[Rcpp-commits] r302 - in pkg/src: . Rcpp

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

Author: romain
Date: 2010-01-07 16:27:21 +0100 (Thu, 07 Jan 2010)
New Revision: 302

Modified:
   pkg/src/Promise.cpp
   pkg/src/Rcpp/Promise.h
Log:
minor update of Promise

Modified: pkg/src/Promise.cpp
===================================================================
--- pkg/src/Promise.cpp	2010-01-07 15:16:32 UTC (rev 301)
+++ pkg/src/Promise.cpp	2010-01-07 15:27:21 UTC (rev 302)
@@ -27,6 +27,10 @@
 
 namespace Rcpp {
 
+	const char* Promise::unevaluated_promise::what() throw() {
+		return "promise not yet evaluated" ;
+	}
+	
 	Promise::Promise(SEXP x) throw(not_compatible) : RObject(){
 		if( TYPEOF(x) == PROMSXP ){
 			setSEXP( x ) ;
@@ -35,13 +39,19 @@
 		}
 	}
 
-	int Promise::seen(){
+	int Promise::seen() const {
 		return PRSEEN(m_sexp);
 	}
 
-	RObject Promise::value() const{
-		return wrap( PRVALUE(m_sexp) ) ;
+	RObject Promise::value() const throw(unevaluated_promise) {
+		SEXP val = PRVALUE(m_sexp) ; 
+		if( val == R_UnboundValue ) throw unevaluated_promise() ;
+		return wrap( val ) ;
 	}
+	
+	bool Promise::was_evaluated() const {
+		return PRVALUE(m_sexp) != R_UnboundValue ;
+	}
 
 	Environment Promise::environment() const {
 		return Environment(PRENV(m_sexp)) ;

Modified: pkg/src/Rcpp/Promise.h
===================================================================
--- pkg/src/Rcpp/Promise.h	2010-01-07 15:16:32 UTC (rev 301)
+++ pkg/src/Rcpp/Promise.h	2010-01-07 15:27:21 UTC (rev 302)
@@ -32,18 +32,28 @@
 
 class Promise : public RObject {     
 public:
+
+	class unevaluated_promise : public std::exception{
+	public:
+		unevaluated_promise() throw(){}; 
+		~unevaluated_promise() throw(){} ;
+		const char* what() throw() ;
+	} ;
+
 	Promise( SEXP x) throw(not_compatible) ;
 	
 	/** 
 	 * Return the result of the PRSEEN macro
 	 */
-	int seen() ;
+	int seen() const ;
 	
 	/**
 	 * Return the result of the PRVALUE macro on the promise
 	 */
-	RObject value() const ;
+	RObject value() const throw(unevaluated_promise) ;
 
+	bool was_evaluated() const ;
+	
 	/**
 	 * The promise expression: PRCODE
 	 */