Re: [Boost-users] [graph][spirit][variant] Boost.Graph and Boost.Spirit incompatible ?

Subject: Re: [Boost-users] [graph][spirit][variant] Boost.Graph and Boost.Spirit incompatible ?
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2010-03-04 15:49:49

AMDG

Jeremiah Willcock wrote:
> There are a lot of BGL overloads of get; it is intended to be found by 
> ADL, and there's (at least) one definition for each graph type.  The 
> graph library's get has been around for a while.  It is not globally 
> reserved, at least not technically; it only applies to known graph and 
> property map types, just like variant's.  The problem is that 
> variant's get takes explicit template arguments and that seems to make 
> the overloading work incorrectly.  I suspect that the error in this 
> thread, for example, is coming from the boost::get version for 
> two_bit_color_map; that function is restricted to work on only that 
> property map type but instantiating its signature appears to be 
> failing without SFINAE because of the explicit template argument.

SFINAE doesn't apply for this overload of get.

> I think this is something that's fixed in C++0x but that doesn't help 
> us now.  Your workaround might fix the common cases though (since the 
> compiler seems to differentiate functions based on the number of 
> template arguments given); for some reason, the extra template 
> argument in ::key_type is important in that definition of get.  It 
> will be annoying to have to work around this issue repeatedly, though.

Property maps that use put_get_helper seem to be okay.

In Christ,
Steven Watanabe