Re: [Boost-users] [boost][range] fusion::begin and boost::begindontplay nice

From: John Femiani (JOHN.FEMIANI_at_[hidden])
Date: 2007-10-11 13:17:16

> 
> This has, in general, nothing to do with Fusion or Range. The problem
> is, with your two statements,
> 
>  >>>     using namespace boost::fusion;
>  >>>     using namespace boost;
> 
> pulls in a potentially huge number of functions and classes. Many of
> these functions are unconstrained templates, eg. boost::begin() is.
> So which begin() function are you referring to? The correct way to use
> boost.range is to call boost::begin().
> 
> -Thorsten

I was following the examples in the boost range documentation fairly
closely - they do not use boost::begin(). 

Anyhow I would have thought either one of those two should work in this
case.  Why doesn't boost::fusion::begin have a default implementation
that calls boost::begin?

I am really thinking that fusion might not be what I thought it was; I
thought I would be able to take a function that used to work on a
homogeneous container and then I could 'fusion'-ize it so that the same
code would compile with any heterogeneous container or homogenous
container. Apparently this is not the case; I think I need to use Fusion
for heterogeneous and Range for homogenous, and have separate code to
deal with each.

 
-- John