Re: [boost] [lambda] Can't get simple lambda working...

Subject: Re: [boost] [lambda] Can't get simple lambda working...
From: Robert Dailey (rcdailey_at_[hidden])
Date: 2012-03-19 19:02:54

Seems to be a problem with the std::vector being passed in as const
reference. If I remove the const qualifier it compiles fine.
MessageAttachment::name() is defined as const so it should work; no idea
why const breaks it.

---------
Robert Dailey

On Mon, Mar 19, 2012 at 5:44 PM, Robert Dailey <rcdailey_at_[hidden]> wrote:

> Here is a basic function I have:
>
>
> bool MimeDocument::GetExistingAttachment(
>     std::string const& filename,
>     std::vector<MessageAttachment> const& attachments,
>     MessageAttachment& attachment
> )
> {
>     using namespace boost::lambda;
>     using boost::lambda::_1;
>
>     std::vector<MessageAttachment>::const_iterator it =
>         std::find_if( attachments.begin(), attachments.end(),
>             bind( &MessageAttachment::name, _1 ) == filename
>         );
>
>     if( it != attachments.end() ) {
>         attachment = *it;
>         return true;
>     }
>
>     return false;
> }
>
> MessageAttachment::name() has 2 overloads, one that takes 1 parameter and
> the other that takes no parameter. I'm attempting to call the version that
> accepts no parameters and returns a "char const*". I want to then compare
> this value to the local variable "filename".
>
> This should happen for each object in the vector (_1).
>
> I get various types of compiler errors on MSVC9. They all have to do with
> C2780:
>
> 1>c:\code\work\cmake-mds\server\gmmserver\domino\server\interface\dimime.cpp(287)
> : error C2780: 'const
> boost::lambda::lambda_functor<boost::lambda::lambda_functor_base<boost::lambda::action<10,boost::lambda::function_action<10,T>>,detail::bind_tuple_mapper<const
> Arg1,const Arg2,const Arg3,const Arg4,const Arg5,const Arg6,const
> Arg7,const Arg8,const Arg9,const Arg10>::type>> boost::lambda::bind(const
> Arg1 &,const Arg2 &,const Arg3 &,const Arg4 &,const Arg5 &,const Arg6
> &,const Arg7 &,const Arg8 &,const Arg9 &,const Arg10 &)' : expects 10
> arguments - 2 provided
> 1>
>  c:\code\work\cmake-mds\build-vc9\third_party\boost\1.48.0\include\boost\lambda\detail\bind_functions.hpp(1743)
> : see declaration of 'boost::lambda::bind'
>
> Anyone have any idea what I'm doing wrong?
>
> ---------
> Robert Dailey
>