使用的for_each和boost ::绑定指针的向量 [英] Using for_each and boost::bind with a vector of pointers

问题描述

我有指针的载体。我想呼吁每个元素的功能，但该功能需要一个参考。有没有一种简单的方法来解引用的元素？

I have a vector of pointers. I would like to call a function for every element, but that function takes a reference. Is there a simple way to dereference the elements?

例如：

MyClass::ReferenceFn( Element & e ) { ... }

MyClass::PointerFn( Element * e ) { ... }

MyClass::Function()
{
    std::vector< Element * > elements;
    // add some elements...

    // This works, as the argument is a pointer type
    std::for_each( elements.begin(), elements.end(),
                   boost::bind( &MyClass::PointerFn, boost::ref(*this), _1 ) );

    // This fails (compiler error), as the argument is a reference type
    std::for_each( elements.begin(), elements.end(),
                   boost::bind( &MyClass::ReferenceFn, boost::ref(*this), _1 ) );
}

我可以创建一个肮脏的小包装，需要一个指针，但我想必须有一个更好的办法？

I could create a dirty little wrapper that takes a pointer, but I figured there had to be a better way?

推荐答案

您可以使用的boost :: indirect_iterator ：

std::for_each( boost::make_indirect_iterator(elements.begin()), 
               boost::make_indirect_iterator(elements.end()),
               boost::bind( &MyClass::ReferenceFn, boost::ref(*this), _1 ) );

这将间接引用其运算符*两次改编的迭代器。

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