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diff --git a/contrib/mom/momdoc/definitions.html b/contrib/mom/momdoc/definitions.html new file mode 100644 index 0000000..b85a089 --- /dev/null +++ b/contrib/mom/momdoc/definitions.html @@ -0,0 +1,995 @@ +<?xml version="1.0" encoding="utf-8"?> +<!-- +This file is part of groff, the GNU roff type-setting system. + +Copyright (C) 2004-2020 Free Software Foundation, Inc. +Written by Peter Schaffter (peter@schaffter.ca). + +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 no +Invariant Sections, 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=utf-8"/> + <title>Mom -- Definitions and Terms</title> + <link rel="stylesheet" type="text/css" href="stylesheet.css" /> +</head> + +<body style="background-color: #f5faff;"> + +<!-- ==================================================================== --> + +<div id="top" class="page"> + +<!-- Navigation links --> +<table style="width: 100%;"> + <tr> + <td><a href="toc.html">Back to Table of Contents</a></td> + <td style="text-align: right;"><a href="using.html#top">Next: Using mom</a></td> + </tr> +</table> + +<h1 id="terms" class="docs">Definitions of terms used in this manual</h1> + +<p> +I use a number of typesetting-specific and groff-specific terms +throughout this documentation, as well as a few terms that apply +to mom 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> + +<div class="rule-short" style="margin-top: 18px; margin-bottom: 28px;"><hr/></div> + +<div class="col-1-definitions"> + <table class="definitions"> + <tr><th class="definitions">Typesetting terms</th></tr> + <tr> + <td> + <a href="#ascender">Ascender</a><br/> + <a href="#baseline">Baseline</a><br/> + <a href="#ballotbox">Ballot box</a><br/> + <a href="#bullet">Bullet</a><br/> + <a href="#capheight">Cap-height</a><br/> + <a href="#descender">Descender</a><br/> + <a href="#discretionaryhyphen">Discretionary hyphen</a><br/> + <a href="#dropcap">Drop cap</a><br/> + <a href="#em">Em/en</a><br/> + <a href="#family">Family</a><br/> + <a href="#figurespace">Figure space/Digit space</a><br/> + <a href="#fixedwidthfont">Fixed width font</a><br/> + <a href="#fixedwidthspace">Fixed width space</a><br/> + <a href="#font">Font</a><br/> + <a href="#force">Force justify</a><br/> + <a href="#just">Justify/justification</a><br/> + <a href="#gutter">Gutter</a><br/> + <a href="#kern">Kerning</a><br/> + <a href="#kernunit">Kern Units</a><br/> + <a href="#leading">Lead/leading</a><br/> + <a href="#leader">Leaders</a><br/> + <a href="#ligatures">Ligature</a><br/> + <a href="#picaspoints">Picas/Points</a><br/> + <a href="#ps">Point Size</a><br/> + <a href="#quad">Quad</a><br/> + <a href="#rag">Rag</a><br/> + <a href="#shape">Shape</a><br/> + <a href="#solid">Solid/set solid</a><br/> + <a href="#trackkerning">Track kerning/Line kerning</a><br/> + <a href="#unbreakablespace">Unbreakable space</a><br/> + <a href="#weight">Weight</a><br/> + <a href="#wordspace">Word space</a><br/> + <a href="#xheight">x-height</a><br/> + </td> + </tr> + </table> +</div> + +<div class="col-2-definitions"> + <table class="definitions"> + <tr><th class="definitions">Groff terms</th></tr> + <tr> + <td> + <a href="#alias">Alias</a><br/> + <a href="#arguments">Arguments</a><br/> + <a href="#commentlines">Comment lines</a><br/> + <a href="#controllines">Control Lines</a><br/> + <a href="#filled">Filled lines</a><br/> + <a href="#inlines">Inline escapes</a><br/> + <a href="#inputline">Input line</a><br/> + <a href="#macros">Macros</a><br/> + <a href="#units">Machine units</a><br/> + <a href="#numericargument">Numeric argument</a><br/> + <a href="#outputline">Output line</a><br/> + <a href="#primitives">Primitives</a><br/> + <a href="#preprocessor">Pre-processor</a><br/> + <a href="#stringargument">String Argument</a><br/> + <a href="#unitofmeasure">Unit of measure</a><br/> + <a href="#zerowidthcharacter">Zero-width character</a><br/> + </td> + </tr> + </table> +</div> + +<div class="col-3-definitions"> + <table class="definitions"> + <tr><th class="definitions">Mom terms</th></tr> + <tr> + <td> + <a href="#baseline-grid">Baseline grid</a><br/> + <a href="#blockquote">Blockquote</a><br/> + <a href="#controlmacro">Control macro</a><br/> + <a href="#docheader">Docheader</a><br/> + <a href="#epigraph">Epigraph</a><br/> + <a href="#float">Float</a><br/> + <a href="#footer">Footer</a><br/> + <a href="#head">Head</a><br/> + <a href="#header">Header</a><br/> + <a href="#linebreak">Linebreak</a><br/> + <a href="#parahead">Paragraph head</a><br/> + <a href="#pdflink">PDF link</a><br/> + <a href="#pdfoutline">PDF outline</a><br/> + <a href="#quote">Quote</a><br/> + <a href="#running">Running text</a><br/> + <a href="#toggle">Toggle</a><br/> + </td> + </tr> + </table> +</div> + +<h3 id="typesetting-terms" class="docs">Typesetting terms</h3> +<dl> + <dt id="ascender">Ascender</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 id="baseline">Baseline</dt> + <dd> + The imaginary line on which the bottoms of capital letters and + the bowls of lower case letters rest. + </dd> + + <dt id="ballotbox">Ballot box</dt> + <dd> + An unfilled square, usually + <a href="#capheight">cap-height</a> + in size, typically placed beside items in a checklist. + </dd> + + <dt id="bullet">Bullet</dt> + <dd> + A small, filled circle typically found beside items or points in + a list. + </dd> + + <dt id="capheight">Cap-height</dt> + <dd> + The height of the tallest capital letter in a given + <a href="#font">font</a> + at the current + <a href="#ps">point size</a>. + </dd> + + <dt id="descender">Descender</dt> + <dd> + The portion of a letter that extends beneath the + <a href="#baseline">baseline</a> + (j, q, y are letters with descenders). + </dd> + + <dt id="discretionaryhyphen">Discretionary hyphen</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 + <kbd>\%</kbd> (i.e. a backslash followed by the percent sign). + </dd> + + <dt id="dropcap">Drop cap</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 id="em">Em/en</dt> + <dd> + An em is a relative measurement equal to the width of the + letter M at a given + <a href="#ps">point size</a> + in a given + <a href="#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 id="family">Family</dt> + <dd> + The collective name by which a collection of + <a href="#font">fonts</a> + are known, e.g. Helvetica, Times Roman, Garamond. + </dd> + + <dt id="figurespace">Figure space/Digit space</dt> + <dd> + A + <a href="#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 <kbd>\0</kbd> (i.e. a backslash followed by a zero) + </dd> + + <dt id="fixedwidthfont">Fixed-width font</dt> + <dd> + A family or font in which every character occupies exactly the + same amount of horizontal space on the line. Courier is the + best-known, if not the most elegant, fixed-width font. + </dd> + + <dt id="fixedwidthspace">Fixed width space</dt> + <dd> + Equal to + <a href="#wordspace">word space</a>, + but does not expand or contract when text is + <a href="#just">justified</a>. + In groff, fixed width space is entered with + <kbd>\<space></kbd> (i.e. a backslash followed by a space) + </dd> + + <dt id="font">Font</dt> + <dd> + The specific + <a href="#weight">weight</a> + and + <a href="#shape">shape</a> + of type within a + <a href="#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). + Mom considerably extends this very basic list. + </dd> + + <dt id="force">Force justify</dt> + <dd> + Sometimes, in + <a href="#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 id="gutter">Gutter</dt> + <dd> + The vertical whitespace separating columns of type. + </dd> + + <dt id="just">Justify/justification</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="#quad">quad</a>. + </dd> + + <dt id="kern">Kerning</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 id="kernunit">Kern Units</dt> + <dd> + A relative distance, which, by default, is equal to 1/36 of the + current + <a href="#ps">point size</a>. + Used between individual letters for + <a href="#kern">kerning</a>. + Different typesetting systems use different values (1/54 is + popular), and sometimes call kern units by a different name. + It is possible to change the default size of the kern unit with the + <a href="inlines.html#kernunit">KERN_UNIT</a> + macro. + </dd> + + <dt id="leading">Lead/leading</dt> + <dd> + The distance from the + <a href="#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="#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="#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 id="leader">Leaders</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. + + <span class="pre" style="margin-bottom: -2em;"> + Foreword............... 2 + Chapter 1.............. 5 + Chapter 2.............. 38 + Chapter 3.............. 60 + </span> + </dd> + + <dt id="ligatures">Ligature</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 id="picaspoints">Picas/Points</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 id="ps">Point Size</dt> + <dd> + The nominal size of type, measured in + <a href="#picaspoints">points</a> + from the bottom of the longest + <a href="#descender">descender</a> + to the top of the highest + <a href="#ascender">ascender</a>. + In reality, type is always fractionally smaller than its point + size. + </dd> + + <dt id="quad">Quad</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 id="rag">Rag</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="#quad">quadded</a> + left. + </dd> + + <dt id="shape">Shape</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: + </p> + + <ul style="margin-top: -.5em; margin-bottom: -.5em"> + <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> + The term + <a href="#font">font</a>, + as it is used in these documents, refers to a combination of + <a href="#weight">weight</a> + and shape. + </p> + + </dd> + + <dt id="solid">Solid/set solid</dt> + <dd> + When no + <a href="#leading">lead</a> + is added between lines of type (i.e., the + <a href="#ps">point size</a> + and linespacing are the same), the lines are said to be “set + solid.” + </dd> + + <dt id="trackkerning">Track kerning/Line kerning</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 id="unbreakablespace">Unbreakable space</dt> + <dd> + Equal to + <a href="#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 <kbd>\~</kbd> (i.e. a backslash followed by a + tilde) + </dd> + + <dt id="weight">Weight</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 + headings and the like. + </dd> + + <dt id="wordspace">Word space</dt> + <dd> + The amount of whitespace between words. When text is + <a href="#just">justified</a>, + word space expands or contracts to make the margins flush. + </dd> + + <dt id="xheight">x-height</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> + +<h3 id="groff-terms" class="docs">Groff terms</h3> + +<dl> + <dt id="alias">Alias</dt> + <dd> + A + <a href="#macros">macro</a> + invoked by a name different from its “official” + name. For example, the official name of the macro to change + <a href="#family">family</a> + is <kbd>FAMILY</kbd>. Its alias is <kbd>FAM</kbd>. + Aliases may be created for any macro (via the + <a href="goodies.html#alias"><kbd>ALIAS</kbd></a> + macro) provided the alias uses a name not already taken by the + mom macros or one of the groff + <a href="#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 id="arguments">Arguments</dt> + <dd> + Parameters or information needed by a + <a href="#macros">macro</a> + to do its job. For example, in the macro + + <span class="pre" style="margin-bottom: -2em;"> + .PT_SIZE 12 + </span> + + <kbd>12</kbd> is the argument. In the macro + + <span class="pre" style="margin-bottom: -2em;"> + .QUAD LEFT + </span> + + <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 id="commentlines">Comment Lines</dt> + <dd> + <a href="#inputline">Input lines</a> + introduced with the comment character <kbd>\#</kbd> (i.e. a + backslash followed by the pound sign). When processing output, + groff silently ignores everything on a line that begins with the + comment character. + </dd> + + <dt id="controllines">Control Lines</dt> + <dd> + Instructions to groff that appear on a line by themselves, which + means that “control lines” are either + <a href="#macros">macros</a> + or groff + <a href="#primitives">primitives</a>. + Control lines begin with a period or, occasionally, an apostrophe. + </dd> + + <dt id="filled">Filled lines/fill mode</dt> + <dd> + Automatic + <a href="#just">justification</a> + or + <a href="#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="#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="#just">justified</a> + or + <a href="#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 id="no-fill"> + Nofill mode (non-filled text) means that groff respects the ends + of lines exactly as they appear in your text editor. + </p> + + </dd> + + <dt id="inlines">Inline escapes</dt> + <dd> + Instructions issued to groff that appear as part of an + <a href="#inputline">input line</a> + (as opposed to + <a href="#macros">macros</a>, + which must appear on a line by themselves). Inline escapes are + always introduced by the backslash character. For example, + + <span class="pre" style="margin-bottom: -2em;"> + A line of text with the word T\*[BU 2]oronto in it + </span> + + contains the inline escape <kbd>\*[BU 2]</kbd> (which means + “move the letter ‘o’ 2 + <a href="#kernunit">kern units</a> + closer to the letter ‘T’”). + + <p style="margin-bottom: -2em;"> + Mom’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="#numericargument">numeric argument</a>. + Groff’s escapes begin with the backslash + character but typically have no star and are in lower case. For + example, the mom escapes to move forward 6 + points on a line are either + + <span class="pre" style="margin-bottom: -2em;"> + \*[FP6] or \*[FWD 6p] + </span> + + while the groff escape for the same thing is + + <span class="pre" style="margin-bottom: -2em;"> + \h’6p’ + </span> + </p> + + </dd> + + <dt id="inputline" style="margin-top: -1em;">Input line</dt> + <dd> + A line of text as it appears in your text editor. + </dd> + + <dt id="macros">Macros</dt> + <dd> + Instructions embedded in a document that determine how groff + processes the text for output. mom’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="#primitives">primitives</a>. + </dd> + + <dt id="units">Machine units</dt> + <dd> + A machine unit is 1/1000 of a + <a href="#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 + mom was originally designed.) + </dd> + + <dt id="numericargument">Numeric argument</dt> + <dd> + An + <a href="#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="#unitofmeasure">unit of measure</a>, + a unit of measure must be appended to <em>every</em> digit in + the argument. For example: + + <span class="pre" style="margin-bottom: -2em;"> + .ALD 1i-1v + </span> + + <div class="box-important" style="margin-right: 2.5em;"> + <p class="tip"> + <span class="important">IMPORTANT:</span> 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 mom’s macros is slim. + </p> + </div> + </dd> + + <dt id="outputline">Output line</dt> + <dd> + A line of text as it appears in output copy. + </dd> + + <dt id="preprocessor">Pre-processor</dt> + <dd> + Pre-processors are used by groff to generate tables + (<strong>tbl</strong>), diagrams (<strong>pic</strong>), graphs + (<strong>grap</strong>), and equations (<strong>eqn</strong>). + These pre-processors are fully supported by mom. In addition, + the “refer” pre-processor is used to generate + bibliographies and lists of cited works. The PDF_IMAGE macro, + which allows insertion of graphics into a document, is not + strictly a pre-processor but behaves similarly to tbl, pic, and + eqn. + </dd> + + <dt id="primitives">Primitives</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 id="stringargument">String Argument</dt> + <dd> + Technically, any + <a href="#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="#macros">macro</a> + + <span class="pre" style="margin-bottom: -2em;"> + .TITLE "My Pulitzer Novel" + </span> + + <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="#inlines">inline escapes</a> + <kbd>\(lq</kbd> and <kbd>\(rq</kbd> (leftquote and + rightquote respectively) in place of the double-quote character + (<kbd>"</kbd>). + </p> + + </dd> + + <dt id="unitofmeasure">Unit of measure</dt> + <dd> + The single letter after a + <a href="#numericargument">numeric argument</a> + that tells mom what measurement scale the + argument should use. Common valid units are: + + <span class="pre" style="margin-bottom: -2em;"> + i (inches) + p (points) + P (Picas) + c (centimetres) + m (ems) + n (ens) + u (machine units) + v (the current leading [line space]) + </span> + + <p style="margin-top: -1em;"> + 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: + + <span class="pre" style="margin-bottom: -2em;"> + .ALD 2v + .LL 39P + .IL 1i + </span> + + The above example advances 2 line spaces and sets the line + length to 39 picas with a left indent of 1 inch. + </p> + + <div class="box-important" style="margin-right: 2.5em;"> + <p class="tip"> + <span class="important">IMPORTANT:</span> + Most mom macros that set the size or measure of something must + be given a unit of measure since most of the macros do not have + default units of measure. There are a couple of exceptions, + the most notable of which are <kbd>PT_SIZE</kbd> and + <kbd class="bold">LS</kbd>. Both use + <a href="#picaspoints">points</a> + as the default unit of measure, which means you don’t have to + append “p” to their argument. + </p> + </div> + + <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> + + <div class="box-tip" style="margin-right: 2.5em;"> + <p class="tip"> + <span class="note">Note:</span> + 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> + </div> + + </dd> + + <dt id="zerowidthcharacter">Zero-width character</dt> + <dd> + The + <a href="#inlines">inline escape</a> + that allows you to print a literal period, apostrophe and, if + <a href="#outputline">output lines</a> + are + <a href="#filled">filled</a>, + a space that falls at the beginning of an + <a href="#inputline">input line</a>. + It looks like this: + + <span class="pre" style="margin-bottom: -2em;"> + \& <span style="font-family: arial, sans-serif; font-weight: normal">(i.e. a backslash followed by an ampersand)</span> + </span> + + Normally, groff interprets a period (or an apostrophe) at the + beginning of an input line as meaning that what follows is a + <a href="#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. + to 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> + +<h3 id="mom-terms" class="docs">Mom terms</h3> +<dl> + <dt id="baseline-grid">Baseline grid</dt> + <dd> + Virtual guide lines spaced according to the + <a href="#leading">leading</a> + established for running text. Adherence to the grid ensures that + text fills the page completely to the bottom margin. Uncorrected + deviations from the grid result in bottom margins that fall short. + </dd> + + <dt id="controlmacro">Control macro</dt> + <dd> + Macros used in + <a href="docprocessing.html#docprocessing">document processing</a> + to control/alter the appearance of document elements (e.g. + headings, quotes, footnotes, + <a href="#header">headers</a>, + etc.). + </dd> + + <dt id="docheader">Document header/docheader</dt> + <dd> + Document information (title, subtitle, author, etc) output at + the top of page one. + </dd> + + <dt id="epigraph">Epigraph</dt> + <dd> + A short, usually cited passage that appears at the beginning of + a chapter, story, or other document. + </dd> + + <dt id="float">Float</dt> + <dd> + A float is material intended to be kept together as a block. + Floated material that fits on a page in position is output on that + page. Floats that do not fit in position are deferred to the top + of the next page. + </dd> + + <dt id="footer">Footer/page footer</dt> + <dd> + Document information (frequently author and title) output in + the bottom margin of pages after page one. Not to be + confused with footnotes, which are considered part of + <a href="#running">running text</a>. + </dd> + + <dt id="head">Heading</dt> + <dd> + The title used to identify a section of a document. Headings + are hierarchic, corresponding to the notion of head, subhead, + subsubhead, etc. + </dd> + + <dt id="header">Header/page header</dt> + <dd> + Document information (frequently author and title) output in the + top margin of pages after page one. + + <div class="box-tip" style="margin-right: 2.5em;"> + <p class="tip"> + <span class="note">Note:</span> In terms of content and style, + headers and + <a href="#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> + </div> + + </dd> + + <dt id="linebreak">Linebreak/author linebreak</dt> + <dd> + A gap in the vertical flow of + <a href="#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 id="parahead">Paragraph head</dt> + <dd> + A heading joined to the body of a paragraph. + </dd> + + <dt id="pdflink">PDF link</dt> + <dd> + A portion of text that, when clicked on in a PDF viewer, + navigates to a bookmarked location in a document, generally but not + exclusively a heading. PDF links are usually coloured to make + them stand out from the surrounding text. + </dd> + + <dt id="pdfoutline">PDF outline</dt> + <dd> + The hierarchically-arranged navigation outline provided by most PDF + viewers (e.g. Okular, Evince), typically in a panel to the left of + the document window, and usually labelled “Contents”. + </dd> + + <dt id="quote">Quote</dt> + <dd> + A quote, to mom, 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"><kbd>BR</kbd></a> + with quotes. + </dd> + + <dt id="running">Running text</dt> + <dd> + In a document formatted with mom, running + text means text that forms the body of the document, including + elements such as headings. + <a href="#docheader">Docheaders</a>, + <a href="#header">headers</a>, + <a href="#footer">footers</a> + and page numbers are not part of running text. + </dd> + + <dt id="toggle">Toggle</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> + +<div class="rule-long"><hr/></div> + +<!-- Navigation links --> +<table style="width: 100%;"> + <tr> + <td style="width: 33%;"><a href="toc.html">Back to Table of Contents</a></td> + <td style="width: 33%; text-align: center;"><a href="#top">Top</a></td> + <td style="width: 33%; text-align: right;"><a href="using.html#top">Next: Using mom</a></td> +</tr> +</table> + +</div> + +<div class="bottom-spacer"><br/></div> + +</body> +</html> |