From dfd3da2cc461a6c77d80074b6088e9b0eed459a2 Mon Sep 17 00:00:00 2001 From: Peter Dimov Date: Tue, 19 Feb 2008 15:40:58 +0000 Subject: [PATCH] Fix #1643. [SVN r43323] --- bind.html | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/bind.html b/bind.html index f60cab0..74110c5 100644 --- a/bind.html +++ b/bind.html @@ -60,6 +60,7 @@

Inappropriate use of bind<R>(f, ...)

Binding a nonstandard function

+

Binding an overloaded function

const in signatures

MSVC specific: using boost::bind;

@@ -553,6 +554,37 @@ int main() recognized by the short form of bind.

See also "__stdcall" and "pascal" Support.

+

Binding an overloaded function

+

An attempt to bind an overloaded function usually results in an error, as there + is no way to tell which overload was meant to be bound. This is a common + problem with member functions with two overloads, const and non-const, as in + this simplified example:

+ 
struct X
+{
+    int& get();
+    int const& get() const;
+};
+
+int main()
+{
+    boost::bind( &X::get, _1 );
+}
+
+

The ambiguity can be resolved manually by casting the (member) function pointer + to the desired type:

+
int main()
+{
+    boost::bind( static_cast< int const& (X::*) () const >( &X::get ), _1 );
+}
+
+

Another, arguably more readable, alternative is to introduce a temporary + variable:

+
int main()
+{
+    int const& (X::*get) () const = &X::get;
+    boost::bind( get, _1 );
+}
+

const in signatures

Some compilers, including MSVC 6.0 and Borland C++ 5.5.1, have problems with the top-level const in function signatures: