Re: [Boost-users] boost::function unusable as overloadable function argument

AMDG Peter Soetens wrote:

I had this situation in a bigger program, where a user could supply a string or a function object:

<code> #include #include <string>

void foo1(int i, std::string a); void foo1(int i, boost::function foo );

int main(int argc, char** argv) { //boost::function foo = "hello"; // this line won't compile

foo1( 3, "hello" ); //error: call of overloaded ‘foo1(int, const char [6])’ is ambiguous

return 0; } </code>

Although constructing a boost::function from a C string is nonsense, the compiler does consider it as an alternative when trying to find the right foo1. Is there any work around to keep the overloads without requiring the user to write foo1(3, string("hello")); or is this a compiler bug (g++ (Ubuntu 4.3.3-5ubuntu4) 4.3.3)?

You can use tag dispatching: void foo1_impl(int, std::string a, boost::mpl::true_); void foo1_impl(int, boost::function, boost::mpl::false_); template<class T> void foo1(int i, T t) { foo1_impl(i, t, boost::is_convertible()); }; In Christ, Steven Watanabe