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 the documentation for an old version of Boost. Click here to view this page for the latest version.

Struct distance

boost::proto::functional::distance — A PolymorphicFunctionObject type that invokes the std::distance() function on its arguments.

Synopsis

// In header: <boost/proto/functional/std/iterator.hpp>


struct distance :  proto::callable {
  // member classes/structs/unions
  template<typename This, typename InputIterator> 
  struct result<This(InputIterator, InputIterator)> {
    // types
    typedef typename std::iterator_traits<
      typename boost::remove_const<
        typename boost::remove_reference<InputIterator>::type
      >::type
    >::difference_type type;
  };

  // public member functions
  template<typename InputIterator> 
    void operator()(InputIterator, InputIterator) const;
};

Description

A PolymorphicFunctionObject type that invokes the std::distance() function on its arguments.

`distance` public member functions

template<typename InputIterator> 
  void operator()(InputIterator first, InputIterator last) const;

Returns:

std::distance(first, last)