On 1/3/2010 6:40 AM, David A. Greene wrote:
On Saturday 02 January 2010 11:23:19 David A. Greene wrote:
On Saturday 02 January 2010 05:30:33 Eric Niebler wrote:
There is experimental and undocumented support in Proto for members like else_. See libs/proto/example/virtual_member.cpp for a working example.
Ah, this is what I was looking for. What is the "experimental" and "undocumented" part?
BOOST_PROTO_EXTENDS_MEMBERS
So following this example, I came up with the attached testcase, modified from the one I posted to the development list.
I know the grammar is not strict enough (it should have a separation between "expressions" and "statements") but that's not important.
With the modified testcase display_expr breaks with an incomprehensible compiler error. I assume I'm missing an operator<< definition somewhere but I don't know where it belongs.
That means the tag types you've defined in the keyword namespace are not Streamable. Define a stream insertion operator on keyword::if_. Using display_expr is documented here: http://www.boost.org/doc/libs/1_41_0/doc/html/proto/users_guide.html#boost_p...
And I'm still getting the same compiler error on the #if 0'd code.
Still on my radar ... -- Eric Niebler BoostPro Computing http://www.boostpro.com