Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. — Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

This is an older version of Boost and was released in 2024. The current version is 1.89.0.

deref

deref

Description

Returns the type that will be returned by dereferencing an iterator.

Synopsis

template<
    typename I
    >
struct deref
{
    typedef unspecified type;
};

Table 1.12. Parameters

Parameter	Requirement	Description
`I`	Model of Forward Iterator	Operation's argument

Expression Semantics

result_of::deref<I>::type

Return type: Any type

Semantics: Returns the result of dereferencing an iterator of type I.

Header

#include <boost/fusion/iterator/deref.hpp>
#include <boost/fusion/include/deref.hpp>

Example

typedef vector<int,int&> vec;
typedef const vec const_vec;
typedef result_of::begin<vec>::type first;
typedef result_of::next<first>::type second;

typedef result_of::begin<const_vec>::type const_first;
typedef result_of::next<const_first>::type const_second;

BOOST_MPL_ASSERT((boost::is_same<result_of::deref<first>::type, int&>));
BOOST_MPL_ASSERT((boost::is_same<result_of::deref<second>::type, int&>));