Re: Overloading mess: No matching function for call

From:
Pete Becker <pete@versatilecoding.com>
Newsgroups:
comp.lang.c++
Date:
Mon, 29 Sep 2008 20:53:33 -0400
Message-ID:
<2008092920533316807-pete@versatilecodingcom>
On 2008-09-29 20:48:16 -0400, puzzlecracker <ironsel2000@gmail.com> said:

On Sep 29, 6:00 pm, tomas <tomaso...@gmail.com> wrote:

Hi.
I wrote a code similar to this one, for a wrapper application that I
needed:

#include <iostream>

using namespace std;

class Client
{
public:
void setEndpoint(const string& s) throw() { a_endpoint = s;
setEndpoint(); }

protected:
virtual void setEndpoint() throw() = 0;

string a_endpoint;

};

class NotifyClient : public Client
{
public:
const char* endpoint;

private:
void setEndpoint() throw() { endpoint = a_endpoint.c_str(); }

};

int main()
{
NotifyClient client;
string url("http://www.google.com");
client.setEndpoint( url );

return 0;

}

But I'm getting this compile error with g++:

inheritanceTopic.cc:30: error: no matching function for call to
`NotifyClient::setEndpoint(std::string&)'
inheritanceTopic.cc:22: note: candidates are: virtual void
NotifyClient::setEndpoint()

If I change the line,

client.setEndpoint( url );

by

client.Client::setEndpoint( url );

it works.

I'm wondering why is it. I guess it has something to do with function
overloading and the compiler, because if I change names, it works too.

Can anyone give me a better explanation?
I would like to use the same name in the functions, but I don't like
the style of:

client.Client::setEndpoint( url );

pretty ugly....

Thanks in advance,
Tomas.


 void setEndpoint() in the NotifyClient class is private and in the
Client is protected. You cannot lower the access level of the virtual
function. BTW, visa verse would works.


Both work. You're thinking of Java.

The problem is that overloading only takes place among functions
defined in the same scope. Client::setEndpoint(const string&) and
NotifyClient::setEndpoint() are not defined in the same scope, so they
do not overload. The second one hides the first.

--
  Pete
Roundhouse Consulting, Ltd. (www.versatilecoding.com) Author of "The
Standard C++ Library Extensions: a Tutorial and Reference
(www.petebecker.com/tr1book)

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