[boost] Re: calling bind with literals

From: David Abrahams (dave_at_[hidden])
Date: 2004-05-07 11:08:30

Douglas Gregor <gregod_at_[hidden]> writes:

> On Friday 07 May 2004 10:30 am, Dill, John wrote:
>> I see your point.  But, what if instead of argument_traits being pass by
>> value, it by default passes by T const&?  What could be done is to have the
>> bind_t arguments be passed by const reference, and then use
>> reference_wrapper to do type-selection to pass by reference.  It still
>> supports literals, and passes by T const& when it can, but everything that
>> is passed by reference must have a ref( object ).  The compiler would fail
>> if you try to pass a reference without a reference_wrapper because it by
>> default tries to pass a T const&.  This wouldn't require the 2^N overloads
>> but would require you to do a ref( object ) for everything passed by
>> reference.  This might also be a workaround for those compilers that don't
>> support T& and T const& overloading.
>
> So we'd be trading lvalue support for literal support. In my experience, 
> lvalues are _much_ more important than literals[*], 

It's literals and rvalues.  Not that I support the proposed trade, but I
should point out that rvalues are important, especially for function
composition.

-- 
Dave Abrahams
Boost Consulting
http://www.boost-consulting.com