[Boost-users] [lambda] Exploring bind syntax.

From: Robert Jones (robertgbjones_at_[hidden])
Date: 2008-07-21 10:46:12

Using the code snippet below as an example,...

#include <vector>
#include <algorithm>
#include <functional>
#include "boost/lambda/lambda.hpp"
#include "boost/lambda/bind.hpp"
#include <boost/function.hpp>

struct S { int methodOfS( ); };

int main( )
{
  typedef std :: vector<S *> Vec;
  using namespace boost :: lambda;

  boost :: function<int( S * )> fn = bind( & S :: methodOfS, _1 );
  Vec v;
  Vec :: iterator match;

  match = find_if( v.begin( ), v.end( ), bind( fn, _1 ) != fn( * v.begin( )
) ); // OK

  match = find_if( v.begin( ), v.end( ), fn( _1 ) != fn( * v.begin( ) ) );
// Fail
}

I find the line marked 'OK' compiles, but not the line marked 'Fail'. Isn't
the
very point of Boost.Bind to enable this kind of syntax? Is there a better
way to write it than my 'Fail' line, but which will still compile?

Thanks, Rob.
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