On Feb 4, 2008 9:05 PM, Alexis H. Rivera-Rios <
ahrivera@yahoo.com> wrote:
Hi,
I'm trying to use a transform iterator and lower_bound
to search a list of integers as if it was list of
booleans.
According to the message the const_mem_fun_ref_t
doesn't have a default constructor. Is there a way to
make this code compile?
Your help will be appreciated!
Alex
#include<functional>
#include <vector>
#include <algorithm>
#include <boost/iterator/transform_iterator.hpp>
class T
{
public:
int _a;
T(int a) : _a(a) {}
bool greaterZero() const { return _a > 0; }
};
int main(void)
{
typedef std::vector<T> Tlist;
typedef std::const_mem_fun_ref_t<bool,T> Function;
typedef boost::transform_iterator<Function,
Tlist::const_iterator> Iterator;
Tlist x;
Iterator
b(x.begin(),std::mem_fun_ref<bool,T>(&T::greaterZero)),
e(x.end(),std::mem_fun_ref<bool,T>(&T::greaterZero));
std::lower_bound(b,e,false);
}
Error log:
BD Software STL Message Decryptor v3.10 for gcc 2/3/4
matob.cpp:28:2: warning: no newline at end of file
/cygdrive/c/opt/boost_1_34_1/boost/iterator/transform_iterator.hpp:
In
constructor
`boost::transform_iterator<
main()::Function, vector<T>::const_iterator,
boost::use_default
, boost::use_default
>::transform_iterator()':
stl_algo.h:2627: instantiated from
`boost::transform_iterator<
main()::Function, vector<T>::const_iterator,
boost::use_default
, boost::use_default
> lower_bound(
boost::transform_iterator<
main()::Function,
vector<T>::const_iterator, boost::use_default
, boost::use_default
>, boost::transform_iterator<
main()::Function,
vector<T>::const_iterator, boost::use_default
, boost::use_default
>, const bool &
)'
matob.cpp:26: instantiated from here
/cygdrive/c/opt/boost_1_34_1/boost/iterator/transform_iterator.hpp:100:
error:
No match for `const_mem_fun_ref_t<bool,
T>::const_mem_fun_ref_t()'
stl_function.h:640: candidates are:
const_mem_fun_ref_t<bool, T>
::const_mem_fun_ref_t(const
const_mem_fun_ref_t<bool, T> &)
stl_function.h:644: const_mem_fun_ref_t<
bool, T>::const_mem_fun_ref_t(bool (T::*)()
const)
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