt><a name="TERMS_BULLET"><em>Bullet</em></a></dt>
<dd>
A small, filled circle typically found beside items or points in
a list.
</dd>
<dt><a name="TERMS_CAPHEIGHT"><em>Cap-height</em></a></dt>
<dd>
The height of the tallest capital letter in a given
<a href="#TERMS_FONT">font</a>
at the current
<a href="#TERMS_PS">point size</a>.
</dd>
<dt><a name="TERMS_DESCENDER"><em>Descender</em></a></dt>
<dd>
The portion of a letter that extends beneath the
<a href="#TERMS_BASELINE">baseline</a>
(j, q, y are letters with descenders).
</dd>
<dt><a name="TERMS_DISCRETIONARYHYPHEN"><em>Discretionary hyphen</em></a></dt>
<dd>
A symbol inserted between two syllables of a word that indicates
to a typesetting program the valid hyphenation points in the
word. Normally, if hyphenation is turned on, groff knows where
to hyphenate words. However, hyphenation being what it is
(in English, at any rate), groff doesn't always get it right.
Discretionary hyphens make sure it does. In the event that the
word doesn't need to be hyphenated at all, groff leaves them
alone. In groff, the discretionary hyphen is entered with
<pre>
\% (backslash followed by a percent)
</pre>
</dd>
<dt><a name="TERMS_DROPCAP"><em>Drop cap</em></a></dt>
<dd>
A large, usually upper-case letter that introduces the first
paragraph of a document or section thereof. The top of the
drop cap usually lines up with the top of the first line of the
paragraph, and typically "drops" several lines lower.
Text adjacent to the drop cap is indented to the right of the
letter until the bottom of the drop cap is reached, at which
point text reverts to the left margin.
</dd>
<dt><a name="TERMS_EM"><em>Em/en</em></a></dt>
<dd>
An em is a relative measurement equal to the width of the
letter M at a given
<a href="#TERMS_PS">point size</a>
in a given
<a href="#TERMS_FONT">font</a>.
Since most Ms are designed square, an em is usually (but
sometimes erroneously) considered to be the same size as the
current point size (i.e. if the point size of the type is 12,
one em equals 12 points). An en is equal to the width of a
letter N (historically 2/3 of an em, although groff treats an en
as 1/2 of an em). Typically, ems and ens are used to measure
indents, or to define the length of dashes (long hyphens).
</dd>
<dt><a name="TERMS_FAMILY"><em>Family</em></a></dt>
<dd>
The collective name by which a collection of
<a href="#TERMS_FONT">fonts</a>
are known, e.g. Helvetica, Times Roman, Garamond.
</dd>
<dt><a name="TERMS_FIGURESPACE"><em>Figure space/Digit space</em></a></dt>
<dd>
A
<a href="#TERMS_FIXEDWIDTHSPACE">fixed width space</a>
that has the width of one digit. Used for aligning numerals in,
say, columns or numbered lists. In groff, the figure space is
entered with
<pre>
\0 (backslash followed by a zero)
</pre>
</dd>
<dt><a name="TERMS_FIXEDWIDTHFONT"><em>Fixed width font</em></a></dt>
<dd>
A family or font in which every character occupies exactly the
same amount of vertical space on the line. Courier is the
best-known, if not the most elegant, fixed-width font.
</dd>
<dt><a name="TERMS_FIXEDWIDTHSPACE"><em>Fixed width space</em></a></dt>
<dd>
Equal to
<a href="#TERMS_WORDSPACE">word space</a>,
but does not expand or contract when text is
<a href="#TERMS_JUST">justified</a>.
In groff, fixed width space is entered with
<pre>
\<space> (backslash followed by hitting the the spacebar on your keyboard)
</pre>
</dd>
<dt><a name="TERMS_FONT"><em>Font</em></a></dt>
<dd>
The specific
<a href="#TERMS_WEIGHT">weight</a>
and
<a href="#TERMS_SHAPE">shape</a>
of type within a
<a href="#TERMS_FAMILY">family</a>,
e.g. light, medium, bold (which are weights), and roman, italic,
condensed (which are shapes). By default, groff knows of four
fonts within its default set of families: R (medium roman), I
(medium italic), B (bold roman) and BI (bold italic).
<strong>Mom</strong> considerably extends this very basic list.
</dd>
<dt><a name="TERMS_FORCE"><em>Force justify</em></a></dt>
<dd>
Sometimes, in
<a href="#TERMS_JUST">justified</a>
text, a line needs to be broken short of the right margin.
Force justifying means telling a typesetting program (like
groff) that you want the line broken early AND that you want the
line's word spacing stretched to force the line flush with the
right margin.
</dd>
<dt><a name="TERMS_GUTTER"><em>Gutter</em></a></dt>
<dd>
The vertical whitespace separating columns of type.
</dd>
<dt><a name="TERMS_JUST"><em>Justify/justification</em></a></dt>
<dd>
Lines of type are justified when they're flush at both the left
and right margins. Justification is the act of making both
margins flush. Some people use the terms "left justified" and
"right justified" to mean type where only the left (or right)
margins align. I don't. See
<a href="#TERMS_QUAD">quad</a>.
</dd>
<dt><a name="TERMS_KERN"><em>Kerning</em></a></dt>
<dd>
Moving pairs of letters closer together to remove excess
whitespace between them. In the days before phototypesetting,
type was set from small, rectangular blocks of wood or metal,
each block having exactly one letter. Because the edge of
each block determined the edge of each letter, certain letter
combinations (TA, for example) didn't fit together well and had
to be mortised by hand to bring them visually closer. Modern
typesetting systems usually take care of kerning automatically,
but they're far from perfect. Professional typesetters still
devote a lot of time to fitting letters and punctuation together
properly.
</dd>
<dt><a name="TERMS_KERNUNIT"><em>Kern Units</em></a></dt>
<dd>
A relative distance equal to 1/36 of the current
<a href="#TERMS_PS">point size</a>.
Used between individual letters
for
<a href="#TERMS_KERN">kerning</a>.
Different typesetting systems use different values (1/54 is
popular), and sometimes call kern units by a different name.
<p>
<em><strong>Experts: </strong>A kern unit has nothing to do with
groff machine units.</em>
</p>
</dd>
<dt><a name="TERMS_LEADING"><em>Lead/leading</em></a></dt>
<dd>
The distance from the
<a href="#TERMS_BASELINE">baseline</a>
of one line of type to the line of type immediately beneath
it. Pronounced "ledding." Also called line spacing. Usually
measured in
<a href="#TERMS_PICASPOINTS">points</a>.
<p>
<em>In case you're interested...</em> In previous centuries,
lines of type were separated by thin strips of — you guessed
it — lead. Lines of type that had no lead between them were said
to be "set solid." Once you began separating them with
strips of lead, they were said to be "leaded", and the
spacing was expressed in terms of the number of
<a href="#TERMS_PICASPOINTS">points</a>
of lead. For this reason, "leading" and "line
spacing" aren't, historically speaking, synonymous.
If type was set 10 on 12, for example, the leading was 2
points, not 12. Nowadays, however, the two terms are used
interchangeably to mean the distance from baseline to baseline.
</p>
</dd>
<dt><a name="TERMS_LEADER"><em>Leaders</em></a></dt>
<dd>
Single characters used to fill lines, usually to their end. So
called because they "lead" the eye from one element
of the page to another. For example, in the following (brief)
Table of Contents, the periods (dots) are leaders.
<pre>
Foreword............... 2
Chapter 1.............. 5
Chapter 2.............. 38
Chapter 3.............. 60
</pre>
</dd>
<dt><a name="TERMS_LIGATURES"><em>Ligature</em></a></dt>
<dd>
Ligatures are letters joined together to form a single
character. The commonest are fi, fl, ff, ffi and ffl. Others
are ae and oe. Occasionally, one sees an st ligature, but this
is archaic and quite rare.
</dd>
<dt><a name="TERMS_PICASPOINTS"><em>Picas/Points</em></a></dt>
<dd>
There are twelve points in a pica, and six picas in an inch
(hence 72 points to the inch). In the same way that gem-dealers
have always used their own system of measurement for weight
(carats), typographers have always used their own system of
measurement for type.
</dd>
<dt><a name="TERMS_PS"><em>Point Size</em></a></dt>
<dd>
The nominal size of type, measured in
<a href="#TERMS_PICASPOINTS">points</a>
from the bottom of the longest
<a href="#TERMS_DESCENDER">descender</a>
to the top of the highest
<a href="#TERMS_ASCENDER">ascender</a>.
In reality, type is always fractionally smaller than its point
size.
</dd>
<dt><a name="TERMS_QUAD"><em>Quad</em></a></dt>
<dd>
When only one margin of type is flush, lines of type are quadded
in the direction of the flush margin. Therefore, quad left
means the left margin is flush, the right isn't. Quad right
means the right margin is flush, the left isn't. Quad centre
means neither the left nor the right margin is flush; rather,
lines of type are quadded on both sides so that type appears
centred on the page.
</dd>
<dt><a name="TERMS_RAG"><em>Rag</em></a></dt>
<dd>
Describes a margin that isn't flush. Rag right means the right
margin isn't flush. Rag left means the left margin isn't flush.
The expression "flush left/rag right" is sometimes used to
describe type that is
<a href="#TERMS_QUAD">quadded</a>
left.
</dd>
<dt><a name="TERMS_SHAPE"><em>Shape</em></a></dt>
<dd>
The degree of slant and/or the width of characters.
(Technically speaking, this is not a proper typesetting term;
however, it may help clarify some concepts presented in these
documents.)
<p>
Some typical shapes are:
<ul>
<li>"Roman", which has no slant, and has letterforms of
average width</li>
<li>"Italic", which is slanted, and has letterforms
of average width</li>
<li>"Condensed", which has no slant, but has
letterforms narrower than the average represented by Roman</li>
<li>"Condensed Italic", which is slanted, with letterforms narrower
than average</li>
</ul>
</p>
<p>
The term
<a href="#TERMS_FONT">font</a>,
as it is used in these documents, refers to a combination of
<a href="#TERMS_WEIGHT">weight</a>
and shape.
</p>
</dd>
<dt><a name="TERMS_SOLID"><em>Solid/set solid</em></a></dt>
<dd>
When no
<a href="#TERMS_LEADING">lead</a>
is added between lines of type (i.e. the
<a href="#TERMS_PS">point size</a>
and linespacing are the same), the lines are said to be "set
solid."
</dd>
<dt><a name="TERMS_TRACKKERNING"><em>Track kerning/Line kerning</em></a></dt>
<dd>
Sometimes, it's advantageous to increase or decrease the amount
of space between every letter in a line by an equal (usually
small) amount, in order to fit more (or fewer) characters on the
line. The correct term is letter spacing, but track kerning and
line kerning (and sometimes, just "kerning") have come to mean
the same thing.
</dd>
<dt><a name="TERMS_UNBREAKABLESPACE"><em>Unbreakable space</em></a></dt>
<dd>
Equal to
<a href="#TERMS_WORDSPACE">word space</a>,
however words separated by an unbreakable space will always be
kept together on the same line. Expands and contracts like word
space. Useful for proper names, which one should, whenever
possible, avoid splitting onto two lines. In groff, unbreakable
space is entered with
<pre>
\~ (backslash followed by a tilde)
</pre>
</dd>
<dt><a name="TERMS_WEIGHT"><em>Weight</em></a></dt>
<dd>
The thickness of the strokes of letterforms. Medium and Book
have average thicknesses and are the weights used for most
of the text in books, magazines, newspapers, etc. Light has
strokes slightly thinner than Medium or Book, but is still
acceptable for most text. Semibold, Bold, Heavy and Black all
have strokes of increasing thickness, making them suitable for
heads, subheads, headlines and the like.
</dd>
<dt><a name="TERMS_WORDSPACE"><em>Word space</em></a></dt>
<dd>
The amount of whitespace between words. When text is
<a href="#TERMS_JUST">justified</a>,
word space expands or contracts to make the margins flush.
</dd>
<dt><a name="TERMS_XHEIGHT"><em>x-height</em></a></dt>
<dd>
The height of a lower case letter x in a given font at a given
point size. Generally used to mean the average height of the
bowl of lower case letters.
</dd>
</dl>
<hr/>
<a name="TERMS_GROFF"><h2><u>Groff terms</u></h2></a>
<ul>
<li><a href="#TERMS_ALIAS">Alias</a></li>
<li><a href="#TERMS_ARGUMENTS">Arguments</a></li>
<li><a href="#TERMS_COMMENTLINES">Comment lines</a></li>
<li><a href="#TERMS_CONTROLLINES">Control Lines</a></li>
<li><a href="#TERMS_FILLED">Filled lines</a></li>
<li><a href="#TERMS_INLINES">Inline escapes</a></li>
<li><a href="#TERMS_INPUTLINE">Input line</a></li>
<li><a href="#TERMS_MACROS">Macros</a></li>
<li><a href="#TERMS_UNITS">Machine units</a></li>
<li><a href="#TERMS_NUMERICARGUMENT">Numeric argument</a></li>
<li><a href="#TERMS_OUTPUTLINE">Output line</a></li>
<li><a href="#TERMS_PRIMITIVES">Primitives</a></li>
<li><a href="#TERMS_STRINGARGUMENT">String Argument</a></li>
<li><a href="#TERMS_UNITOFMEASURE">Unit of measure</a></li>
<li><a href="#TERMS_ZEROWIDTHCHARACTER">Zero-width character</a></li>
</ul>
<dl>
<dt><a name="TERMS_ALIAS"><em>Alias</em></a></dt>
<dd>
A
<a href="#TERMS_MACROS">macro</a>
invoked by a name different from its "official"
name. For example, the official name of the macro to change
<a href="#TERMS_FAMILY">family</a>
is <strong>FAMILY</strong>. Its alias is <strong>FAM</strong>.
Aliases may be created for any macro (via the
<a href="goodies.html#ALIAS">ALIAS</a>
macro) provided the alias uses a name not already taken by the
<strong>mom</strong> macros or one of the groff
<a href="#TERMS_PRIMITIVES">primitives</a>.
For a complete list of words or names you must not use, see the
<a href="reserved.html#RESERVED">list of reserved words</a>.
</dd>
<dt><a name="TERMS_ARGUMENTS"><em>Arguments</em></a></dt>
<dd>
Parameters or information needed by a
<a href="#TERMS_MACROS">macro</a>
to do its job. For example, in the macro
<pre>
.PT_SIZE 12
</pre>
<kbd>12</kbd> is the argument. In the macro
<pre>
.QUAD LEFT
</pre>
<kbd>LEFT</kbd> is the argument. Arguments are separated from
macros by spaces. Some macros require several arguments; each
is separated by a space.
</dd>
<dt><a name="TERMS_COMMENTLINES"><em>Comment Lines</em></a></dt>
<dd>
<a href="#TERMS_INPUTLINE">Input lines</a>
introduced with the comment character
<pre>
\# (backslash followed by the pound sign)
</pre>
When processing output, groff silently ignores everything on a
line that begins with the comment character.
</dd>
<dt><a name="TERMS_CONTROLLINES"><em>Control Lines</em></a></dt>
<dd>
Instructions to groff that appear on a line by themselves, which
means that "control lines" are either
<a href="#TERMS_MACROS">macros</a>
or groff
<a href="#TERMS_PRIMITIVES">primitives</a>.
Control lines begin with a period or, occasionally, an apostrophe.
</dd>
<dt><a name="TERMS_FILLED"><em>Filled lines/fill mode</em></a></dt>
<dd>
Automatic
<a href="#TERMS_JUST">justification</a>
or
<a href="#TERMS_QUAD">quadding</a>.
In fill mode, the ends of lines as they appear in your text
editor are ignored. Instead, words from adjoining
<a href="#TERMS_INPUTLINE">input lines</a>
are added one at a time to the output line until no more words
fit. Then, depending whether text is to be
<a href="#TERMS_JUST">justified</a>
or
<a href="#TERMS_QUAD">quadded</a>
(left, right, or centre), and depending on whether automatic
hyphenation is turned on, groff attempts to hyphenate the last
word, or, barring that, spreads and breaks the line (when
justification is turned on) or breaks and quads the line (when
quadding is turned on).
<p>
<a name="TERMS_NOFILL"></a>
Nofill mode (non-filled text) means that groff respects the ends
of lines as they appear in your text editor.
</p>
</dd>
<dt><a name="TERMS_INLINES"><em>Inline escapes</em></a></dt>
<dd>
Instructions issued to groff that appear as part of an
<a href="#TERMS_INPUTLINE">input line</a>
(as opposed to
<a href="#TERMS_MACROS">macros</a>,
which must appear on a line by themselves). Inline escapes are
always introduced by the backslash character. For example,
<pre>
A line of text with the word T\*[BU 2]oronto in it
</pre>
contains the inline escape <kbd>\*[BU 2]</kbd> (which means
"move the letter 'o' 2
<a href="#TERMS_KERNUNIT">kern units</a>
closer to the letter 'T'").
<p>
<strong>Mom</strong>'s inline escapes always take the form
<kbd>\*[<ESCAPE>]</kbd>, where <kbd>ESCAPE</kbd> is
composed of capital letters, sometimes followed immediately by a
digit, sometimes followed by a space and a
<a href="#TERMS_NUMERICARGUMENT">numeric argument</a>.
<strong>Groff</strong>'s escapes begin with the backslash
character but typically have no star and are in lower case. For
example, the <strong>mom</strong> escapes to move forward 6
points on a line are either
<pre>
\*[FP6] or \*[FWD 6p]
</pre>
while the <strong>groff</strong> escape for the same thing is
<pre>
\h'6p'
</pre>
</p>
</dd>
<dt><a name="TERMS_INPUTLINE"><em>Input line</em></a></dt>
<dd>
A line of text as it appears in your text editor.
</dd>
<dt><a name="TERMS_MACROS"><em>Macros</em></a></dt>
<dd>
Instructions embedded in a document that determine how groff
processes the text for output. <strong>mom</strong>'s macros
always begin with a period, on a line by themselves, and must
be typed in capital letters. Typically, macros contain complex
commands issued to groff — behind the scenes — via
groff
<a href="#TERMS_PRIMITIVES">primitives</a>.
</dd>
<dt><a name="TERMS_UNITS"><em>Machine units</em></a></dt>
<dd>
A machine unit is 1/1000 of a
<a href="#TERMS_PICASPOINTS">point</a>
when the groff device is ps. ("ps" means
"PostScript" — the default device for
which groff prepares output, and the device for which
<strong>mom</strong> was specifically designed.)
</dd>
<dt><a name="TERMS_NUMERICARGUMENT"><em>Numeric argument</em></a></dt>
<dd>
An
<a href="#TERMS_ARGUMENTS">argument</a>
that has the form of a digit. Numeric arguments can be built
out of arithmetic expressions using +, -, *, and / for plus,
minus, times, and divided-by respectively. If a numeric
argument requires a
<a href="#TERMS_UNITOFMEASURE">unit of measure</a>,
a unit of measure must be appended to <em>every</em> digit in
the argument. For example:
<pre>
.ALD 1i-1v
</pre>
<strong>NOTE:</strong> groff does not respect the order of
operations, but rather evaluates arithmetic expressions
from left to right. Parentheses must be used to circumvent
this peculiarity. Not to worry, though. The likelihood of
more than just the occasional plus or minus sign when using
<strong>mom</strong>'s macros is slim.
</dd>
<dt><a name="TERMS_OUTPUTLINE"><em>Output line</em></a></dt>
<dd>
A line of text as it appears in output copy.
</dd>
<dt><a name="TERMS_PRIMITIVES"><em>Primitives</em></a></dt>
<dd>
The lowercase instructions, introduced with a period, that groff
uses as its native command language, and out of which macros
are built. The majority of groff's primitive requests are two
letters long.
</dd>
<dt><a name="TERMS_STRINGARGUMENT"><em>String Argument</em></a></dt>
<dd>
Technically, any
<a href="#TERMS_ARGUMENTS">argument</a>
that is not numeric. In this documentation, string argument
means an argument that requires the user to input text. For
example, in the
<a href="#TERMS_MACROS">macro</a>
<pre>
.TITLE "My Pulitzer Novel"
</pre>
<kbd>My Pulitzer Novel</kbd> is a string argument.
<p>
Because string arguments must be enclosed by double-quotes, you
can't use double-quotes as part of the string argument. If you
need double-quotes to be part of a string argument, use the
<a href="#TERMS_INLINES">inline escapes</a>
<strong>\(lq</strong> and <strong>\(rq</strong> (leftquote and
rightquote respectively) in place of the double-quote character
(<strong>"</strong>).
</p>
</dd>
<dt><a name="TERMS_UNITOFMEASURE"><em>Unit of measure</em></a></dt>
<dd>
The single letter after a
<a href="#TERMS_NUMERICARGUMENT">numeric argument</a>
that tells <strong>mom</strong> what measurement scale the
argument should use. Common valid units are:
<pre>
i (inches)
p (points)
P (Picas)
c (centimetres)
m (ems)
n (ens)
u (machine units)
v (the current leading [line space])
</pre>
<p>
Units of measure must come immediately after the numeric
argument (i.e. with no space between the argument and the unit
of measure), like this:
<pre>
.ALD 2v
.LL 39P
.IL 1i
</pre>
The above example advances 2 line spaces and sets the line
length to 39 picas with a left indent of 1 inch.
</p>
<p>
<strong>IMPORTANT:</strong> Most <strong>mom</strong> macros
that set the size or measure of something MUST be given a
unit of measure. <strong>mom</strong>'s macros do not have
default units of measure. There are a couple of exceptions,
the most notable of which are <strong>PT_SIZE</strong> and
<strong>LS</strong>. Both use
<a href="#TERMS_PICASPOINTS">points</a>
as the default unit of measure, which means you don't have to
append "p" to their argument.
</p>
<p>
You can enter decimal values for any unit of measure. Different
units may be combined by adding them together (e.g. 1.5i+2m,
which gives a measure of 1-1/2 inches plus 2 ems).
</p>
<p>
<strong>NOTE:</strong> a pica is composed of 12 points,
therefore 12.5 picas is 12 picas and 6 points, not 12 picas and
5 points. If you want 12 picas and 5 points, you have to enter
the measure as 12P+5p.
</p>
</dd>
<dt><a name="TERMS_ZEROWIDTHCHARACTER"><em>Zero-width character</em></a></dt>
<dd>
The
<a href="#TERMS_INLINES">inline escape</a>
that allows you to print a literal period, apostrophe and, if
<a href="#TERMS_OUTPUTLINE">output lines</a>
are
<a href="#TERMS_FILLED">filled</a>,
a space that falls at the beginning of an
<a href="#TERMS_INPUTLINE">input line</a>.
It looks like this:
<pre>
\& (backslash followed by an ampersand)
</pre>
Normally, groff interprets a period (or an apostrophe) at the
beginning of an input line as meaning that what follows is a
<a href="#TERMS_CONTROLLINES">control line</a>.
In fill modes, groff treats a space at the beginning of an input
line as meaning "start a new line and put a space at the
beginning of it." If you want groff to interpret periods
and apostrophes at the beginning of input lines literally (i.e.
print them), or spaces at the beginning of input lines as just
garden variety word spaces, you must start the line with the
zero-width character.
</dd>
</dl>
<hr/>
<a name="TERMS_MOM"><h2><u>Mom's Document Processing Terms</u></h2></a>
<ul>
<li><a href="#TERMS_BLOCKQUOTE">Blockquote</a></li>
<li><a href="#TERMS_CONTROLMACRO">Control macro</a></li>
<li><a href="#TERMS_DOCHEADER">Docheader</a></li>
<li><a href="#TERMS_EPIGRAPH">Epigraph</a></li>
<li><a href="#TERMS_FOOTER">Footer</a></li>
<li><a href="#TERMS_HEAD">Head</a></li>
<li><a href="#TERMS_HEADER">Header</a></li>
<li><a href="#TERMS_LINEBREAK">Linebreak</a></li>
<li><a href="#TERMS_PARAHEAD">Paragraph head</a></li>
<li><a href="#TERMS_QUOTE">Quote</a></li>
<li><a href="#TERMS_RUNNING">Running text</a></li>
<li><a href="#TERMS_SUBHEAD">Subhead</a></li>
<li><a href="#TERMS_TOGGLE">Toggle</a></li>
</ul>
<dl>
<dt><a name="TERMS_BLOCKQUOTE"><em>Blockquote</em></a></dt>
<dd>
Cited material other than
<a href="#TERMS_QUOTE">quotes</a>.
Typically set at a smaller point size than paragraph text,
indented from the left and right margins. Blockquotes are
<a href="#TERMS_FILLED">filled</a>.
</dd>
<dt><a name="TERMS_CONTROLMACRO"><em>Control macro</em></a></dt>
<dd>
Macros used in
<a href="docprocessing.html#DOCPROCESSING">document processing</a>
to control/alter the appearance of document elements (e.g.
heads, quotes, footnotes,
<a href="#TERMS_HEADER">headers</a>,
etc.).
</dd>
<dt><a name="TERMS_DOCHEADER"><em>Document header/docheader</em></a></dt>
<dd>
Document information (title, subtitle, author, etc) output at
the top of page one.
</dd>
<dt><a name="TERMS_EPIGRAPH"><em>Epigraph</em></a></dt>
<dd>
A short, usually cited passage that appears at the beginning of
a chapter, story, or other document.
</dd>
<dt><a name="TERMS_FOOTER"><em>Footer/page footer</em></a></dt>
<dd>
Document information (frequently author and title) output in
the bottom margin of pages <em>after</em> page one. Not to be
confused with footnotes, which are considered part of
<a href="#TERMS_RUNNING">running text</a>.
</dd>
<dt><a name="TERMS_HEAD"><em>Head</em></a></dt>
<dd>
A title that introduces a major section of a document.
</dd>
<dt><a name="TERMS_HEADER"><em>Header/page header</em></a></dt>
<dd>
Document information (frequently author and title) output in the
top margin of pages <em>after</em> page one.
<p>
<strong>NOTE:</strong> In terms of content and style, headers
and
<a href="#TERMS_FOOTER">footers</a>
are the same; they differ only in their placement on the page.
In most places in this documentation, references to the content
or style of headers applies equally to footers.
</p>
</dd>
<dt><a name="TERMS_LINEBREAK"><em>Linebreak/author linebreak</em></a></dt>
<dd>
A horizontal gap in
<a href="#TERMS_RUNNING">running text</a>,
frequently set off by typographic symbols such as asterisks or
daggers. Used to indicate a shift in the content of a document
(e.g. a scene change in a short story). Also commonly called a
scene break or a section break.
</dd>
<dt><a name="TERMS_PARAHEAD"><em>Paragraph head</em></a></dt>
<dd>
A title joined to the body of a paragraph; hierarchically one
level beneath
<a href="#TERMS_SUBHEAD">subheads</a>.
</dd>
<dt><a name="TERMS_QUOTE"><em>Quote</em></a></dt>
<dd>
A quote, to <strong>mom</strong>, is a line-for-line setting
of quoted material (e.g. poetry, song lyrics, or a snippet of
programming code). You don't have to use
<a href="typesetting.html#BR">BR</a>
with quotes.
</dd>
<dt><a name="TERMS_RUNNING"><em>Running text</em></a></dt>
<dd>
In a document formatted with <strong>mom</strong>, running
text means text that forms the body of the document, including
elements such as heads and subheads.
<a href="#TERMS_DOCHEADER">Docheaders</a>,
<a href="#TERMS_HEADER">headers</a>,
<a href="#TERMS_FOOTER">footers</a>
and page numbers are NOT part of running text.
</dd>
<dt><a name="TERMS_SUBHEAD"><em>Subhead</em></a></dt>
<dd>
A title used to introduce secondary sections of a document;
hierarchically one level beneath sections introduced by
<a href="#TERMS_HEAD">heads</a>.
</dd>
<dt><a name="TERMS_TOGGLE"><em>Toggle</em></a></dt>
<dd>
A macro or tag that, when invoked without an argument, begins
something or turns a feature on, and, when invoked with ANY
argument, ends something or turns a feature off. See
<a href="intro.html#TOGGLE_EXAMPLE">Example 3</a>
of the section
<a href="intro.html#MACRO_ARGS">How to read macro arguments</a>.
</dd>
</dl>
<hr/>
<p>
<a href="using.html#TOP">Next</a>
<a href="intro.html#TOP">Prev</a>
<a href="#TOP">Top</a>
<a href="toc.html">Back to Table of Contents</a>
</p>
</body>
</html>
<!-- vim: fileencoding=latin1: nomodified:
-->
|
