Add R_class function.

git-svn-id: https://svn.r-project.org/R/trunk@89095 00db46b3-68df-0310-9c12-caf00c1e9a41

Author: luke

doc/NEWS.Rd

@@ -233,16 +233,20 @@
       \code{SET_FORMALS}, \code{SET_BODY}, \code{SET_CLOENV},
       \code{STRING_PTR}, \code{DATAPTR}, \code{XTRUELENGTH},
       \code{R_duplicate_attr}, \code{R_shallow_duplicate_attr},
-      \code{getConnection}, \code{LEVELS}, \code{SETLEVELS}.
+      \code{getConnection}, \code{LEVELS}, \code{SETLEVELS},
+      \code{R_data_class}.
 
       \item The deprecated macros \code{CHARACTER_DATA} and
       \code{CHARACTER_POINTER} now return \code{const} pointers since using
       writable pointers in packages is not safe.
 
-      \item New function \code{DATAPTR_RW} for use in implementing
+      \item New function \code{DATAPTR_RW()} for use in implementing
       \code{ALTREP} \code{Dataptr} methods. This function should not be
       used in any other contexts.
 
+      \item New function \code{R_class()} as the \code{C} equivalent of
+      \code{class()} in \R.
+
       \item The non-API header files \file{R_ext/Callbacks.h} and
       \file{R_ext/PrtUtil.h} are no longer copied to the installed
       includes directory.

doc/manual/R-exts.texi

@@ -13022,6 +13022,11 @@ As the value is a character vector, we have to know how to create that
 from a C character array, which we do using the function
 @code{Rf_mkChar}.
 
+Objects without an explicit class can have an implicit class. In @R{}
+the function @code{class} returns the explicit or implicit class. The
+function @code{R_class} is the @code{C} equivalent.
+@apifun R_class
+
 @node S4 objects
 @subsection S4 objects
 @cindex S4 objects
@@ -17602,6 +17607,8 @@ functions that should be used instead:
       an argument to your C function.
 @item SETLENGTH
       See @ref{Resizing vectors}.
+@item R_data_class
+      Use @code{R_class} added in @R{} 4.6.0
 @end table
 
 For recently added entry points packages that need to be compiled
@@ -17810,6 +17817,7 @@ void CLEAR_ATTRIB(SEXP x)
 
 #if R_VERSION < R_Version(4, 6, 0)
 # define DATAPTR_RW(x) DATAPTR(x)
+# define R_class(x) R_data_class(x, FALSE)
 # define R_allocResizableVector(type, maxlen) Rf_allocVector(type, naxlen)
 # define R_duplicateAsResizable(x) duplicate(x)
 # define R_resizeVector(x, newlen) SETLENGTH(x, n)

src/include/Rinternals.h

@@ -512,6 +512,7 @@ SEXP Rf_allocSExp(SEXPTYPE);
 //SEXP Rf_allocVector3(SEXPTYPE, R_xlen_t, R_allocator_t*);
 R_xlen_t Rf_any_duplicated(SEXP x, Rboolean from_last); // unique.c
 R_xlen_t Rf_any_duplicated3(SEXP x, SEXP incomp, Rboolean from_last); // unique.c
+SEXP R_class(SEXP);
 SEXP Rf_classgets(SEXP, SEXP);
 SEXP Rf_cons(SEXP, SEXP);
 void Rf_copyMatrix(SEXP, SEXP, Rboolean); // duplicate.c

src/library/tools/R/sotools.R

@@ -747,7 +747,7 @@ warnNonAPI <-
       "OBJECT", "SET_TYPEOF", "ENVFLAGS", "SET_ENVFLAGS", "SET_FORMALS",
       "SET_BODY", "SET_CLOENV", "STRING_PTR", "DATAPTR", "XTRUELENGTH",
       "R_shallow_duplicate_attr", "R_duplicate_attr", "getConnection",
-      "LEVELS", "SETLEVELS")
+      "LEVELS", "SETLEVELS", "R_data_class")
 
 ## grDevices uses R_Home R_InputHandlers R_TempDir R_Visible R_cairoCdynload R_fopen R_gzclose R_gzgets R_gzopen R_isForkedChild Rf_envlength Rf_strIsASCII Rf_utf8towcs Rg_set_col_ptrs Ri18n_wcwidth addInputHandler do_X11 do_contourLines do_getGraphicsEventEnv do_getSnapshot do_playSnapshot do_saveplot locale2charset mbcsToUcs2 ptr_R_ProcessEvents
 

src/main/attrib.c

@@ -908,6 +908,9 @@ attribute_hidden SEXP R_do_data_class(SEXP call, SEXP op, SEXP args, SEXP env)
   return R_data_class(CAR(args), FALSE);
 }
 
+// C version of class()
+SEXP R_class(SEXP x) { return R_data_class(x, FALSE); }
+
 /* names(object) <- name */
 attribute_hidden SEXP do_namesgets(SEXP call, SEXP op, SEXP args, SEXP env)
 {