[Boost-users] What's the execution sequence of phoenix::lambda function?

Subject: [Boost-users] What's the execution sequence of phoenix::lambda function?
From: 饭桶 (arthur.wang2_at_[hidden])
Date: 2012-01-15 09:07:02

I'm a newbie for boost phoenix, I wrote a small piece of code but it
totally confuses me about the execution sequence, you can check the code
------------------clip-----------------

std::vector<int> v;
v.push_back(1);
ph::for_each(v,
             ph::lambda[ph::ref(cout)<<"a",
                        ph::ref(cout)<<"b"
                 ])(v);

ph::for_each(arg1,
             ph::lambda[ph::ref(cout)<<"a",
                        ph::for_each(v,
                                         ph::lambda[ph::ref(cout)<<"b",
                                                    ph::ref(cout)<<"c"
                                             ]),
                        ph::ref(cout)<<"d"
                 ])(v);

------------------------clap--------------------------

The first output is "ab" but the second output is "dbca".

It seams ph::for_each is lazy evaluate , but what is the correct one to
make it execute from left to right?

thanks

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