[boost] [preprocessor]undef file iteration include guard?

From: cppljevans_at_[hidden]
Date: 2006-08-29 16:36:20

The test driver in http://boost-consulting.com/vault
/Preprocessor Metaprogramming/ctor_template.zip
only works if the ctor_template.hpp file #undef's
the include guard as follows:

#undef boost_forwarder_ctor_template_included

However, this need is not mentioned in:
http://www.boost.org/libs/preprocessor/doc/topics/file_iteration.html

Maybe it should be mentioned there or am I missing
something?