[Rcpp-commits] r2474 - pkg/Rcpp/R

[noreply at r-forge.r-project.org]

Author: jmc
Date: 2010-11-20 19:39:34 +0100 (Sat, 20 Nov 2010)
New Revision: 2474

Modified:
   pkg/Rcpp/R/Module.R
Log:
dont require a default constructor for subclasses of C++ classes

Modified: pkg/Rcpp/R/Module.R
===================================================================
--- pkg/Rcpp/R/Module.R	2010-11-20 18:14:35 UTC (rev 2473)
+++ pkg/Rcpp/R/Module.R	2010-11-20 18:39:34 UTC (rev 2474)
@@ -166,7 +166,16 @@
                                  )
         # just to make codetools happy
         .self <- .refClassDef <- NULL
-        generator$methods(initialize = function(...) Rcpp:::cpp_object_initializer(.self,.refClassDef, ...))
+        generator$methods(initialize =
+              if(cpp_hasDefaultConstructor(CLASS))
+                 function(...) Rcpp:::cpp_object_initializer(.self,.refClassDef, ...)
+              else
+                 function(...) {
+                     if(nargs())  Rcpp:::cpp_object_initializer(.self,.refClassDef, ...)
+                     else .self
+                 }
+                          )
+               
         rm( .self, .refClassDef )
         
         classDef <- getClass(clname)
@@ -259,6 +268,14 @@
     mets
 }
 
+cpp_hasDefaultConstructor <- function(CLASS) {
+    constrs <- CLASS at constructors
+    for(cc in constrs)
+        if(cc$nargs == 0)
+            return(TRUE)
+    FALSE
+}
+
 binding_maker <- function( FIELD, where ){
     f <- function( x ) NULL
     body(f) <- substitute({