Merged revisions 48914 via svnmerge from https://svn.boost.org/svn/boost/trunk
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r48914 | eric_niebler | 2008-09-21 13:48:06 -0700 (Sun, 21 Sep 2008) | 1 line
document as_expr(), as_child(), literal<>, lit() and BOOST_PROTO_EXTENDS() and friends