Annotation of mandoc/roff.7, Revision 1.7
1.7 ! schwarze 1: .\" $Id: roff.7,v 1.6 2010/05/24 22:25:58 schwarze Exp $
1.1 kristaps 2: .\"
3: .\" Copyright (c) 2010 Kristaps Dzonsons <kristaps@bsd.lv>
4: .\"
5: .\" Permission to use, copy, modify, and distribute this software for any
6: .\" purpose with or without fee is hereby granted, provided that the above
7: .\" copyright notice and this permission notice appear in all copies.
8: .\"
9: .\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10: .\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11: .\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12: .\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13: .\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14: .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15: .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16: .\"
1.7 ! schwarze 17: .Dd $Mdocdate: May 24 2010 $
1.1 kristaps 18: .Dt ROFF 7
19: .Os
20: .Sh NAME
21: .Nm roff
22: .Nd roff language reference
23: .Sh DESCRIPTION
24: The
25: .Nm roff
26: language is a general-purpose text-formatting language. The purpose of
27: this document is to consistently describe those language constructs
28: accepted by the
29: .Xr mandoc 1
30: utility. It is a work in progress.
31: .Pp
32: An
33: .Nm
34: document follows simple rules: lines beginning with the control
35: characters
36: .Sq \.
37: or
38: .Sq \(aq
39: are parsed for macros. Other lines are interpreted within the scope of
40: prior macros:
41: .Bd -literal -offset indent
42: \&.xx Macro lines change control state.
43: Other lines are interpreted within the current state.
44: .Ed
45: .Sh LANGUAGE SYNTAX
46: .Nm
47: documents may contain only graphable 7-bit ASCII characters, the space
48: character, and, in certain circumstances, the tab character. All
49: manuals must have
50: .Ux
51: line terminators.
52: .Sh MACRO SYNTAX
53: Macros are arbitrary in length and begin with a control character ,
54: .Sq \.
55: or
56: .Sq \(aq ,
57: at the beginning of the line.
58: An arbitrary amount of whitespace may sit between the control character
59: and the macro name.
60: Thus, the following are equivalent:
61: .Bd -literal -offset indent
62: \&.if
63: \&.\ \ \ \&if
64: .Ed
65: .Sh REFERENCE
66: This section is a canonical reference of all macros, arranged
67: alphabetically.
1.3 kristaps 68: .Ss \&am
69: The syntax of this macro is the same as that of
70: .Sx \&ig ,
71: except that a leading argument must be specified.
72: It is ignored, as are its children.
73: .Ss \&ami
74: The syntax of this macro is the same as that of
75: .Sx \&ig ,
76: except that a leading argument must be specified.
77: It is ignored, as are its children.
78: .Ss \&am1
79: The syntax of this macro is the same as that of
80: .Sx \&ig ,
81: except that a leading argument must be specified.
82: It is ignored, as are its children.
83: .Ss \&de
84: The syntax of this macro is the same as that of
85: .Sx \&ig ,
86: except that a leading argument must be specified.
87: It is ignored, as are its children.
88: .Ss \&dei
89: The syntax of this macro is the same as that of
90: .Sx \&ig ,
91: except that a leading argument must be specified.
92: It is ignored, as are its children.
1.6 schwarze 93: .Ss \&ds
94: Define a string.
95: This macro is intended to have two arguments,
96: the name of the string to define and its content.
97: Currently, it is ignored including its arguments,
98: and the number of arguments is not checked.
1.3 kristaps 99: .Ss \&de1
100: The syntax of this macro is the same as that of
101: .Sx \&ig ,
102: except that a leading argument must be specified.
103: It is ignored, as are its children.
1.5 kristaps 104: .Ss \&el
105: The
106: .Qq else
107: half of an if/else conditional.
108: Pops a result off the stack of conditional evaluations pushed by
109: .Sx \&ie
110: and uses it as its conditional.
111: If no stack entries are present (e.g., due to no prior
112: .Sx \&ie
113: calls)
114: then false is assumed.
115: The syntax of this macro is similar to
116: .Sx \&if
117: except that the conditional is missing.
118: .Ss \&ie
119: The
120: .Qq if
121: half of an if/else conditional.
122: The result of the conditional is pushed into a stack used by subsequent
123: invocations of
124: .Sx \&el ,
125: which may be separated by any intervening input (or not exist at all).
126: Its syntax is equivalent to
127: .Sx \&if .
1.1 kristaps 128: .Ss \&if
1.7 ! schwarze 129: Begins a conditional.
! 130: Right now, the conditional evaluates to true
! 131: if and only if it starts with the letter
! 132: .Sy n ,
! 133: indicating processing in
! 134: .Xr nroff 1
! 135: style as opposed to
! 136: .Xr troff 1
! 137: style.
1.3 kristaps 138: If a conditional is false, its children are not processed, but are
139: syntactically interpreted to preserve the integrity of the input
140: document.
141: Thus,
142: .Pp
143: .D1 \&.if t \e .ig
144: .Pp
145: will discard the
146: .Sq \&.ig ,
147: which may lead to interesting results, but
148: .Pp
149: .D1 \&.if t \e .if t \e{\e
150: .Pp
151: will continue to syntactically interpret to the block close of the final
152: conditional.
153: Sub-conditionals, in this case, obviously inherit the truth value of
154: the parent.
155: This macro has the following syntax:
1.1 kristaps 156: .Pp
157: .Bd -literal -offset indent -compact
158: \&.if COND \e{\e
159: BODY...
160: \&.\e}
161: .Ed
162: .Bd -literal -offset indent -compact
163: \&.if COND \e{ BODY
1.2 kristaps 164: BODY... \e}
165: .Ed
166: .Bd -literal -offset indent -compact
167: \&.if COND \e{ BODY
1.1 kristaps 168: BODY...
169: \&.\e}
170: .Ed
171: .Bd -literal -offset indent -compact
172: \&.if COND \e
173: BODY
174: .Ed
175: .Pp
1.3 kristaps 176: COND is a conditional (for the time being, this always evaluates to
177: false).
1.1 kristaps 178: .Pp
179: If the BODY section is begun by an escaped brace
180: .Sq \e{ ,
181: scope continues until a closing-brace macro
182: .Sq \.\e} .
183: If the BODY is not enclosed in braces, scope continues until the next
184: macro or word.
185: If the COND is followed by a BODY on the same line, whether after a
186: brace or not, then macros
187: .Em must
188: begin with a control character.
189: It is generally more intuitive, in this case, to write
190: .Bd -literal -offset indent
191: \&.if COND \e{\e
192: \&.foo
193: bar
194: \&.\e}
195: .Ed
196: .Pp
197: than having the macro follow as
198: .Pp
199: .D1 \&.if COND \e{ .foo
200: .Pp
201: The scope of a conditional is always parsed, but only executed if the
202: conditional evaluates to true.
203: .Pp
204: Note that text subsequent a
1.2 kristaps 205: .Sq \&.\e}
206: macro is discarded.
207: Furthermore, if an explicit closing sequence
1.1 kristaps 208: .Sq \e}
1.2 kristaps 209: is specified in a free-form line, the entire line is accepted within the
210: scope of the prior macro, not only the text preceding the close.
1.1 kristaps 211: .Ss \&ig
1.2 kristaps 212: Ignore input.
213: Accepts the following syntax:
214: .Pp
215: .Bd -literal -offset indent -compact
216: \&.ig
217: BODY...
218: \&..
219: .Ed
220: .Bd -literal -offset indent -compact
221: \&.ig END
222: BODY...
223: \&.END
224: .Ed
225: .Pp
226: In the first case, input is ignored until a
227: .Sq \&..
1.1 kristaps 228: macro is encountered on its own line.
1.2 kristaps 229: In the second case, input is ignored until a
230: .Sq \&.END
231: is encountered.
232: Text subsequent the
233: .Sq \&.END
234: or
235: .Sq \&..
1.1 kristaps 236: is discarded.
1.2 kristaps 237: .Pp
238: Do not use the escape
239: .Sq \e
240: anywhere in the definition of END.
241: It causes very strange behaviour.
242: Furthermore, if you redefine a
243: .Nm
244: macro, such as
245: .Pp
246: .D1 \&.ig if
247: .Pp
248: the subsequent invocation of
249: .Sx \&if
250: will first signify the end of comment, then be invoked as a macro.
251: This behaviour really shouldn't be counted upon.
1.6 schwarze 252: .Ss \&rm
253: Remove a request, macro or string.
254: This macro is intended to have one argument,
255: the name of the request, macro or string to be undefined.
256: Currently, it is ignored including its arguments,
257: and the number of arguments is not checked.
258: .Ss \&tr
259: Output character translation.
1.7 ! schwarze 260: This macro is intended to have one argument,
1.6 schwarze 261: consisting of an even number of characters.
262: Currently, it is ignored including its arguments,
263: and the number of arguments is not checked.
1.2 kristaps 264: .Sh COMPATIBILITY
265: This section documents compatibility between mandoc and other other
266: troff implementations, at this time limited to GNU troff
267: .Pq Qq groff .
268: The term
269: .Qq historic groff
270: refers to groff versions before the
271: .Pa doc.tmac
272: file re-write
273: .Pq somewhere between 1.15 and 1.19 .
274: .Pp
275: .Bl -dash -compact
276: .It
277: Historic groff did not accept white-space buffering the custom END tag
278: for the
279: .Sx \&ig
280: macro.
1.4 kristaps 281: .It
282: The
283: .Sx \&if
284: and family would print funny white-spaces with historic groff when
285: depending on next-line syntax.
1.2 kristaps 286: .El
1.1 kristaps 287: .Sh AUTHORS
288: The
289: .Nm
290: reference was written by
291: .An Kristaps Dzonsons Aq kristaps@bsd.lv .
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