spac-lin.mkxl /size: 5736 b    last modification: 2023-12-21 09:44
1%D \module
2%D   [       file=spac-lin,
3%D        version=2012.01.08, % 2009.10.16 (core-ver) 1997.03.31 (core-spa)
4%D          title=\CONTEXT\ Spacing Macros,
5%D       subtitle=Vertical,
6%D         author=Hans Hagen,
7%D           date=\currentdate,
8%D      copyright={PRAGMA ADE \& \CONTEXT\ Development Team}]
9%C
10%C This module is part of the \CONTEXT\ macro||package and is
11%C therefore copyrighted by \PRAGMA. See mreadme.pdf for
12%C details.
13
14\writestatus{loading}{ConTeXt Spacing Macros / Lines}
15
16\unprotect
17
18%D When spacing is active we need to handle commands in a special way:
19%D
20%D \starttyping
21%D \setuplines[space=on]
22%D
23%D \startlines
24%D Let's talk about this{\ttsl\gobbleoneargument or}that.
25%D \stoplines
26%D
27%D \startlines
28%D Let's talk about this{\getvalue{ttsl}or}that.
29%D \stoplines
30%D \stoptyping
31%D
32%D One can indent in several ways:
33%D
34%D \starttyping
35%D \setupindenting[medium] \setuplines[indenting=odd] % no yes odd even
36%D
37%D \startlines
38%D first
39%D second
40%D third
41%D fourth
42%D \stoplines
43%D \stoptyping
44
45%D Contrary to \MKII\ we can now define classes of lines (generalized by
46%D Wolfgang). I will probably rewrite bits in \LUA.
47
48\installcorenamespace{lines}
49
50\installcommandhandler \??lines {lines} \??lines
51
52\setuplines
53  [\c!option=,
54   \c!command=,
55   \c!before=\blank,
56   \c!after=\blank,
57   \c!inbetween=\blank,
58   \c!indenting=\v!no,
59   \c!space=\v!default]
60
61\appendtoks
62   \frozen\instance\protected\edefcsname\e!start\currentlines\endcsname{\spac_lines_start[\currentlines]}%
63   \frozen\instance\letcsname           \e!stop \currentlines\endcsname \spac_lines_stop
64\to \everydefinelines
65
66\lettonothing\p_lines_option
67
68\let\spac_lines_break            \relax
69\let\spac_after_first_obeyed_line\relax
70\let\spac_lines_indent           \relax
71
72%D See \type {indentation-005.tex}:
73%D
74%D \starttyping
75%D \setuplines[indentlist={0pt,10pt,15pt,20pt}]
76%D
77%D \setupindenting[yes,1em]
78%D \setuplines[indentlist={0pt,*,*}]
79%D
80%D \setuplines[indentlist={0pt,1em,*}]
81%D \starttyping
82
83\newinteger  \c_spac_lines_indent_cnt
84\newinteger  \c_spac_lines_indent_max
85\newdimension\d_spac_lines_indent
86
87\def\spac_lines_indent_indeed
88  {\ifnum\c_spac_lines_indent_cnt=\c_spac_lines_indent_max
89     \c_spac_lines_indent_cnt\plusone
90   \else
91     \advanceby\c_spac_lines_indent_cnt\plusone
92   \fi
93   \getfromcommacommand[\m_spac_lines_indentlist][\c_spac_lines_indent_cnt]%
94   \ifx\commalistelement\wildcardsymbol
95     \hskip\d_spac_lines_indent
96   \else
97     \scratchdimen\dimexpr\commalistelement\relax
98     \hskip
99       \ifzeropt\scratchdimen
100         \zeropoint
101       \else
102         \scratchdimen
103         \d_spac_lines_indent\scratchdimen
104       \fi
105   \fi
106   \relax}
107
108\permanent\tolerant\protected\def\spac_lines_start[#1]%
109  {\bgroup
110   \cdef\currentlines{#1}%
111   \obeylines
112   \spac_lines_start_indeed}
113
114\tolerant\def\spac_lines_start_indeed[#S#1]% new: optional second argument (WS)
115  {\ifarguments\or
116     \setupcurrentlines[#1]%
117   \fi
118   \edef\p_lines_option{\linesparameter\c!option}%
119   \ifx\p_lines_option\v!packed
120     \let\spac_lines_break\nobreak
121   \else
122     \let\spac_lines_break\relax
123   \fi
124   \linesparameter\c!before
125   \push_macro_checkindentation
126   \whitespace
127   \dostarttaggedchained\t!lines\currentlines\??lines
128   \begingroup
129   \uselinesstyleandcolor\c!style\c!color
130   \useindentingparameter\linesparameter
131   \usealignparameter\linesparameter
132   \typesettinglinestrue
133   \setupwhitespace[\v!none]% todo use fast variant
134   %\obeylines % move upwards to keep spaces in the first line due to optional argument
135   %
136   \edef\m_spac_lines_indentlist{\linesparameter\c!indentlist}%
137   \getcommacommandsize[\m_spac_lines_indentlist]%
138   \c_spac_lines_indent_max\commalistsize
139   \c_spac_lines_indent_cnt\zerocount
140   \ifnum\c_spac_lines_indent_max>\plusone
141     \let\spac_lines_indent\spac_lines_indent_indeed
142     \d_spac_lines_indent\d_spac_indentation_par
143   \else
144     \let\spac_lines_indent\relax
145   \fi
146   %
147   \ignorespaces
148   \glet\spac_after_first_obeyed_line\spac_lines_after_first_obeyed_line_a
149   \enforced\let\obeyedline\spac_lines_obeyed_line
150   \activatespacehandler{\linesparameter\c!space}%
151   \dostarttagged\t!line\empty
152   \ignorepars}
153
154
155% we could have states instead and handle option in there
156
157\def\spac_lines_after_first_obeyed_line_a % tzt two pass, like itemize
158  {\linesparameter\c!command
159   \spac_lines_indent
160   \linesparameter\c!left
161   \glet\spac_after_first_obeyed_line\spac_lines_after_first_obeyed_line_b}
162
163\def\spac_lines_after_first_obeyed_line_b
164  {\spac_lines_break
165   \linesparameter\c!command
166   \spac_lines_indent
167   \linesparameter\c!left}
168
169\def\spac_lines_obeyed_line
170  {\ifdone\linesparameter\c!right\fi
171   \dostoptagged % can be a dummy one as we don't look ahead
172   \par
173   \dostarttagged\t!line\empty
174   \futurelet\nexttoken\spac_lines_between}
175
176\protected\def\spac_lines_stop
177  {\dostoptagged
178   \endgroup
179   \dostoptagged
180   \pop_macro_checkindentation
181   \linesparameter\c!after
182   \egroup}
183
184\def\spac_lines_between
185  {\ifx\nexttoken\spac_lines_stop
186     \donefalse
187   \else
188     \doifelsemeaning\nexttoken\obeyedline % brrr
189       {\donefalse\linesparameter\c!inbetween}
190       {\donetrue\spac_after_first_obeyed_line}%
191   \fi}
192
193\definelines[\v!lines]
194
195\permanent\tolerant\protected\def\emptylines[#1]%
196  {\endgraf
197   \begingroup
198  %\forgetall % debatable
199   \ifhmode
200      \crlf % finish the current line
201   \fi
202   \scratchcounter\ifparameter#1\or#1\else3\fi\relax
203   \dorecurse\scratchcounter{\strut\crlf}%
204   \endgroup}
205
206\ifdefined\startlines \else
207    \aliased\expandafter\let\expandafter\startlines\csname\e!start\v!lines\endcsname
208    \aliased\expandafter\let\expandafter\stoplines \csname\e!stop \v!lines\endcsname
209\fi
210
211\protect \endinput
212