Class template base

Class template base_dimension

boost::units::base_dimension

Synopsis

template<typename Derived, long N> 
class base_dimension {
public:
  // types
  typedef unspecified dimension_type;  // A convenience typedef. Equivalent to boost::units::derived_dimension<Derived,1>::type. 
  typedef Derived     type;            // Provided for mpl compatability. 
};

Description

Defines a base dimension. To define a dimension you need to provide the derived class (CRTP) and a unique integer.
定義一個基礎量綱。你需要提供派生類(CRTP)和唯一的整數。

 struct my_dimension : boost::units::base_dimension<my_dimension, 1> {};

It is designed so that you will get an error message if you try to use the same value in multiple definitions.
如果你試圖對多個定義使用相同的整數，你會得到一個編譯錯誤。