[Rd] Rf_protect in Rinternals.h

[Hans-Peter]

Hello!

I'd like to ask you a question about c (macros):

In Rinternals.h are defined:
a)   SEXP Rf_protect(SEXP);
b)   #define protect Rf_protect
c)   #define PROTECT(s)	protect(s)

As far as I understand the calls Rf_protect( x ), protect( x ) and
PROTECT( x ) are all equalent.

So whats the reason that there are 2 macros defined? Why 3 times the
same when 1 distinct function would be enough?

Thanks for some enlightenment...

--
Regards,
Hans-Peter