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1%D \module
2%D   [       file=typo-plc,
3%D        version=2020.07.01,
4%D          title=\CONTEXT\ Typesetting Macros,
5%D       subtitle=Placeholders,
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 Typesetting Macros / Placeholders}
15
16\unprotect
17
18\installcorenamespace {placeholder}
19
20\installcommandhandler \??placeholder {placeholder} \??placeholder
21
22\permanent\tolerant\protected\def\placeholder[#1]%
23  {\begingroup
24   \cdef\currentplaceholder{#1}%
25   \placeholderparameter\c!before
26   \dostarttagged\t!placeholder\currentplaceholder
27   \useplaceholderstyleandcolor\c!style\c!color
28   \ifcstok{\placeholderparameter\c!text}\emptytoks
29     \ifempty{#1}\unknown\else#1\fi
30   \else
31     \lastnamedcs
32   \fi
33   \dostoptagged
34   \placeholderparameter\c!after
35   \endgroup}
36
37\defineplaceholder
38  [todo]
39 %[\c!text={Still to be written!},
40  [\c!text=todo, % labeltext ?
41   \c!style=\v!bold,
42   \c!before=\blank,
43   \c!after=\blank]
44
45\protect \endinput
46