does not recognize anchors that are already in a file when it opens
the file.
Tips
You can change anchor names as often as you want by specifying
the ANCHOR= option in a markup family statement anywhere in
your program. After you have specified an anchor name, it
remains in effect until you specify a new one.
Specifying new anchor names at various points in your program
is useful when you want other web pages to link to specific parts
of your markup language output. Because you can control where
the anchor name changes, you know in advance what the anchor
name is at those points.
An anchor-name must begin with a letter ([A-Za-z]) and can be
followed ...
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