diff --git a/mem_fn.html b/mem_fn.html index ed284be..25af8b2 100644 --- a/mem_fn.html +++ b/mem_fn.html @@ -45,7 +45,9 @@ boost::mem_fn is a generalization of the standard functions std::mem_fun and std::mem_fun_ref. It supports member function pointers with more than one argument, and the returned function object can take a pointer, a - reference, or a smart pointer to an object instance as its first argument. + reference, or a smart pointer to an object instance as its first argument. mem_fn + also supports pointers to data members by treating them as functions taking no + arguments and returning a (const) reference to the member.

The purpose of mem_fn is twofold. First, it allows users to invoke a @@ -87,8 +89,8 @@ template<class It, class R, class T> void for_each(It first, It last, R (T documentation of bind for an example.

- mem_fn takes one argument, a pointer to a member function, and returns a - function object suitable for use with standard or user-defined algorithms: + mem_fn takes one argument, a pointer to a member, and returns a function + object suitable for use with standard or user-defined algorithms: 

 struct X
@@ -136,7 +138,8 @@ void k(std::vector<boost::shared_ptr<X> > const & v)
 		

 		

 			All function objects returned by mem_fn expose a result_type typedef 
-			that represents the return type of the member function.
+			that represents the return type of the member function. For data members, result_type
+			is defined as a const reference to the type of the member.
 		

 		
Frequently Asked Questions

 		
Can mem_fn be used instead of the standard std::mem_fun[_ref]
@@ -176,12 +179,14 @@ void k(std::vector<boost::shared_ptr<X> > const & v)
 namespace boost
 {
 
-template<class T> T * get_pointer (T * p);
+template<class T> T * get_pointer(T * p);
 
 template<class R, class T> unspecified-1 mem_fn(R (T::*pmf) ());
 
 template<class R, class T> unspecified-2 mem_fn(R (T::*pmf) () const);
 
+template<class R, class T> unspecified-2-1 mem_fn(R T::*pm);
+
 template<class R, class T, class A1> unspecified-3 mem_fn(R (T::*pmf) (A1));
 
 template<class R, class T, class A1> unspecified-4 mem_fn(R (T::*pmf) (A1) const);
@@ -196,11 +201,12 @@ template<class R, class T, class A1, class A2> unspecified-6 
 		
Common requirements

 		

-			All unspecified-N types mentioned in the Synopsis 
-			are CopyConstructible and Assignable. Their copy constructors and 
-			assignment operators do not throw exceptions. unspecified-N::result_type
-			is defined as the return type of the member function pointer passed as an 
-			argument to mem_fn (R in the Synopsis.)
+			All unspecified-N types mentioned in the Synopsis are CopyConstructible
+			and Assignable. Their copy constructors and assignment operators do not 
+			throw exceptions. unspecified-N::result_type is defined as the 
+			return type of the member function pointer passed as an argument to mem_fn
+			(R in the Synopsis.) unspecified-2-1::result_type is 
+			defined as R const &.
 		

 		
get_pointer

 		
template<class T> T * get_pointer(T * p)

@@ -213,8 +219,8 @@ template<class R, class T, class A1, class A2> unspecified-6 
 		
 		
mem_fn

-		
template<class R, class T> unspecified-1 
-				mem_fn(R (T::*pmf) ())

+		
template<class R, class T> unspecified-1 mem_fn(R 
+				(T::*pmf) ())

 		

 			

 				Returns: a function object f such that the expression f(t)
@@ -225,8 +231,8 @@ template<class R, class T, class A1, class A2> unspecified-6 Throws: Nothing.
 			

 		

-		
template<class R, class T> unspecified-2 
-				mem_fn(R (T::*pmf) () const)

+		
template<class R, class T> unspecified-2 mem_fn(R 
+				(T::*pmf) () const)

 		

 			

 				Returns: a function object f such that the expression f(t)
@@ -238,8 +244,20 @@ template<class R, class T, class A1, class A2> unspecified-6 Throws: Nothing.
 			

 		

-		
template<class R, class T, class A1> unspecified-3
-				mem_fn(R (T::*pmf) (A1))

+		
template<class R, class T> unspecified-2-1 mem_fn(R 
+				T::*pm)

+		

+			

+				Returns: a function object f such that the expression f(t)
+				is equivalent to t.*pm when t is of type T [const]
+					or derived, get_pointer(t)->*pm otherwise.
+			

+			

+				Throws: Nothing.
+			

+		

+		
template<class R, class T, class A1> unspecified-3 mem_fn(R 
+				(T::*pmf) (A1))

 		

 			

 				Returns: a function object f such that the expression f(t, a1)
@@ -250,8 +268,8 @@ template<class R, class T, class A1, class A2> unspecified-6 Throws: Nothing.
 			

 		

-		
template<class R, class T, class A1> unspecified-4
-				mem_fn(R (T::*pmf) (A1) const)

+		
template<class R, class T, class A1> unspecified-4 mem_fn(R 
+				(T::*pmf) (A1) const)

 		

 			

 				Returns: a function object f such that the expression f(t, a1)