Need help with for_each in C++!?

Question

Hello

I want to use for_each in C++

This works without for_each algo.

for (GardenPlan::iterator it = plan.begin(); it != plan.end() ; ++it ){
			(*it)->print(cout);
		}
I've a vector with pointer of shapes. shape has this memberfuction void print(std::ostream &os) const;

I tried this piece of code, but i wont work:
for_each(plan.begin(), plan.end(), bind2nd(mem_fun(&Shape::print ) , os)    );
thanks 4 help

? · Accepted Answer

mem_fun is not compatible with shared_ptr. Since you have TR1, use TR1:

#include <tr1/memory>

#include <tr1/functional>

#include <algorithm>

...

using namespace std::tr1::placeholders;

for_each(plan.begin(), plan.end(),

bind(&Shape::print, _1, std::tr1::ref(os)));

incidentally, if your compiler is new enough, C++0x (in which std::bind2nd has been officially deprecated in favor of std::bind, by the way) can make it more readable with lambdas:

for_each(plan.begin(), plan.end(),

[&os](std::shared_ptr<Shape> p){ p->print(os); });

? · Answer

what exactly is the problem? is bind2nd not called?
also print appears to be __thiscall so it needs a valid class pointer.

Need help with for_each in C++!?

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