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.

Class template counter

boost::log::attributes::counter — A class of an attribute that counts an integral value.

Synopsis

// In header: <boost/log/attributes/counter.hpp>

template<typename T> 
class counter : public attribute {
public:
  // types
  typedef T value_type;  // A counter value type. 

  // member classes/structs/unions

  // Factory implementation.

  class impl : public attribute::impl {
  public:
    // construct/copy/destruct
    impl(value_type, value_type) noexcept;

    // public member functions
    virtual attribute_value get_value();
  };

  // construct/copy/destruct
  explicit counter(value_type = (value_type) 0, value_type = (value_type) 1);
  explicit counter(cast_source const &);
};

Description

This attribute acts as a counter - it returns a monotonously changing value each time requested. The attribute value type can be specified as a template parameter. The type must be an integral type.

`counter` public construct/copy/destruct

```
explicit counter(value_type initial = (value_type) 0, 
                 value_type step = (value_type) 1);
```
Constructor

Parameters:

initial

Initial value of the counter

step

Changing step of the counter. Each value acquired from the attribute will be greater than the previous one by this amount.

explicit counter(cast_source const & source);

Constructor for casting support