Boost C++ Libraries

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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

  // Base class for factory implementation.

  class impl : public attribute::impl {
  };

  class impl_dec : public counter< T >::impl {
  public:
    // construct/copy/destruct
    explicit impl_dec(value_type);

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

  class impl_generic : public counter< T >::impl {
  public:
    // construct/copy/destruct
    impl_generic(value_type, long);

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

  class impl_inc : public counter< T >::impl {
  public:
    // construct/copy/destruct
    explicit impl_inc(value_type);

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

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

Description

This type of attribute acts as a counter, that is, it returns a monotonously changing value each time requested. The attribute value type can be specified as a template parameter. However, the type must be an integral type of size no more than sizeof(long).

`counter` public construct/copy/destruct

```
explicit counter(value_type initial = (value_type) 0, long step = 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 to this amount.

explicit counter(cast_source const & source);

Constructor for casting support