:
: add entry to the list of exported symbols (unless e or m);
: any doc entry goes in perlapi.pod rather than perlintern.pod. If
-: none specified, autodoc.pl does not list this function/macro as
-: part of the public API. If x isn't specified, and no
-: documentation is furnished, autodoc.pl lists this in perlapi as
-: existing and being undocumented.
+: no documentation is furnished, x controls what happens: If x
+: isn't specified, autodoc.pl lists this in perlapi as existing and
+: being undocumented; otherwise it simply isn't listed.
: makes '#define foo Perl_foo' scope not just for PERL_CORE/PERL_EXT
:
: If the function is only exported for use in a public macro, see X.