Re: how to use a static member function in find_if
puzzlecracker <ironsel2000@gmail.com> wrote:
"Daniel T." <danie...@earthlink.net> wrote:
"want.to.be.professer" <guolihui...@gmail.com> wrote:
#include <iostream>
#include <list>
#include <algorithm>
#include <functional>
using namespace std;
class T
{
public:
? ? static bool IsEqual( int n, int m )
? ? {
? ? ? ? return m ==n;
? ? }
? ? static void print ( int n )
? ? {
? ? ? ? std::cout << " ? " << n << std::endl;
? ? }
};
int main()
{
? ? T cT;
? ? int a[10] = {12, 12,23,35, 23,12, 12,23,35, 23};
? ? int* q = std::find_if(a, a + 10, std::bind1st( (&T::IsEqual),
35 ) ); ? ?// Error!!!!!!!!!!!!!!!!!!!!!!!!!
int* q = find_if( a, a + 10, bind1st( ptr_fun( &T::IsEqual ) ), 35 );
http://www.sgi.com/tech/stl/ptr_fun.html
? ? for_each( a, a + 10,
&T::print ); ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? // Work
Fine
? ? //std::cout << "-------" << *q << std::endl;
? ? return 0;
}
But How can I use IsEqual function?
why do you need ptr_fun here?
Because, bind1st requires an AdaptableBinaryFunction for its parameter,
which &T::IsEqual is not (no function is.)
Before you ask, an AdaptableBinaryFunction has typedefs for its
first_argument_type, second_argument_type and result_type.
http://www.sgi.com/tech/stl/AdaptableBinaryFunction.html
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