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
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[SVN r48915]

libs/proto

@@ -1 +1 @@
-Subproject commit 2f3acbfe308661ba6f590b96d199586dce10feb6
+Subproject commit 957f5051026f4a501565d3fc02f3ac4f4747b0e5