|[...]||inherits from \setuphead|
Used to define a new head (such as title, subject etc.). The idea is you can create a MySubject that derives it's defaults from subject and then customize MySubject without being concerned with overriding subject. Use with \setuphead.
The first argument is the name of your new head. The second argument is the name of the head from which yours ought to be derived. The third (optional) argument is for options.
\definehead [Title] [title] \setuphead [Title] [textstyle=bfb, align=middle]
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