A helper class to define CRTP class hierarchies. More...

#include <crtp.hpp>

Inheritance diagram for m::crtp< ConcreteType, CRTPBaseType, TParams >:

Collaboration diagram for m::crtp< ConcreteType, CRTPBaseType, TParams >:

Public Types
using	actual_type = ConcreteType

Public Member Functions
actual_type &	actual ()

const actual_type &	actual () const

Private Member Functions
	crtp ()

Private Attributes
friend	CRTPBaseType< actual_type, TParams... >

Detailed Description

template<typename ConcreteType, template< typename... > typename CRTPBaseType, typename... TParams>
struct m::crtp< ConcreteType, CRTPBaseType, TParams >

A helper class to define CRTP class hierarchies.

Taken from An Implementation Helper For The Curiously Recurring Template Pattern - Fluent C++.

This CRTP helper ensures that the

Template Parameters

ConcreteType	actually inherits from
CRTPBaseType.	The helper defines a method `actual()` that allows for safely casting the CRTP base type
CRTPBaseType	to the
ConcreteType,properly	`const`-quanified.

A class that wants to make use of CRTP should inherit from this helper. The following example demonstrates this:

template<typename ConcreteType>
struct CRTPBase : crtp<ConcreteType, CRTPBase>
{
    using crtp<ConcreteType, CRTPBase>::actual;
};

It is also possible for the class implementing CRTP to take additional template parameters:

template<typename ConcreteType, typename T1, typename T2>
struct CRTPBase : crtp<ConcreteType, CRTPBase, T1, T2>
{
    using crtp<ConcreteType, CRTPBase, T1, T2>::actual;
};

This should also work with variadic templates:

template<typename ConcreteType, typename... Args>
struct CRTPBase : crtp<ConcreteType, CRTPBase, Args...>
{
    using crtp<ConcreteType, CRTPBase, Args...>::actual;
};

Definition at line 49 of file crtp.hpp.