# t20019 - Curiously Recurring Template Pattern sequence diagram test case
## Config
```yaml
compilation_database_dir: ..
output_directory: puml
diagrams:
  t20019_sequence:
    type: sequence
    glob:
      - ../../tests/t20019/t20019.cc
    include:
      namespaces:
        - clanguml::t20019
    using_namespace:
      - clanguml::t20019
    start_from:
      - function: "clanguml::t20019::tmain()"
```
## Source code
File t20019.cc
```cpp
#include <cstdio>

namespace clanguml {
namespace t20019 {

// From https://en.cppreference.com/w/cpp/language/crtp

template <class Derived> struct Base {
    void name() { (static_cast<Derived *>(this))->impl(); }
};

struct D1 : public Base<D1> {
    void impl() { std::puts("D1::impl()"); }
};

struct D2 : public Base<D2> {
    void impl() { std::puts("D2::impl()"); }
};

void tmain()
{
    Base<D1> b1;
    b1.name();
    Base<D2> b2;
    b2.name();

    D1 d1;
    d1.name();
    D2 d2;
    d2.name();
}

}
}
```
## Generated UML diagrams
![t20019_sequence](./t20019_sequence.svg "Curiously Recurring Template Pattern sequence diagram test case")