[Boost-users] using bind with find_if

9 Mar 2011

      Hello,

I am currently using find_if with bind2nd to perform a search on a vector. 
My current code looks like this:

struct OverrideMatches : public std::binary_function<const TItemOverride, 
const TItemOverride, bool>
{
   bool operator()( const TItemOverride& OverrideSource, TItemOverride 
OverrideTarget ) const
   {
      return OverrideSource.ChildAssyItemRecNo == 
OverrideTarget.ChildAssyItemRecNo &&
             OverrideSource.LinkItemRecNo == OverrideTarget.LinkItemRecNo;
   }
};

TItemOverrideGateway::Container_t::iterator where =
  std::find_if( FOverridesContainer.begin(),
                FOverridesContainer.end(),
                std::bind2nd( OverrideMatches(),
                TItemOverride( "", 0, "", 0, ChildItemRecNo, 
LinkItemRecNo ) ) );

I would like to eliminate the need for that temporary object to hold the 
values I am searching for (and just specify the values instead), and to do 
that, I want to try using boost::bind instead of std::bind2nd, but I have 
not been able to determing exactly what that syntax would look like.  I know 
I will need placeholders for the values to search on (ChildItemRecNo, 
LinkItemRecNo), but then how does the element from the vector get passed to 
the

I think I want the functor to look something like this:

struct OverrideMatches
{
    bool operator()( const TItemOverride &OverrideSource,
                              const RecNo_t ChildItemRecNo,
                              const RecNo_t LinkItemRecNo )
    {
        return OverrideSource.ChildAssyItemRecNo == ChildItemRecNo &&
                  OverrideSource.LinkItemRecNo == LinkItemRecNo;
    }
};

If the above functor is correct (and maybe it's not, in which case, please 
correct me), how do I then rewrite std::find_if to use it with boost::bind?

Thank you very much,

Dennis Jones