[boost] [parameter] arg_list.hpp depends on maybe.hpp

Subject: [boost] [parameter] arg_list.hpp depends on maybe.hpp
From: Andrey Semashev (andrey.semashev_at_[hidden])
Date: 2010-05-24 14:10:20

I've been inspecting my code for a possible compilation speedup. The 
code uses Boost.Parameter and thus my attention shifted to it as well.

I noticed that the parameter/aux_/arg_list.hpp header depends on 
parameter/aux_/maybe.hpp, which appears to be quite heavy due to its 
usage of Boost.Optional and other headers. From the code it looks like 
this "maybe" is only related to python binding, and the only thing 
arg_list.hpp needs from it is the maybe_base class, which is trivial.

Is it possible to extract this class to a separate header and remove the 
dependency on maybe.hpp from arg_list.hpp or am I missing something? The 
change looks quite harmless. If I'm not missing anything, am I allowed 
to apply the change?