need help with unfamiliar syntax syntax

[programmy]

so I've been reading SFML blueprints and I've come across
a syntax unfamiliar to me,
I understand that the struct is inheriting something but there's that arrowy
enclosed syntax I dont know about, can anyone shed some light one this?
what is <CompAIWarrior>?
and what is it for/do?

struct CompAIWarrior : Component<CompAIWarrior> <- what is this?
{
explicit CompAIWarrior(int hitPoint,const sf::Time&
timeDelta,int range);
const int _hitPoint;
const sf::Time _delta;
sf::Time _elapsed;
const int _range;
};

[coder777]

what is <CompAIWarrior>?

Actually Component is a template class/struct and CompAIWarrior is the template parameter.
So Component knows how to deal with the CompAIWarrior type. Maybe CompAIWarrior has certain members that Component uses.

[tpb]

This is an interesting pattern. Does anybody know what it's used for?

template <typename T>
struct B {
    // ...
};

struct D : B<D> {   // use derived class itself as template parameter of base
    // ...
};

[mbozzi]

Search for the "Curiously recurring template pattern" or "F-bounded quantification".

See:
http://www.cplusplus.com/forum/general/220370/
http://www.cplusplus.com/forum/general/220967/

[icy1]

Could be used for comparisons with other T's or similarly demonstrating that derived children will have a particular behavior. I imagine the bases of such designs are very short and contain at least one pure method (to enforce said behavior).

#include <iostream>
#include <string>

using namespace std;

template<typename T>
struct Comparable
{
    virtual bool operator< (const T& other) = 0;
};

class Integer : Comparable<Integer> 
{
public:
    Integer(int n, string name) : 
        n_(n), 
        name_(name)
    {        
    }
    
    bool operator< (const Integer& other) override
    {
        return n_ < other.n_;
    }
private:
    int n_;
    string name_;
};

int main()
{
    Integer i(24, "twenty-four");
    Integer j(36, "thirty-six");

    cout << boolalpha;
    cout << "i<j ? " << (i<j) << endl;
    
    return 0;
}

[tpb]

Curiouser and curiouser! Thanks guys.