about bind2nd

[benben]

I tried to do the following:

bind2nd(ptr_fun(&tolower<char>), locale());

But was hit with errors claiming some where deep down the STL library
some code is trying to take a reference to a reference type.

I guess that is because the std::tolower<>() template takes a reference
to a locale as its second parameter then bind2nd tries to take the
reference of that parameter. But how to I circumvent this?

Regards,
Ben

 

[Kai-Uwe Bux]

I tried to do the following:

bind2nd(ptr_fun(&tolower<char>), locale());

But was hit with errors claiming some where deep down the STL library
some code is trying to take a reference to a reference type.

I guess that is because the std::tolower<>() template takes a reference
to a locale as its second parameter then bind2nd tries to take the
reference of that parameter. But how to I circumvent this?

One way is to use boost::bind.

#include <locale>
#include <iostream>
#include <boost/bind.hpp>
#include <iterator>
#include <algorithm>

int main ( void ) {
std::string str = "HELLO WORLD!";
std::transform
( str.begin(), str.end(),
std:stream_iterator<char>( std::cout ),
boost::bind( &std::tolower<char>, _1, std::locale() ) );
std::cout << '\n';
}


Best

Kai-Uwe Bux

 

[Pete Becker]

One way is to use boost::bind.

Another way is to use std::tr1::bind. <g>

--

-- Pete

Author of "The Standard C++ Library Extensions: a Tutorial and
Reference." For more information about this book, see
www.petebecker.com/tr1book.