     Syntax: bf(%baseclass-preinclude) tt(pathname)nl()
           tt(Pathname) defines the path to the file preincluded in the
            parser's base-class header.  See the description of the
            link(--baseclass-preinclude)(PREINCLUDE) option for details about
            this directive. By default `filename' is surrounded by double
            quotes; it's OK, however, to provide them yourself.  When the
            argument is surrounded by em(pointed brackets) tt(#include
            <header>) is used.
