don't load sourceCpp dynamic library if it's already been loaded

Author: jjallaire

ChangeLog

@@ -1,3 +1,8 @@
+2015-06-07  JJ Allaire <[email protected]>
+
+        * src/attributes.cpp: Don't load sourceCpp dynamic library if it's
+        already been loaded
+
 2015-06-05  Dirk Eddelbuettel  <[email protected]>
 
         * R/Rcpp.package.skeleton.R (Rcpp.package.skeleton): Remove

inst/NEWS.Rd

@@ -8,6 +8,11 @@
     \itemize{
       \item The sugar function \code{sapply} now supports lambda functions
     }
+    \item Changes in Rcpp Attributes:
+    \itemize{
+      \item Don't load \code{sourceCpp} dynamic library if it's already 
+      been loaded.
+    }
     \item Changes in Rcpp Documentation:
     \itemize{
       \item The \code{Rcpp-FAQ} vignette was once again updated with respect to

src/attributes.cpp

@@ -2877,17 +2877,15 @@ namespace {
                 throw Rcpp::file_io_error(generatedRSourcePath());
 
             // DLLInfo - hide using . and ensure uniqueness using contextId
-            std::string dllInfo = "`." + contextId_ + "_DLLInfo`";
-            rOfs << dllInfo << " <- dyn.load('" << dynlibPath() << "')"
+            std::string dllInfoName = "." + contextId_ + "_DLLInfo";
+            std::string dllInfo = "`" + dllInfoName + "`";
+            rOfs << "if (!exists('" << dllInfoName << "', inherits = FALSE))" << std::endl;
+            rOfs << "   " << dllInfo << " <- dyn.load('" << dynlibPath() << "')"
                  << std::endl << std::endl;
 
             // Generate R functions
             generateR(rOfs, sourceAttributes, dllInfo);
 
-            // remove the DLLInfo
-            rOfs << std::endl << "rm(" << dllInfo << ")"
-                 << std::endl;
-
             rOfs.close();
 
             // discover exported functions and dependencies